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1.  Behavioral Self-Regulation and Weight-Related Behaviors in Inner-City Adolescents: A Model of Direct and Indirect Effects 
Childhood obesity (Print)  2011;7(4):306-315.
This study examined the association of two distinct self-regulation constructs, effortful control and dysregulation, with weight-related behaviors in adolescents and tested whether these effects were mediated by self-efficacy variables.
A school-based survey was conducted with 1771 adolescents from 11 public schools in the Bronx, New York. Self-regulation was assessed by multiple indicators and defined as two latent constructs. Dependent variables included fruit/vegetable intake, intake of snack/junk food, frequency of physical activity, and time spent in sedentary behaviors. Structural equation modeling examined the relation of effortful control and dysregulation to lifestyle behaviors, with self-efficacy variables as possible mediators.
Study results showed that effortful control had a positive indirect effect on fruit and vegetable intake, mediated by self-efficacy, as well as a direct effect. Effortful control also had a positive indirect effect on physical activity, mediated by self-efficacy. Dysregulation had direct effects on intake of junk food/snacks and time spent in sedentary behaviors.
These findings indicate that self-regulation characteristics are related to diet and physical activity and that some of these effects are mediated by self-efficacy. Different effects were noted for the two domains of self-regulation. Prevention researchers should consider including self-regulation processes in programs to improve health behaviors in adolescents.
PMCID: PMC3522174  PMID: 23243551
2.  Diet, Psychosocial Factors Related to Diet and Exercise, and Cardiometabolic Conditions in Southern Californian Native Hawaiians 
Hawaii Medical Journal  2010;69(5 suppl 2):16-20.
Native Hawaiians are at higher risk for cardiometabolic disease, including diabetes and cardiovascular disease compared with other ethnic groups. Diet, body mass index (BMI) and psychosocial, as well as cultural issues may influence risk for cardiometabolic disease. Our team conducted a community-based participatory research study and examined diet, height/weight, psychosocial factors, and community health concerns in Native Hawaiians living in Southern California.
Design and Methods
Cross-section of 55 participants, ≥ 18 years old. Dietary data were collected via three 24-hr dietary recalls, anthropometrics were measured, and psychosocial factors and cardiometabolic conditions were self-reported. Talk story related to diet and health was completed in a sub-sample. Means and frequencies were calculated on dietary intakes, cardiometabolic disease and BMI. Independent t-test and chi square analyses, as appropriate, were performed to assess differences in dietary intakes, obesity and psychosocial factors between those with and without a pre-existing cardiometabolic condition.
Of those with pre-existing health conditions (n = 28), 72% reported being diagnosed with a cardiometabolic condition. For those with pre-existing cardiometabolic conditions, the daily vegetable consumption was 2.57 servings (± 1.66) and the mean fruit consumption was 1.43 servings (± 0.1.99). The mean fiber intake was 16.24 grams (± 6.92), the mean percentage energy from fat was 34.82% (± 6.40) and the mean % energy from carbohydrate was 47.15 (± 6.77). The psychosocial data showed significantly (p ≤ 0.05) lower social support, social interaction, self-monitoring and cognitive-behavioral strategies related to exercise for those with cardiometabolic disease compared with those without disease. All the talk story discussion groups expressed concern over diabetes and weight management, both as an individual and community issue.
The dietary data indicate that Native Hawaiians residing in Southern California should aim to increase their vegetable, fiber, and reduce % energy from fat and saturated fat. Additionally, the psychosocial data suggests that implementing physical activity programs based on socio-cultural values such as ohana, community gatherings, as well as individual self-monitoring and cognitive-behavioral strategies may improve cardiometabolic outcomes. In efforts to reduce cardiometabolic disease disparity, these data suggest that Native Hawaiians in Southern California are aware and concerned about cardiometabolic disease in the community, and that implementation of an effective energetic (diet plus physical activity) intervention that is socially, and culturally specific for Native Hawaiians in Southern California is critical.
PMCID: PMC3158438  PMID: 20544604
3.  New Moves—Preventing Weight-Related Problems in Adolescent Girls 
Weight-related problems are prevalent in adolescent girls.
To evaluate New Moves, a school-based program aimed at preventing weight-related problems in adolescent girls.
School-based group-randomized controlled design.
356 girls (mean age=15.8± 1.2 years) from six intervention and six control high schools. Over 75% of the girls were racial/ethnic minorities and 46% were overweight or obese. Data were collected in 2007–2009 and analyzed in 2009–2010.
An all-girls physical education class, supplemented with nutrition and self-empowerment components, individual sessions using motivational interviewing, lunch meetings, and parent outreach.
Main outcome measures
Percent body fat, BMI, physical activity, sedentary activity, dietary intake, eating patterns, unhealthy weight control behaviors, and body/self-image.
New Moves did not lead to significant changes in the girls’ percent body fat or BMI but improvements were seen for sedentary activity, eating patterns, unhealthy weight control behaviors, and body/self-image. For example, in comparison to control girls, at 9-month follow-up, intervention girls decreased their sedentary behaviors by approximately one 30-minute block a day (p=.050); girls increased their portion control behaviors (p=.014); the percentage of girls using unhealthy weight control behaviors decreased by 13.7% (p=.021), and improvements were seen in body image (p=.045) and self-worth (p=.031). Additionally, intervention girls reported more support by friends, teachers, and families for healthy eating and physical activity.
New Moves provides a model for addressing the broad spectrum of weight-related problems among adolescent girls. Further work is needed to enhance the effectiveness of interventions to improve weight status of youth.
PMCID: PMC2978965  PMID: 20965379
4.  Tailored, iterative, printed dietary feedback is as effective as group education in improving dietary behaviours: results from a randomised control trial in middle-aged adults with cardiovascular risk factors 
Tailored nutrition interventions have been shown to be more effective than non-tailored materials in changing dietary behaviours, particularly fat intake and fruit and vegetable intake. But further research examining efficacy of tailored nutrition education in comparison to other nutrition education methods and across a wider range of dietary behaviours is needed. The Stages to Healthy Eating Patterns Study (STEPs) was an intervention study, in middle-aged adults with cardiovascular risk factors, to examine the effectiveness of printed, tailored, iterative dietary feedback delivered by mail in improving short-term dietary behaviour in the areas of saturated fat, fruit, vegetable and grain and cereal intake.
STEPs was a 3-month randomised controlled trial with a pre and post-test design. There were three experimental conditions: 1) tailored, iterative, printed dietary feedback (TF) with three instalments mail-delivered over a 3-month period that were re-tailored to most recent assessment of dietary intake, intention to change and assessment of self-adequacy of dietary intake. Tailoring for dietary intake was performed on data from a validated 63-item combination FFQ designed for the purpose 2) small group nutrition education sessions (GE): consisting of two 90-minute dietitian-led small group nutrition education sessions and 3) and a wait-listed control (C) group who completed the dietary measures and socio-demographic questionnaires at baseline and 3-months later. Dietary outcome measures in the areas of saturated fat intake (g), and the intake of fruit (serves), vegetables (serves), grain and cereals as total and wholegrain (serves) were collected using 7-day estimated dietary records. Descriptive statistics, paired t-tests and general linear models adjusted for baseline dietary intake, age and gender were used to examine the effectiveness of different nutrition interventions.
The TF group reported a significantly greater increase in fruit intake (0.3 serves/d P = 0.031) in comparison to GE and the C group. All three intervention groups showed a reduction in total saturated fat intake. GE also had a within-group increase in mean vegetable intake after 3 months, but this increase was not different from changes in the other groups.
In this study, printed, tailored, iterative dietary feedback was more effective than small group nutrition education in improving the short-term fruit intake behaviour, and as effective in improving saturated fat intake of middle-aged adults with cardiovascular risk factors. This showed that a low-level dietary intervention could achieve modest dietary behaviour changes that are of public health significance.
PMCID: PMC3117757  PMID: 21595978
5.  Diet and Physical Activity for the Prevention of Noncommunicable Diseases in Low- and Middle-Income Countries: A Systematic Policy Review 
PLoS Medicine  2013;10(6):e1001465.
Carl Lachat and colleagues evaluate policies in low- and middle-income countries addressing salt and fat consumption, fruit and vegetable intake, and physical activity, key risk factors for non-communicable diseases.
Please see later in the article for the Editors' Summary
Diet-related noncommunicable diseases (NCDs) are increasing rapidly in low- and middle-income countries (LMICs) and constitute a leading cause of mortality. Although a call for global action has been resonating for years, the progress in national policy development in LMICs has not been assessed. This review of strategies to prevent NCDs in LMICs provides a benchmark against which policy response can be tracked over time.
Methods and Findings
We reviewed how government policies in LMICs outline actions that address salt consumption, fat consumption, fruit and vegetable intake, or physical activity. A structured content analysis of national nutrition, NCDs, and health policies published between 1 January 2004 and 1 January 2013 by 140 LMIC members of the World Health Organization (WHO) was carried out. We assessed availability of policies in 83% (116/140) of the countries. NCD strategies were found in 47% (54/116) of LMICs reviewed, but only a minority proposed actions to promote healthier diets and physical activity. The coverage of policies that specifically targeted at least one of the risk factors reviewed was lower in Africa, Europe, the Americas, and the Eastern Mediterranean compared to the other two World Health Organization regions, South-East Asia and Western Pacific. Of the countries reviewed, only 12% (14/116) proposed a policy that addressed all four risk factors, and 25% (29/116) addressed only one of the risk factors reviewed. Strategies targeting the private sector were less frequently encountered than strategies targeting the general public or policy makers.
This review indicates the disconnection between the burden of NCDs and national policy responses in LMICs. Policy makers urgently need to develop comprehensive and multi-stakeholder policies to improve dietary quality and physical activity.
Please see later in the article for the Editors' Summary
Editors' Summary
Noncommunicable diseases (NCDs)—chronic medical conditions including cardiovascular diseases (heart disease and stroke), diabetes, cancer, and chronic respiratory diseases (chronic obstructive pulmonary disease and asthma)—are responsible for two-thirds of the world's deaths. Nearly 80% of NCD deaths, close to 30 million per year, occur in low- and middle-income countries (LMICs), where they are also rising most rapidly. Diet and lifestyle (including smoking, lack of exercise, and harmful alcohol consumption) influence a person's risk of developing an NCD and of dying from it. Because they can be modified, these risk factors have been at the center of strategies to combat NCDs. In 2004, the World Health Organization (WHO) adopted the Global Strategy on Diet, Physical Activity and Health. For diet, it recommended that individuals achieve energy balance and a healthy weight; limit energy intake from total fats and shift fat consumption away from saturated fats to unsaturated fats and towards the elimination of trans-fatty acids; increase consumption of fruits, vegetables, legumes, whole grains, and nuts; limit the intake of free sugars; and limit salt consumption from all sources and ensure that salt is iodized. For physical activity, it recommended at least 30 minutes of regular, moderate-intensity physical activity on most days throughout a person's life.
Why Was This Study Done?
By signing onto the Global Strategy in 2004, WHO member countries agreed to implement it with high priority. A first step of implementation is usually the development of local policies. Consequently, one of the four objectives of the WHO Global Strategy is “to encourage the development, strengthening and implementation of global, regional, national and community policies and action plans to improve diets and increase physical activity.” Along the same lines, in 2011 the United Nations held a high-level meeting in which the need to accelerate the policy response to the NCD epidemic was emphasized. This study was done to assess the existing national policies on NCD prevention in LMICs. Specifically, the researchers examined how well those policies matched the WHO recommendations for intake of salt, fat, and fruits and vegetables, as well as the recommendations for physical activity.
What Did the Researchers Do and Find?
The researchers searched the Internet (including websites of relevant ministries and departments) for all publicly available national policies related to diet, nutrition, NCDs, and health from all 140 WHO member countries classified as LMICs by the World Bank in 2011. For countries for which the search did not turn up policies, the researchers sent e-mail requests to the relevant national authorities, to the regional WHO offices, and to personal contacts. All documents dated from 1 January 2004 to 1 January 2013 that included national objectives and guidelines for action regarding diet, physical exercise, NCD prevention, or a combination of the three, were analyzed in detail.
Most of the policies obtained were not easy to find and access. For 24 countries, particularly in the Eastern Mediterranean, the researchers eventually gave up, unable to establish whether relevant national policies existed. Of the remaining 116 countries, 29 countries had no relevant policies, and another 30 had policies that failed to mention specifically any of the diet-related risk factors included in the analysis. Fifty-four of the 116 countries had NCD policies that addressed at least one of the risk factors. Thirty-six national policy documents contained strategies to increase fruit and vegetable intake, 20 addressed dietary fat consumption, 23 aimed to limit salt intake, and 35 had specific actions to promote physical activity. Only 14 countries, including Jamaica, the Philippines, Iran, and Mongolia, had policies that addressed all four risk factors. The policies of 27 countries mentioned only one of the four risk factors.
Policies primarily targeted consumers and government agencies and failed to address the roles of the business community or civil society. Consistent with this, most were missing plans, mechanisms, and incentives to drive collaborations between the different stakeholders.
What Do These Findings Mean?
More than eight years after the WHO Global Strategy was agreed upon, only a minority of the LMICs included in this analysis have comprehensive policies in place. Developing policies and making them widely accessible is a likely early step toward specific implementation and actions to prevent NCDs. These results therefore suggest that not enough emphasis is placed on NCD prevention in these countries through actions that have been proven to reduce known risk factors. That said, the more important question is what countries are actually doing to combat NCDs, something not directly addressed by this analysis.
In richer countries, NCDs have for decades been the leading cause of sickness and death, and the fact that public health strategies need to emphasize NCD prevention is now widely recognized. LMICs not only have more limited resources, they also continue to carry a large burden from infectious diseases. It is therefore not surprising that shifting resources towards NCD prevention is a difficult process, even if the human cost of these diseases is massive and increasing. That only about 3% of global health aid is aimed at NCD prevention does not help the situation.
The authors argue that one step toward improving the situation is better sharing of best practices and what works and what doesn't in policy development. They suggest that an open-access repository like one that exists for Europe could improve the situation. They offer to organize, host, and curate such a resource under the auspices of WHO, starting with the policies retrieved for this study, and they invite submission of additional policies and updates.
Additional Information
Please access these websites via the online version of this summary at
This study is further discussed in a PLOS Medicine Perspective by Stuckler and Basu
The WHO website on diet and physical activity contains links to various documents, including a diet and physical activity implementation toolbox that contains links to the 2004 Global Strategy document and a Framework to Monitor and Evaluate Implementation
There is a 2011 WHO primer on NCDs entitled Prioritizing a Preventable Epidemic
A recent PLOS Medicine editorial and call for papers addressing the global disparities in the burden from NCDs
A PLOS Blogs post entitled Politics and Global HealthAre We Missing the Obvious? and associated comments discuss the state of the fight against NCDs in early 2013
The NCD Alliance was founded by the Union for International Cancer Control, the International Diabetes Federation, the World Heart Federation, and the International Union Against Tuberculosis and Lung Disease; its mission is to combat the NCD epidemic by putting health at the center of all policies
The WHO European Database on Nutrition, Obesity and Physical Activity (NOPA) contains national and subnational surveillance data, policy documents, actions to implement policy, and examples of good practice in programs and interventions for the WHO European member states
PMCID: PMC3679005  PMID: 23776415
6.  The effects of a controlled worksite environmental intervention on determinants of dietary behavior and self-reported fruit, vegetable and fat intake 
BMC Public Health  2006;6:253.
Eating patterns in Western industrialized countries are characterized by a high energy intake and an overconsumption of (saturated) fat, cholesterol, sugar and salt. Many chronic diseases are associated with unhealthy eating patterns. On the other hand, a healthy diet (low saturated fat intake and high fruit and vegetable intake) has been found important in the prevention of health problems, such as cancer and cardio-vascular disease (CVD). The worksite seems an ideal intervention setting to influence dietary behavior. The purpose of this study is to present the effects of a worksite environmental intervention on fruit, vegetable and fat intake and determinants of behavior.
A controlled trial that included two different governmental companies (n = 515): one intervention and one control company. Outcome measurements (short-fat list and fruit and vegetable questionnaire) took place at baseline and 3 and 12 months after baseline. The relatively modest environmental intervention consisted of product information to facilitate healthier food choices (i.e., the caloric (kcal) value of foods in groups of products was translated into the number of minutes to perform a certain (occupational) activity to burn these calories).
Significant changes in psychosocial determinants of dietary behavior were found; subjects at the intervention worksite perceived more social support from their colleagues in eating less fat. But also counter intuitive effects were found: at 12 months the attitude and self-efficacy towards eating less fat became less positive in the intervention group. No effects were found on self-reported fat, fruit and vegetable intake.
This environmental intervention was modestly effective in changing behavioral determinant towards eating less fat (social support, self-efficacy and attitude), but ineffective in positively changing actual fat, fruit and vegetable intake of office workers.
PMCID: PMC1626462  PMID: 17044935
7.  Covariation of Adolescent Physical Activity and Dietary Behaviors over 12-Months 
This study examined covariation among changes in dietary, physical activity, and sedentary behaviors over 12 months among adolescents participating in a health behavior intervention. Evidence of covariation among behaviors would suggest multi-behavior interventions could have synergistic effects.
Prospective analyses were conducted with baseline and 12 month assessments from a randomized controlled trial to promote improved diet, physical activity and sedentary behaviors (experimental condition) or SUN protection behaviors (comparison condition). Participants were adolescent girls and boys (N = 878) aged 11 to 15 years on entry. The main outcomes were: diet, based on multiple 24-hour recalls (total fat, grams of fiber, servings of fruit and vegetables, total calories); average daily energy expenditure (kcals/kg) based on 7-Day physical activity recall interviews; daily minutes of moderate-vigorous physical activity minutes from accelerometery; and self-reported daily hours of sedentary behavior.
Covariation was found between fat and calories (r = .16), fiber and calories (r = .53), fiber and fruit/vegetables (r = .53), calories and fruit/vegetables (r = .34), and fruit and vegetables and sedentary behavior (r = -.12) for the total sample (all p < .01). The pattern of findings was similar for most subgroups defined by sex and study condition.
The strongest covariation was observed for diet variables that are inherently related (calories and fat, fiber, and fruit/vegetables). Little covariation was detected within or between other diet, physical activity and sedentary behavior domains suggesting that interventions to improve these behaviors in adolescents need to include specific program components for each target behavior of interest.
PMCID: PMC2121661  PMID: 17950167
8.  Self-Reported Dietary Intake Following Endurance, Resistance and Concurrent Endurance and Resistance Training 
With regards to obesity-related disease the impact of exercise training on health depends on the ability of exercise to promote a negative energy balance. Exercise's effect on promoting a negative energy balance is more likely to occur if exercise can induce a favourable dietary intake such as a reduced relative fat content in the diet. As such, the aim of this study was to evaluate and compare the effectiveness of aerobic training, weight training and concurrent aerobic and weight training on self-reported dietary intake. The effects of 16 weeks of aerobic (n = 12), weight (n = 13) and concurrent aerobic and weight training (n = 13) on self-reported dietary intakes were compared in previously sedentary males using the computer-based Dietary Manager® software programme. Only the concurrent aerobic and weight training group showed significant (p ≤ 0.05) reductions in total kilocalories, carbohydrates, proteins and fats consumed while the aerobic training group showed significant reductions in fat intake at the completion of the experimental period (before: 91.0 ± 42.1g versus after: 77.1 ± 62.1g). However, no changes were observed in self-reported dietary intake in the weight training or non-exercising control groups. It is concluded that concurrent aerobic and weight training is the most effective mode of exercise at promoting a favourable improvement in self-reported dietary intake in the short term. This finding provides support for efforts to promote increases in overall physical activity in an attempt to modify the patterns of dietary intake.
Key pointsConcurrent aerobic and weight training can significantly reduce the amount of total kilocalories, carbohydrates, proteins and fats consumed.Aerobic training can significantly reduce fat intake.Weight training resulted in no changes in dietary intake.Concurrent aerobic and weight training is the most effective mode of exercise at promoting a favourable improvement in self-reported dietary intake.
PMCID: PMC3761454  PMID: 24149458
Kilocalories; carbohydrate; diet; exercise; fat; protein
9.  The association of emotion regulation with lifestyle behaviors in inner-city adolescents 
Eating behaviors  2013;14(4):10.1016/j.eatbeh.2013.07.009.
Recent research suggests a role of cognitive self-regulation skills on obesity and lifestyle behaviors. However, very little is known about the role of emotion regulation. This study examined the association of emotion regulation with lifestyle behaviors and examined a mediational model testing effects of emotion regulation through self-efficacy and depressive symptoms.
A cross-sectional study was conducted with 602 adolescents (mean age 12.7 years) from 4 public schools in the Bronx, NY. The sample was 58% female, predominantly Hispanic (74%) and US born (81%). Emotion regulation was assessed by 3 indicators and defined as a latent variable. Dependent variables included fruit/vegetable intake, snack/junk food intake, frequency of physical activity, and time spent in sedentary behaviors. Structural equation modeling examined the association of emotion regulation with lifestyle behaviors, with self-efficacy and depressive symptoms defined as potential mediators.
The analyses showed that there was a positive association of emotion regulation with higher intake of fruits/vegetable and greater physical activity, which was mediated by self-efficacy. Emotion regulation was related to snack/junk food intake and sedentary behavior, and the structural equation model indicated pathways through an inverse relation to depressive symptoms, but these pathways were only observed in adolescent girls and not boys.
These findings indicate that the ability to regulate emotions among adolescents has a role in weight-related behaviors. Future studies may need to explore the relation of other dimensions of emotion to positive health behaviors and study aspects of emotion regulation that may be more relevant for boys.
PMCID: PMC3817414  PMID: 24183148
Adolescents; Lifestyle behaviors; Emotion regulation; Depressive Symptoms; Self-efficacy
10.  Web-Based Guide to Health: Relationship of Theoretical Variables to Change in Physical Activity, Nutrition and Weight at 16-Months 
Evaluation of online health interventions should investigate the function of theoretical mechanisms of behavior change in this new milieu.
To expand our understanding of how Web-based interventions influence behavior, we examined how changes at 6 months in participants’ psychosocial characteristics contributed to improvements at 16 months in nutrition, physical activity (PA), and weight management as a result of the online, social cognitive theory (SCT)-based Guide to Health intervention (WB-GTH).
We conducted recruitment, enrollment, and assessments online with 272 of 655 (41.5%) participants enrolling in WB-GTH who also completed 6- and 16-month follow-up assessments. Participants’ mean age was 43.68 years, 86% were female, 92% were white, mean education was 17.45 years, median income was US $85,000, 84% were overweight or obese, and 73% were inactive. Participants received one of two equally effective versions of WB-GTH. Structural equation analysis of theoretical models evaluated whether psychosocial constructs targeted by WB-GTH contributed to observed health behavior changes.
The longitudinal model provided good fit to the data (root mean square error of approximation <.05). Participants’ weight loss at 16 months was predicted by improvements in their PA (betatotal = -.34, P = .01), consumption of fruits and vegetables (F&V) (betatotal = -.20, P = .03) and calorie intake (betatotal = .15, P = .04). Improvements at 6 months in PA self-efficacy (betatotal = -.10, P = .03), PA self-regulation (betatotal = -.15, P = .01), nutrition social support (betatotal = -.08, P = .03), and nutrition outcome expectations (betatotal = .08, P = .03) also contributed to weight loss. WB-GTH users with increased social support (betatotal = .26, P = .04), self-efficacy (betatotal = .30, P = .01), and self-regulation (betatotal = .45, P = .004) also exhibited improved PA levels. Decreased fat and sugar consumption followed improved social support (betatotal = -.10, P = .02), outcome expectations (betatotal = .15, P = .007), and self-regulation (betatotal = -.14, P = .008). Decreased calorie intake followed increased social support (betatotal = -.30, P < .001). Increased F&V intake followed improved self-efficacy (betatotal = .20, P = .01), outcome expectations (betatotal = -.29, P = .002), and self-regulation (betatotal = .27, P = .009). Theorized indirect effects within SCT variables were also supported.
The WB-GTH influenced behavior and weight loss in a manner largely consistent with SCT. Improving social support, self-efficacy, outcome expectations, and self-regulation, in varying combinations, led to healthier diet and exercise habits and concomitant weight loss. High initial levels of self-efficacy may be characteristic of Web-health users interested in online interventions and may alter the function of SCT in these programs. Researchers may find that, although increased self-efficacy enhances program outcomes, participants whose self-efficacy is tempered by online interventions may still benefit.
Trial Registration NCT00128570; (Archived by WebCite at
PMCID: PMC3221349  PMID: 21447470
Internet users; dietary habits; physical activity; psychosocial aspects; self-efficacy; social support; self-regulation
11.  Physical Activity Attenuates the Influence of FTO Variants on Obesity Risk: A Meta-Analysis of 218,166 Adults and 19,268 Children 
Kilpeläinen, Tuomas O. | Qi, Lu | Brage, Soren | Sharp, Stephen J. | Sonestedt, Emily | Demerath, Ellen | Ahmad, Tariq | Mora, Samia | Kaakinen, Marika | Sandholt, Camilla Helene | Holzapfel, Christina | Autenrieth, Christine S. | Hyppönen, Elina | Cauchi, Stéphane | He, Meian | Kutalik, Zoltan | Kumari, Meena | Stančáková, Alena | Meidtner, Karina | Balkau, Beverley | Tan, Jonathan T. | Mangino, Massimo | Timpson, Nicholas J. | Song, Yiqing | Zillikens, M. Carola | Jablonski, Kathleen A. | Garcia, Melissa E. | Johansson, Stefan | Bragg-Gresham, Jennifer L. | Wu, Ying | van Vliet-Ostaptchouk, Jana V. | Onland-Moret, N. Charlotte | Zimmermann, Esther | Rivera, Natalia V. | Tanaka, Toshiko | Stringham, Heather M. | Silbernagel, Günther | Kanoni, Stavroula | Feitosa, Mary F. | Snitker, Soren | Ruiz, Jonatan R. | Metter, Jeffery | Larrad, Maria Teresa Martinez | Atalay, Mustafa | Hakanen, Maarit | Amin, Najaf | Cavalcanti-Proença, Christine | Grøntved, Anders | Hallmans, Göran | Jansson, John-Olov | Kuusisto, Johanna | Kähönen, Mika | Lutsey, Pamela L. | Nolan, John J. | Palla, Luigi | Pedersen, Oluf | Pérusse, Louis | Renström, Frida | Scott, Robert A. | Shungin, Dmitry | Sovio, Ulla | Tammelin, Tuija H. | Rönnemaa, Tapani | Lakka, Timo A. | Uusitupa, Matti | Rios, Manuel Serrano | Ferrucci, Luigi | Bouchard, Claude | Meirhaeghe, Aline | Fu, Mao | Walker, Mark | Borecki, Ingrid B. | Dedoussis, George V. | Fritsche, Andreas | Ohlsson, Claes | Boehnke, Michael | Bandinelli, Stefania | van Duijn, Cornelia M. | Ebrahim, Shah | Lawlor, Debbie A. | Gudnason, Vilmundur | Harris, Tamara B. | Sørensen, Thorkild I. A. | Mohlke, Karen L. | Hofman, Albert | Uitterlinden, André G. | Tuomilehto, Jaakko | Lehtimäki, Terho | Raitakari, Olli | Isomaa, Bo | Njølstad, Pål R. | Florez, Jose C. | Liu, Simin | Ness, Andy | Spector, Timothy D. | Tai, E. Shyong | Froguel, Philippe | Boeing, Heiner | Laakso, Markku | Marmot, Michael | Bergmann, Sven | Power, Chris | Khaw, Kay-Tee | Chasman, Daniel | Ridker, Paul | Hansen, Torben | Monda, Keri L. | Illig, Thomas | Järvelin, Marjo-Riitta | Wareham, Nicholas J. | Hu, Frank B. | Groop, Leif C. | Orho-Melander, Marju | Ekelund, Ulf | Franks, Paul W. | Loos, Ruth J. F.
PLoS Medicine  2011;8(11):e1001116.
Ruth Loos and colleagues report findings from a meta-analysis of multiple studies examining the extent to which physical activity attenuates effects of a specific gene variant, FTO, on obesity in adults and children. They report a fairly substantial attenuation by physical activity on the effects of this genetic variant on the risk of obesity in adults.
The FTO gene harbors the strongest known susceptibility locus for obesity. While many individual studies have suggested that physical activity (PA) may attenuate the effect of FTO on obesity risk, other studies have not been able to confirm this interaction. To confirm or refute unambiguously whether PA attenuates the association of FTO with obesity risk, we meta-analyzed data from 45 studies of adults (n = 218,166) and nine studies of children and adolescents (n = 19,268).
Methods and Findings
All studies identified to have data on the FTO rs9939609 variant (or any proxy [r2>0.8]) and PA were invited to participate, regardless of ethnicity or age of the participants. PA was standardized by categorizing it into a dichotomous variable (physically inactive versus active) in each study. Overall, 25% of adults and 13% of children were categorized as inactive. Interaction analyses were performed within each study by including the FTO×PA interaction term in an additive model, adjusting for age and sex. Subsequently, random effects meta-analysis was used to pool the interaction terms. In adults, the minor (A−) allele of rs9939609 increased the odds of obesity by 1.23-fold/allele (95% CI 1.20–1.26), but PA attenuated this effect (pinteraction  = 0.001). More specifically, the minor allele of rs9939609 increased the odds of obesity less in the physically active group (odds ratio  = 1.22/allele, 95% CI 1.19–1.25) than in the inactive group (odds ratio  = 1.30/allele, 95% CI 1.24–1.36). No such interaction was found in children and adolescents.
The association of the FTO risk allele with the odds of obesity is attenuated by 27% in physically active adults, highlighting the importance of PA in particular in those genetically predisposed to obesity.
Please see later in the article for the Editors' Summary
Editors’ Summary
Two in three Americans are overweight, of whom half are obese, and the trend towards increasing obesity is now seen across developed and developing countries. There has long been interest in understanding the impact of genes and environment when it comes to apportioning responsibility for obesity. Carrying a change in the FTO gene is common (found in three-quarters of Europeans and North Americans) and is associated with a 20%–30% increased risk of obesity. Some overweight or obese individuals may feel that the dice are loaded and there is little point in fighting the fat; it has been reported that those made aware of their genetic susceptibility to obesity may still choose a poor diet. A similar fatalism may occur when overweight and obese people consider physical activity. But disentangling the influence of physical activity on those genetically susceptible to obesity from other factors that might impact weight is not straightforward, as it requires large sample sizes, could be subject to publication bias, and may rely on less than ideal self-reporting methods.
Why Was This Study Done?
The public health ramifications of understanding the interaction between genetic susceptibility to obesity and physical activity are considerable. Tackling the rising prevalence of obesity will inevitably include interventions principally aimed at changing dietary intake and/or increasing physical activity, but the evidence for these with regards to those genetically susceptible has been lacking to date. The authors of this paper set out to explore the interaction between the commonest genetic susceptibility trait and physical activity using a rigorous meta-analysis of a large number of studies.
What Did the Researchers Do and Find?
The authors were concerned that a meta-analysis of published studies would be limited both by the data available to them and by possible bias. Instead of this more widely used approach, they took the literature search as their starting point, identified other studies through their collaborators’ network, and then undertook a meta-analysis of all available studies using a new and standardized analysis plan. This entailed an extremely large number of authors mining their data afresh to extract the relevant data points to enable such a meta-analysis. Physical activity was identified in the original studies in many different ways, including by self-report or by using an external measure of activity or heart rate. In order to perform the meta-analysis, participants were labeled as physically active or inactive in each study. For studies that had used a continuous scale, the authors decided that the bottom 20% of the participants were inactive (10% for children and adolescents). Using data from over 218,000 adults, the authors found that carrying a copy of the susceptibility gene increased the odds of obesity by 1.23-fold. But the size of this influence was 27% less in the genetically susceptible adults who were physically active (1.22-fold) compared to those who were physically inactive (1.30-fold). In a smaller study of about 19,000 children, no such effect of physical activity was seen.
What Do these Findings Mean?
This study demonstrates that people who carry the susceptibility gene for obesity can benefit from physical activity. This should inform health care professionals and the wider public that the view of genetically determined obesity not being amenable to exercise is incorrect and should be challenged. Dissemination, implementation, and ensuring uptake of effective physical activity programs remains a challenge and deserves further consideration. That the researchers treated “physically active” as a yes/no category, and how they categorized individuals, could be criticized, but this was done for pragmatic reasons, as a variety of means of assessing physical activity were used across the studies. It is unlikely that the findings would have changed if the authors had used a different method of defining physically active. Most of the studies included in the meta-analysis looked at one time point only; information about the influence of physical activity on weight changes over time in genetically susceptible individuals is only beginning to emerge.
Additional Information
Please access these websites via the online version of this summary at
This study is further discussed in a PLoS Medicine Perspective by Lennert Veerman
The US Centers for Disease Control and Prevention provides obesity-related statistics, details of prevention programs, and an overview on public health strategy in the United States
A more worldwide view is given by the World Health Organization
The UK National Health Service website gives information on physical activity guidelines for different age groups, while similar information can also be found from US sources
PMCID: PMC3206047  PMID: 22069379
12.  Effect of Physical Inactivity on the Oxidation of Saturated and Monounsaturated Dietary Fatty Acids: Results of a Randomized Trial  
PLoS Clinical Trials  2006;1(5):e27.
Changes in the way dietary fat is metabolized can be considered causative in obesity. The role of sedentary behavior in this defect has not been determined. We hypothesized that physical inactivity partitions dietary fats toward storage and that a resistance exercise training program mitigates storage.
We used bed rest, with randomization to resistance training, as a model of physical inactivity.
The trial took place at the Space Clinic (Toulouse, France).
A total of 18 healthy male volunteers, of mean age ± standard deviation 32.6 ± 4.0 y and body mass index 23.6 ± 0.7 kg/m2, were enrolled.
An initial 15 d of baseline data collection were followed by 3 mo of strict bed-rest alone (control group, n = 9) or with the addition of supine resistance exercise training every 3 d (exercise group, n = 9).
Outcome measures:
Oxidation of labeled [d31]palmitate (the main saturated fatty acid of human diet) and [1-13C]oleate (the main monounsaturated fatty acid), body composition, net substrate use, and plasma hormones and metabolites were measured.
Between-group comparisons showed that exercise training did not affect oxidation of both oleate (mean difference 5.6%; 95% confidence interval [95% CI], −3.3% to 14.5%; p = 0.20) and palmitate (mean difference −0.2%; 95% CI, −4.1% to 3.6%; p = 0.89). Within-group comparisons, however, showed that inactivity changed oxidation of palmitate in the control group by −11.0% (95% CI, −19.0% to −2.9%; p = 0.01) and in the exercise group by −11.3% (95% CI, −18.4% to −4.2%; p = 0.008). In contrast, bed rest did not significantly affect oleate oxidation within groups. In the control group, the mean difference in oleate oxidation was 3.2% (95% CI, −4.2% to 10.5%; p = 0.34) and 6.8% (95% CI, −1.2% to 14.7%; p = 0.08) in the exercise group.
Independent of changes in energy balance (intake and/or output), physical inactivity decreased the oxidation of saturated but not monounsaturated dietary fat. The effect is apparently not compensated by resistance exercise training. These results suggest that Mediterranean diets should be recommended in sedentary subjects and recumbent patients.
Editorial Commentary
Background: Obesity is an important contributor to the burden of chronic diseases, particularly type II diabetes, cardiovascular disease, hypertension, and stroke. Being inactive is a risk factor for all of these conditions. However, the physiological effects of inactivity are not well understood. In this trial, supported by the European Space Agency, a group of researchers aimed to further understand the effects of physical inactivity on the way that fat from the diet is metabolized (i.e., broken down to generate energy). 18 healthy male volunteers were randomized into two groups, both of whom underwent 90 days of bed rest, aiming to mimic sedentary behavior. One group also received an exercise training program during the 90 days' bed rest. The researchers examined to what extent two different types of fatty acids common in the diet were metabolized over the duration of the trial: oleate (monounsaturated fat) and palmitate (saturated fat). As secondary objectives of the study, body weight, water, fat, and energy expenditure were also examined in the participants.
What this trial shows: The researchers did not see any statistically significant changes between the groups—that is, participants receiving bed rest, and those receiving bed rest plus exercise training—for any of the primary or secondary outcomes, except for resting metabolic rate, which was higher in the exercise group. However, they did see physiologically relevant changes in fat metabolism of one of the fatty acids, palmitate, over the course of the trial within both groups studied. Although metabolism of oleate (monounsaturated fat) did not show significant changes over the course of the trial, metabolism of palmitate (saturated fat) dropped by nearly 10% in both groups (bed rest, and bed rest plus exercise).
Strengths and limitations: The study design was appropriate to the questions being posed, and the techniques for examining fat metabolism were relevant. Although the number of participants was very small, this problem is true of many such studies due to the cost and complexity of the interventions. The model for inactivity used in this trial—90 days' bed rest—is very extreme. Very few studies of this type have been performed, with most of the evidence relating to activity and fat handling coming from training studies in otherwise sedentary people.
Contribution to the evidence: It is already known that physical activity has numerous health benefits, including the prevention of obesity. This trial provides data showing that inactivity lowers the ability to metabolize fat, specifically saturated fat, from the diet, which would therefore be more likely to be stored in the body.
PMCID: PMC1584255  PMID: 17016547
13.  Psychosocial correlates of eating behavior in children and adolescents: a review 
Understanding the correlates of dietary intake is necessary in order to effectively promote healthy dietary behavior among children and adolescents. A literature review was conducted on the correlates of the following categories of dietary intake in children and adolescents: Fruit, Juice and Vegetable Consumption, Fat in Diet, Total Energy Intake, Sugar Snacking, Sweetened Beverage Consumption, Dietary Fiber, Other Healthy Dietary Consumption, and Other Less Healthy Dietary Consumption in children and adolescents.
Cross-sectional and prospective studies were identified from PubMed, PsycINFO and PsycArticles by using a combination of search terms. Quantitative research examining determinants of dietary intake among children and adolescents aged 3–18 years were included. The selection and review process yielded information on country, study design, population, instrument used for measuring intake, and quality of research study.
Seventy-seven articles were included. Many potential correlates have been studied among children and adolescents. However, for many hypothesized correlates substantial evidence is lacking due to a dearth of research. The correlates best supported by the literature are: perceived modeling, dietary intentions, norms, liking and preferences. Perceived modeling and dietary intentions have the most consistent and positive associations with eating behavior. Norms, liking, and preferences were also consistently and positively related to eating behavior in children and adolescents. Availability, knowledge, outcome expectations, self-efficacy and social support did not show consistent relationships across dietary outcomes.
This review examined the correlates of various dietary intake; Fruit, Juice and Vegetable Consumption, Fat in Diet, Total Energy Intake, Sugar Snacking, Sweetened Beverage Consumption, Dietary Fiber, Other Healthy Dietary Consumption, and Other Less Healthy Dietary Consumption in cross-sectional and prospective studies for children and adolescents. The correlates most consistently supported by evidence were perceived modeling, dietary intentions, norms, liking and preferences. More prospective studies on the psychosocial determinants of eating behavior using broader theoretical perspectives should be examined in future research.
PMCID: PMC3224918  PMID: 19674467
14.  Food Pricing Strategies, Population Diets, and Non-Communicable Disease: A Systematic Review of Simulation Studies 
PLoS Medicine  2012;9(12):e1001353.
A systematic review of simulation studies conducted by Helen Eyles and colleagues examines the association between food pricing strategies and food consumption and health and disease outcomes.
Food pricing strategies have been proposed to encourage healthy eating habits, which may in turn help stem global increases in non-communicable diseases. This systematic review of simulation studies investigates the estimated association between food pricing strategies and changes in food purchases or intakes (consumption) (objective 1); Health and disease outcomes (objective 2), and whether there are any differences in these outcomes by socio-economic group (objective 3).
Methods and Findings
Electronic databases, Internet search engines, and bibliographies of included studies were searched for articles published in English between 1 January 1990 and 24 October 2011 for countries in the Organisation for Economic Co-operation and Development. Where ≥3 studies examined the same pricing strategy and consumption (purchases or intake) or health outcome, results were pooled, and a mean own-price elasticity (own-PE) estimated (the own-PE represents the change in demand with a 1% change in price of that good). Objective 1: pooled estimates were possible for the following: (1) taxes on carbonated soft drinks: own-PE (n = 4 studies), −0.93 (range, −0.06, −2.43), and a modelled −0.02% (−0.01%, −0.04%) reduction in energy (calorie) intake for each 1% price increase (n = 3 studies); (2) taxes on saturated fat: −0.02% (−0.01%, −0.04%) reduction in energy intake from saturated fat per 1% price increase (n = 5 studies); and (3) subsidies on fruits and vegetables: own-PE (n = 3 studies), −0.35 (−0.21, −0.77). Objectives 2 and 3: variability of food pricing strategies and outcomes prevented pooled analyses, although higher quality studies suggested unintended compensatory purchasing that could result in overall effects being counter to health. Eleven of 14 studies evaluating lower socio-economic groups estimated that food pricing strategies would be associated with pro-health outcomes. Food pricing strategies also have the potential to reduce disparities.
Based on modelling studies, taxes on carbonated drinks and saturated fat and subsidies on fruits and vegetables would be associated with beneficial dietary change, with the potential for improved health. Additional research into possible compensatory purchasing and population health outcomes is needed.
Please see later in the article for the Editors' Summary
Editors' Summary
For the first time in human history, non-communicable diseases (NCDs) are killing more people than infectious diseases. Every year, more than 35 million people die from NCDs—nearly two-thirds of the world's annual deaths. More than 80% of these deaths are in developing countries, where a third of NCD-related deaths occur in people younger than 60 years old. And NCDs are not just a growing global public health emergency. They are also financially costly because they reduce productivity and increase calls on health care systems worldwide. Cardiovascular diseases (conditions that affect the heart and circulation such as heart attacks and stroke), cancers, diabetes, and chronic respiratory diseases (long-term diseases that affect the lungs and airways) are responsible for most NCD-related illnesses and death. The main behavioral risk factors for all these diseases are tobacco use, harmful use of alcohol, physical inactivity, and unhealthy diets (diets that have a low fruit and vegetable intake and high saturated fat and salt intakes).
Why Was This Study Done?
Improvements in population diets and reductions in salt intake are crucial for the control and prevention of NCDs, but how can these behavioral changes be encouraged? One potential but poorly studied strategy is food pricing—the introduction of taxes on unhealthy foods (for example, foods containing high levels of saturated fat) and subsidies on healthy foods (for example, foods high in fiber). However, although a tax on soft drinks, for example, might decrease purchases of these high-sugar drinks, it might also increase purchases of fruit juices, which contain just as much sugar and energy as soft drinks (“compensatory purchasing”), and thus undermine the intended health impact of the tax. Because randomized controlled trials of the effects of food pricing strategies are difficult to undertake, many researchers have turned to mathematical models (sets of equations that quantify relationships between interventions and outcomes) to provide the evidence needed to inform policy decisions on food taxes and subsidies. In this systematic review (a study that uses predefined criteria to identify all the research on a given topic), Helen Eyles and colleagues investigate the association between food pricing strategies and food consumption and NCDs by analyzing the results of published mathematical modeling studies of food pricing interventions.
What Did the Researchers Do and Find?
The researchers identified 32 studies that met their predefined inclusion criteria, which included publication by researchers in a member country of the Organisation for Economic Co-operation and Development (a group of largely developed countries that promotes global development). Most of the studies were of low to moderate quality and provided uncertain and varying estimates of the impact of pricing on food consumption. Where three or more studies examined the same pricing strategy and consumption or health outcome, the researchers calculated the average change in demand for a food in response to changes in its price (“own-price elasticity”). For taxes on carbonated soft drinks, the average own-price elasticity was −0.93; that is, the models predicted that a 1% increase in the price of soft drinks would decrease consumption by 0.93%. The modeled reduction in the proportion of energy intake from saturated fat resulting from a 1% increase in the price of saturated fats was 0.02%. Finally, although the researchers' analysis suggested that for each 1% reduction in the price of fruits and vegetables, consumption would increase by 0.35%, they also found evidence that such a subsidy might result in compensatory purchasing, such as a reduction in fish purchases.
What Do These Findings Mean?
These findings suggest that pricing strategies have the potential to produce improvements in population diets, at least in developed countries, but also highlight the need for more research in this area. Notably, the researchers found insufficient data to allow them to quantify the effects of pricing strategies on health or to analyze whether the effect of pricing strategies is likely vary between socio-economic groups. Given their findings, the researchers suggest that future modeling studies should include better assessments of the unintended effects of compensatory purchasing and should examine the potential impact of food pricing strategies on long-term health and NCD-related deaths. Finally, they suggest that robust evaluations should be built into the implementation of food pricing policies to answer some of the outstanding questions about this potential strategy for reducing the global burden of NCDs.
Additional Information
Please access these websites via the online version of this summary at
The US Centers for Disease Control and Prevention provides information on all aspects of healthy living, on chronic diseases and health promotion, and on non-communicable diseases around the world
The Global Noncommunicable Disease Network (NCDnet) aims to help low- and middle-income countries reduce NCD-related illnesses and death through implementation of the 2008-2013 Action Plan for the Global Strategy for the Prevention and Control of Noncommunicable Diseases (also available in French); NCDnet's Face to face with chronic disease webpage is a selection of personal stories from around the world about dealing with NCDs
The American Heart Association and the American Cancer Society provide information on many important risk factors for non-communicable diseases and include some personal stories about keeping healthy
PMCID: PMC3519906  PMID: 23239943
15.  Familial correlates of adolescent girls' physical activity, television use, dietary intake, weight, and body composition 
The family environment offers several opportunities through which to improve adolescents' weight and weight-related behaviors. This study aims to examine the cross-sectional relationships between multiple factors in the family environment and physical activity (PA), television use (TV), soft drink intake, fruit and vegetable (FV) intake, body mass index (BMI), and body composition among a sample of sociodemographically-diverse adolescent girls.
Subjects included girls (mean age = 15.7), 71% of whom identified as a racial/ethnic minority, and one of their parents (dyad n = 253). Parents completed surveys assessing factors in the family environment including familial support for adolescents' PA, healthful dietary intake, and limiting TV use; parental modeling of behavior; and resources in the home such as availability of healthful food. Girls' PA and TV use were measured by 3-Day Physical Activity Recall (3DPAR) and dietary intake by survey measures. BMI was measured by study staff, and body fat by dual-energy X-ray absorptiometry (DXA). Hierarchical linear regression models tested individual and mutually-adjusted relationships between family environment factors and girls' outcomes.
In the individual models, positive associations were observed between family support for PA and girls' total PA (p = .011) and moderate-to-vigorous PA (p=.016), home food availability and girls' soft drink (p < .001) and FV (p < .001) intake, and family meal frequency and girls' FV intake (p = .023). Across the individual and mutually-adjusted models, parental modeling of PA, TV, and soft drink and FV intake was consistently associated with girls' behavior.
Helping parents improve their physical activity and dietary intake, as well as reduce time watching television, may be an effective way to promote healthful behaviors and weight among adolescent girls.
PMCID: PMC3078831  PMID: 21453516
16.  Perceived Environmental Church Support is Associated with Dietary Practices among African American Adults 
A unique strength of the African American community is the importance of the church and faith. Interventions promoting health may want to build on these strengths by developing faith-based interventions that encourage churches to create an environment that supports behavior change.
To examine the relationship between perceived environmental church support for healthy eating and intake of fruit and vegetables and fat and fiber-related behaviors, and to examine if these relationships differ by gender.
A cross-sectional study in which participants completed self-report dietary and perceived church support measures prior to the initiation of an intervention. Relationships between fruit and vegetable consumption, fat and fiber-related behaviors, and perceived church support (total, written informational, spoken informational, instrumental [fruit and vegetable consumption only]), along with Support x Gender interactions were examined.
Participants were 1136 African American church members from four geographically-defined districts in South Carolina.
Statistical Analyses
Multiple regression models controlling for gender, age, years of education, health rating, and body mass index using SAS PROC MIXED. A separate model was conducted for each measure of perceived church support and each type of healthy eating index.
Perceived total church support and perceived written and spoken informational church support were related to significantly higher fruit and vegetable intake and more favorable fiber-related behaviors, whereas only perceived total and perceived written informational support were associated with more low-fat dietary behaviors. Perceived instrumental church support was not associated with fruit and vegetable consumption. No gender differences were found.
The social and physical church environment may be important factors influencing the dietary habits of its members. Future faith-based interventions should further explore the role of the church environment in improving the dietary practices of its members.
PMCID: PMC3103703  PMID: 21616203
Dietary Practices; Faith-based; African American Adults; Church Support
17.  Make Better Choices (MBC): Study design of a randomized controlled trial testing optimal technology-supported change in multiple diet and physical activity risk behaviors 
BMC Public Health  2010;10:586.
Suboptimal diet and physical inactivity are prevalent, co-occurring chronic disease risk factors, yet little is known about how to maximize multiple risk behavior change. Make Better Choices, a randomized controlled trial, tests competing hypotheses about the optimal way to promote healthy change in four bundled risk behaviors: high saturated fat intake, low fruit and vegetable intake, low physical activity, and high sedentary leisure screen time. The study aim is to determine which combination of two behavior change goals - one dietary, one activity - yields greatest overall healthy lifestyle change.
Adults (n = 200) with poor quality diet and sedentary lifestyle will be recruited and screened for study eligibility. Participants will be trained to record their diet and activities onto a personal data assistant, and use it to complete two weeks of baseline. Those who continue to show all four risk behaviors after baseline recording will be randomized to one of four behavior change prescriptions: 1) increase fruits and vegetables and increase physical activity, 2) decrease saturated fat and increase physical activity, 3) increase fruits and vegetable and decrease saturated fat, or 4) decrease saturated fat and decrease sedentary activity. They will use decision support feedback on the personal digital assistant and receive counseling from a coach to alter their diet and activity during a 3-week prescription period when payment is contingent upon meeting behavior change goals. They will continue recording on an intermittent schedule during a 4.5-month maintenance period when payment is not contingent upon goal attainment. The primary outcome is overall healthy lifestyle change, aggregated across all four risk behaviors.
The Make Better Choices trial tests a disseminable lifestyle intervention supported by handheld technology. Findings will fill a gap in knowledge about optimal goal prescription to facilitate simultaneous diet and activity change. Results will shed light on which goal prescription maximizes healthful lifestyle change.
Trial Registration
Clinical Trials Gov. Identifier NCT00113672
PMCID: PMC2955698  PMID: 20920275
18.  Short- and Medium-Term Efficacy of a Web-Based Computer-Tailored Nutrition Education Intervention for Adults Including Cognitive and Environmental Feedback: Randomized Controlled Trial 
Web-based, computer-tailored nutrition education interventions can be effective in modifying self-reported dietary behaviors. Traditional computer-tailored programs primarily targeted individual cognitions (knowledge, awareness, attitude, self-efficacy). Tailoring on additional variables such as self-regulation processes and environmental-level factors (the home food environment arrangement and perception of availability and prices of healthy food products in supermarkets) may improve efficacy and effect sizes (ES) of Web-based computer-tailored nutrition education interventions.
This study evaluated the short- and medium-term efficacy and educational differences in efficacy of a cognitive and environmental feedback version of a Web-based computer-tailored nutrition education intervention on self-reported fruit, vegetable, high-energy snack, and saturated fat intake compared to generic nutrition information in the total sample and among participants who did not comply with dietary guidelines (the risk groups).
A randomized controlled trial was conducted with a basic (tailored intervention targeting individual cognition and self-regulation processes; n=456), plus (basic intervention additionally targeting environmental-level factors; n=459), and control (generic nutrition information; n=434) group. Participants were recruited from the general population and randomly assigned to a study group. Self-reported fruit, vegetable, high-energy snack, and saturated fat intake were assessed at baseline and at 1- (T1) and 4-months (T2) postintervention using online questionnaires. Linear mixed model analyses examined group differences in change over time. Educational differences were examined with group×time×education interaction terms.
In the total sample, the basic (T1: ES=–0.30; T2: ES=–0.18) and plus intervention groups (T1: ES=–0.29; T2: ES=–0.27) had larger decreases in high-energy snack intake than the control group. The basic version resulted in a larger decrease in saturated fat intake than the control intervention (T1: ES=–0.19; T2: ES=–0.17). In the risk groups, the basic version caused larger decreases in fat (T1: ES=–0.28; T2: ES=–0.28) and high-energy snack intake (T1: ES=–0.34; T2: ES=–0.20) than the control intervention. The plus version resulted in a larger increase in fruit (T1: ES=0.25; T2: ES=0.37) and a larger decrease in high-energy snack intake (T1: ES=–0.38; T2: ES=–0.32) than the control intervention. For high-energy snack intake, educational differences were found. Stratified analyses showed that the plus version was most effective for high-educated participants.
Both intervention versions were more effective in improving some of the self-reported dietary behaviors than generic nutrition information, especially in the risk groups, among both higher- and lower-educated participants. For fruit intake, only the plus version was more effective than providing generic nutrition information. Although feasible, incorporating environmental-level information is time-consuming. Therefore, the basic version may be more feasible for further implementation, although inclusion of feedback on the arrangement of the home food environment and on availability and prices may be considered for fruit and, for high-educated people, for high-energy snack intake.
Trial Registration
Netherlands Trial Registry NTR3396; (Archived by WebCite at
PMCID: PMC4319071  PMID: 25599828
cognitive feedback; environmental feedback; self-regulation; computer tailoring; nutrition education; fruit consumption; vegetable consumption; fat consumption; snack consumption
19.  Physical activity, sedentary behaviors and dietary habits among Saudi adolescents relative to age, gender and region 
Few lifestyle factors have been simultaneously studied and reported for Saudi adolescents. Therefore, the purpose of the present study was to report on the prevalence of physical activity, sedentary behaviors and dietary habits among Saudi adolescents and to examine the interrelationships among these factors using representative samples drawn from three major cities in Saudi Arabia.
This school-based cross-sectional study was conducted during the years 2009-2010 in three cities: Al-Khobar, Jeddah and Riyadh. The participants were 2908 secondary-school males (1401) and females (1507) aged 14-19 years, randomly selected using a multistage stratified sampling technique. Measurements included weight, height, sedentary behaviors (TV viewing, playing video games and computer use), physical activity using a validated questionnaire and dietary habits.
A very high proportion (84% for males and 91.2% for females) of Saudi adolescents spent more than 2 hours on screen time daily and almost half of the males and three-quarters of the females did not meet daily physical activity guidelines. The majority of adolescents did not have a daily intake of breakfast, fruit, vegetables and milk. Females were significantly (p < 0.05) more sedentary, much less physically active, especially with vigorous physical activity, and there were fewer days per week when they consumed breakfast, fruit, milk and diary products, sugar-sweetened drinks, fast foods and energy drinks than did males. However, the females' intake of French fries and potato chips, cakes and donuts, and candy and chocolate was significantly (p < 0.05) higher than the males'. Screen time was significantly (p < 0.05) correlated inversely with the intake of breakfast, vegetables and fruit. Physical activity had a significant (p < 0.05) positive relationship with fruit and vegetable intake but not with sedentary behaviors.
The high prevalence of sedentary behaviors, physical inactivity and unhealthy dietary habits among Saudi adolescents is a major public health concern. There is an urgent need for national policy promoting active living and healthy eating and reducing sedentary behaviors among children and adolescents in Saudi Arabia.
PMCID: PMC3339333  PMID: 22188825
Physical activity; sedentary behaviors; dietary habits; lifestyle factors; adolescents; Saudi Arabia
20.  Association of breakfast intake with obesity, dietary and physical activity behavior among urban school-aged adolescents in Delhi, India: results of a cross-sectional study 
BMC Public Health  2012;12:881.
In developed countries, regular breakfast consumption is inversely associated with excess weight and directly associated with better dietary and improved physical activity behaviors. Our objective was to describe the frequency of breakfast consumption among school-going adolescents in Delhi and evaluate its association with overweight and obesity as well as other dietary, physical activity, and sedentary behaviors.
Design: Cross-sectional study. Setting: Eight schools (Private and Government) of Delhi in the year 2006. Participants: 1814 students from 8th and 10th grades; response rate was 87.2%; 55% were 8th graders, 60% were boys and 52% attended Private schools. Main outcome measures: Body mass index, self-reported breakfast consumption, diet and physical activity related behaviors, and psychosocial factors. Data analysis: Mixed effects regression models were employed, adjusting for age, gender, grade level and school type (SES).
Significantly more Government school (lower SES) students consumed breakfast daily as compared to Private school (higher SES) students (73.8% vs. 66.3%; p<0.01). More 8th graders consumed breakfast daily vs.10th graders (72.3% vs. 67.0%; p<0.05). A dose–response relationship was observed such that overall prevalence of overweight and obesity among adolescents who consumed breakfast daily (14.6%) was significantly lower vs. those who only sometimes (15.2%) or never (22.9%) consumed breakfast (p<0.05 for trend). This relationship was statistically significant for boys (15.4 % vs. 16.5% vs. 26.0; p<0.05 for trend) but not for girls. Intake of dairy products, fruits and vegetables was 5.5 (95% CI 2.4-12.5), 1.7 (95% CI 1.1-2.5) and 2.2 (95% CI 1.3-3.5) times higher among those who consumed breakfast daily vs. those who never consumed breakfast. Breakfast consumption was associated with greater physical activity vs. those who never consumed breakfast. Positive values and beliefs about healthy eating; body image satisfaction; and positive peer and parental influence were positively associated with daily breakfast consumption, while depression was negatively associated.
Daily breakfast consumption is associated with less overweight and obesity and with healthier dietary- and physical activity-related behaviors among urban Indian students. Although prospective studies should confirm the present results, intervention programs to prevent or treat childhood obesity in India should consider emphasizing regular breakfast consumption.
PMCID: PMC3549919  PMID: 23075030
Breakfast; Obesity; Adolescent; Diet; Physical activity; Behavior
21.  Explaining the effects of a 1-year intervention promoting a low fat diet in adolescent girls: a mediation analysis 
Although it is important to investigate how interventions work, no formal mediation analyses have been conducted to explain behavioral outcomes in school-based fat intake interventions in adolescents. The aim of the present study was to examine mediation effects of changes in psychosocial determinants of dietary fat intake (attitude, social support, self-efficacy, perceived benefits and barriers) on changes in fat intake in adolescent girls.
Data from a 1-year prospective intervention study were used. A random sample of 804 adolescent girls was included in the study. Girls in the intervention group (n = 415) were exposed to a multi-component school-based intervention program, combining environmental changes with a computer tailored fat intake intervention and parental support. Fat intake and psychosocial determinants of fat intake were measured with validated self-administered questionnaires. To assess mediating effects, a product-of-coefficient test, appropriate for cluster randomized controlled trials, was used.
None of the examined psychosocial factors showed a reliable mediating effect on changes in fat intake. The single-mediator model revealed a statistically significant suppression effect of perceived barriers on changes in fat intake (p = 0.011). In the multiple-mediator model, this effect was no longer significant, which was most likely due to changes in perceived barriers being moderately related to changes in self-efficacy (-0.30) and attitude (-0.25). The overall mediated-suppressed effect of the examined psychosocial factors was virtually zero (total mediated effect = 0.001; SE = 7.22; p = 0.992).
Given the lack of intervention effects on attitudes, social support, self-efficacy and perceived benefits and barriers, it is suggested that future interventions should focus on the identification of effective strategies for changing these theoretical mediators in the desired direction. Alternatively, it could be argued that these constructs need not be targeted in interventions aimed at adolescents, as they may not be responsible for the intervention effects on fat intake. To draw any conclusions regarding mediators of fat-intake change in adolescent' girls and regarding optimal future intervention strategies, more systematic research on the mediating properties of psychosocial variables is needed.
PMCID: PMC2200660  PMID: 17996087
22.  Family Functioning: Associations with Weight Status, Eating Behaviors, and Physical Activity in Adolescents 
This paper examines the relationship between family functioning (e.g. communication, closeness, problem solving, behavioral control) and adolescent weight status and relevant eating and physical activity behaviors.
Data are from EAT 2010 (Eating and Activity in Teens), a population-based study that assessed eating and activity among socioeconomically and racially/ethnically diverse youth (n = 2,793). Adolescents (46.8% boys, 53.2% girls) completed anthropometric assessments and surveys at school in 2009–2010. Multiple linear regression was used to test the relationship between family functioning and adolescent weight, dietary intake, family meal patterns, and physical activity. Additional regression models were fit to test for interactions by race/ethnicity.
For adolescent girls, higher family functioning was associated with lower body mass index z-score and percent overweight, less sedentary behavior, higher intake of fruits and vegetables, and more frequent family meals and breakfast consumption. For adolescent boys, higher family functioning was associated with more physical activity, less sedentary behavior, less fast food consumption, and more frequent family meals and breakfast consumption. There was one significant interaction by race/ethnicity for family meals; the association between higher family functioning and more frequent family meals was stronger for non-white boys compared to white boys. Overall, strengths of associations tended to be small with effect sizes ranging from - 0.07 to 0.31 for statistically significant associations.
Findings suggest that family functioning may be protective for adolescent weight and weight-related health behaviors across all race/ethnicities, although assumptions regarding family functioning in the homes of overweight children should be avoided given small effect sizes.
PMCID: PMC3580029  PMID: 23299010
Family Functioning; Adolescent Obesity; Dietary Intake; Family Meals; Physical Activity
23.  Relationship between self-reported dietary intake and physical activity levels among adolescents: The HELENA study 
Evidence suggests possible synergetic effects of multiple lifestyle behaviors on health risks like obesity and other health outcomes. Therefore it is important to investigate associations between dietary and physical activity behavior, the two most important lifestyle behaviors influencing our energy balance and body composition. The objective of the present study is to describe the relationship between energy, nutrient and food intake and the physical activity level among a large group of European adolescents.
The study comprised a total of 2176 adolescents (46.2% male) from ten European cities participating in the HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence) study. Dietary intake and physical activity were assessed using validated 24-h dietary recalls and self-reported questionnaires respectively. Analyses of covariance (ANCOVA) were used to compare the energy and nutrient intake and the food consumption between groups of adolescents with different physical activity levels (1st to 3rd tertile).
In both sexes no differences were found in energy intake between the levels of physical activity. The most active males showed a higher intake of polysaccharides, protein, water and vitamin C and a lower intake of saccharides compared to less active males. Females with the highest physical activity level consumed more polysaccharides compared to their least active peers. Male and female adolescents with the highest physical activity levels, consumed more fruit and milk products and less cheese compared to the least active adolescents. The most active males showed higher intakes of vegetables and meat, fish, eggs, meat substitutes and vegetarian products compared to the least active ones. The least active males reported the highest consumption of grain products and potatoes. Within the female group, significantly lower intakes of bread and cereal products and spreads were found for those reporting to spend most time in moderate to vigorous physical activity. The consumption of foods from the remaining food groups, did not differ between the physical activity levels in both sexes.
It can be concluded that dietary habits diverge between adolescents with different self-reported physical activity levels. For some food groups a difference in intake could be found, which were reflected in differences in some nutrient intakes. It can also be concluded that physically active adolescents are not always inclined to eat healthier diets than their less active peers.
PMCID: PMC3045277  PMID: 21294914
24.  Daily Self-Monitoring of Body Weight, Step Count, Fruit/Vegetable Intake and Water Consumption: A Feasible and Effective Long-Term Weight Loss Maintenance Approach 
Maintenance of weight loss remains a challenge for most individuals, thus practical and effective weight loss maintenance (WTLM) strategies are needed. A two-group (WEV versus WEV+) 12-month WTLM intervention trial was conducted (June 2007–February 2010) to determine the feasibility and effectiveness of weight loss maintenance intervention for older adults using daily self-monitoring of body weight, step count, fruit/vegetable intake and water consumption. Forty weight-reduced (mean weight lost = 6.7 ± 0.6 kg; BMI 29.2 ± 1.1 kg/m2) individuals aged 63 ± 1 yrs, who had previously participated in a 12-week randomized controlled weight loss intervention trial, were instructed to record daily body weight (Weight), step count (Exercise), and fruit/vegetable intake (Vegetable). Experimental group (WEV+) participants were also instructed to consume 16 floz of water before each main meal (i.e., three times daily), and to record daily water intake. Outcome measures included weight change, diet/physical activity behaviors, theoretical constructs related to health behaviors, and other clinical measures. Statistical analyses included growth curve analyses and repeated measures ANOVA. Over 12 months, there was a linear decline in weight (β = −0.32, P < 0.001) and a quadratic trend (β = 0.02, P < 0.01) over time, but no group difference (β = −0.23, P = 0.08). Analysis of the 365 days of self-reported body weight for each participant determined that weight loss was greater over the study period in WEV+ than WEV, corresponding to weight changes of −0.67 kg and 1.00 kg respectively, and an 87% greater weight loss (β = −0.01, P < 0.01). Overall compliance to daily tracking was 76 ± 5%. Daily self-monitoring of weight, physical activity, and fruit/vegetable consumption is a feasible and effective approach for maintaining weight loss for 12 months, and daily self-monitoring of increased water consumption may provide additional WTLM benefits.
PMCID: PMC3378982  PMID: 22709772
Weight Loss Maintenance; Water; Self-Regulation; Physical Activity; Fruits and Vegetables
25.  Reducing Diabetes Risk in American Indian Women 
American Indians experience high rates of type 2 diabetes. The impact of low-intensity interventions on diabetes risk among young American Indian women is unknown.
Randomized controlled trial
Community-based; participants were 200 young urban American Indian women who were block-randomized on fasting blood glucose (FBG) into intervention and control groups. Inclusion criteria included self-reported identity, aged 18–40 years, not pregnant, willingness to stay in urban area for 2 years, and not having type 2 diabetes. Measures were taken at baseline, 6, 12, and 18 months. Data were gathered 2002–2006 and analyzed 2006–2007.
Five discussion group sessions (one meeting per month for five months) were held focusing on healthful eating, physical activity, goal-setting, and social support..
Main Outcome Measures
Primary outcomes included dietary fat and vegetable consumption and self-reported physical activity. Secondary outcomes included cardiorespiratory fitness, insulin sensitivity, blood pressure, lipid profiles, percent body fat, BMI, intake of fruit, total sugar and sweetened beverages, FBG, and television viewing.
Mean vegetable and fruit intake increased significantly more in the intervention group than in the control group over time (group by visit interaction, p=0.02 and p=0.002, respectively). Both groups had significant increases in percent body fat and decreases in waist circumference, insulin sensitivity, blood cholesterol, LDL, television viewing, and total intakes of energy, saturated fat, sugar, and sweetened beverages.
A culturally influenced, low-intensity lifestyle intervention can improve self-reported intakes of vegetables and fruit over 18 months in young, urban American Indian women.
PMCID: PMC2275812  PMID: 18312806

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