As shown in , the samples from the two sites differed in a number of demographic characteristics. There were more Hispanic people in LAC, while SL had a larger African American population and a slightly older demographic. The reported mean daily intake of calories from cookies, candy, salty snacks, soda, and alcohol, weighted to be representative of the underlying population, was 438 in LAC and 617 in SL, with a 150- to 200-calorie difference between men and women. Excluding alcohol reduced the amount by 90 calories for men (more in SL, less in LAC), but only by 25 calories for women. This level of calorie consumption was 1.61 times the recommended intake of discretionary calories from the Dietary Guidelines in LAC (taking into account gender, age, and physical activity) and 2.20 times the recommended intake in SL.
Characteristics of participants in a study of men and women in Los Angeles County and Southern Louisiana, 2004–2005
In LAC, the mean number of fruit/vegetable servings per day was 4.5, or 10% lower than the 5 A Day target; it was 20% lower than the target in SL. While the majority of people did not achieve the 5 A Day target, most missed by a relatively small amount (i.e., median consumption was four servings, or 20% below target). While the majority of people exceeded discretionary calories, most exceeded the recommendation by a larger margin (i.e., the median was 40% higher than the target).
shows the breakdown of calories consumed from candy, cookies, salty snacks, soda, and alcohol stratified by the key sociodemographic variables. People with lower income and education, men, and residents in SL consumed substantially more calories from these sources (p>0.01). Alcohol comprised a small portion of the calories consumed (14% for men and 6% for women, p<0.01). African Americans had the highest intake of calories from these sources overall (692 vs. 496 for white and 483 for Hispanic people, p<0.01) and in every category except alcohol. The total number of calories consumed from these sources for Hispanic people (483) was similar to non-Hispanic white people (496), but with fewer calories from alcohol and salty snacks and more calories from sodas. The sample sizes for other ethnic groups were too small to make detailed comparisons and are not shown, although people of Asian descent had the lowest consumption levels overall (i.e., 302 discretionary calories, including alcohol).
Estimated number of calories consumed in the past 24 hours from salty snacks, cookies, candy, soda, and alcohol, by sociodemographic group, in a study of men and women in Southern Louisiana and Los Angeles County, 2004–2005
shows consumption of fruit and vegetables by race/ethnicity and sociodemographic characteristics. In contrast with calories from candy, cookies, salty snacks, and soda, there were no significant differences in fruit and vegetable consumption by income group, men vs. women, or between non-Hispanic white and African American populations. Hispanic people had a higher consumption than non-Hispanic white people (p=0.03). We also found significant differences by educational status (p<0.01) and location (p<0.01).
Estimated number of daily calories consumed from fruit and vegetables, by sociodemographic group, in a study of men and women in Southern Louisiana and Los Angeles County, 2004–2005
stratifies consumption of calories from cookies, candy, salty snacks, soda, and alcohol by whether or not people consume fewer than five fruit and vegetables a day. The mean estimated calories from fruit and vegetables for those two groups were significantly different: 118 for those consuming fewer than five a day vs. 329 for those consuming at least five a day (p<0.01). However, there was no statistically significant difference between these two groups in terms of calories consumed from cookies, candy, salty snacks, soda, and alcohol. Thus, the increased calories from eating more fruit and vegetables was not offset by a similar reduction in calories from candy, cookies, salty snacks, and soda, let alone a larger reduction that would reduce weight in a healthful manner.
Figure 3. Estimated calories from salty snacks, cookies, soda, alcohol, fruit, and vegetables comparing those who consume ≥5 and <5 servings of fruit and vegetables daily, in a study of men and women in Southern Louisiana and Los Angeles County, (more ...)
Because differences in sociodemographic composition could confound results, we tested associations using multivariate regression (). The first column corresponds to the results for calories from cookies, candy, salty snacks, and soda, including alcoholic beverages; the second column excludes alcoholic beverages. Our main interest was determining whether there was any trade-off between calories that are mostly discretionary and fruit/vegetable consumption at the population level. For example, in the first row, first column of , –17 means that an extra serving of fruit was associated with a reduction of 17 calories from snacks, soda, and alcohol. The standard error (SE) (in this case, SE=6) means that this figure is statistically significant at p<0.01. The second column shows the same effect, but omits alcohol. In this case, an additional serving of fruit was associated with a statistically significant reduction of 16 calories from candy, cookies, salty snacks, and soda (95% confidence interval 5, 28), but this small reduction was much less than a serving of fruit would add (e.g., a medium apple is 72 calories). There was no evidence of any calorie offset from more vegetable consumption in these sources of discretionary calories.
Predictors of total and excess discretionary calorie consumption from snacks, soda, and alcohol, in a study of men and women in Los Angeles County and Southern Louisiana, 2004–2005a
As shown in , people in SL consumed a mean of 114 more calories from candy, cookies, salty snacks, alcohol, and soda than people in LAC (p<0.001). If alcohol is excluded, the difference drops to 99 calories. Women consumed significantly fewer of these calories than men; however, after taking into account their lower energy needs, they consumed 26% more calories than recommended for discretionary calories (without alcohol). African American people consumed a mean of 112 more calories from candy, cookies, salty snacks, and soda than their non-Hispanic white counterparts. College education and high income were powerful predictors of lower total and relative intake of calories from these sources. Age was a highly significant predictor of reduced total intake of candy, cookies, salty snacks, and soda, but because of different energy needs, the ratio of actual to recommended intake was no different for older than for younger respondents. Food stamp participation had no statistically significant effect on intake.
We also examined whether there was an interaction between the number of servings of fruit/vegetables and race/ethnicity and income to determine whether potential offsets depended on resources or ethnic group. Not one of the interactions of race/ethnicity with fruit or vegetables was significant, suggesting that at least there were no large differences between these groups in how the consumption of fruit/vegetables related to consumption of calories from candy, cookies, salty snacks, and soda (data not shown).
The relative consumption of candy, cookies, salty snacks, and soda was generally not affected in the sensitivity analysis using lower levels of calories per serving, although with lower levels, the difference in consumption between African American and other populations was no longer statistically significant at p<0.05. With lower estimates of calories per serving, the mean consumption was 30% higher than guidelines in LAC and 84% higher than guidelines in SL, down from 61% and 129%, respectively, in the baseline analysis reported in . Arguably, the more likely situation was that people underreported consumption and possibly overstated physical activity. We did not conduct a sensitivity analysis for this scenario, but it would only strengthen our findings about the disconcerting gap between consumption and recommended discretionary calories.