This study documents a rapid increase in obesity and diabetes within a 2-year time period among adults in New York City, larger than that observed in the United States overall. The 17% increase in prevalence of self-reported obesity that occurred from 2002 to 2004 corresponds to an additional 173,500 obese adults, and the 17% increase in diabetes prevalence, corresponds to approximately 73,600 additional adults reporting a diagnosis of diabetes. As of 2004, nearly 1 in 4 adults in New York City were obese, and 1 in 10 had diagnosed diabetes. The rapid rise of obesity in the city has brought prevalence to a level comparable to the national average.
The increase in obesity among adult New Yorkers corresponds to an average weight gain of 2 pounds per person between 2002 and 2004, indicating a total citywide weight gain of more than 10 million pounds, with the largest increases occurring at the higher end of the weight spectrum (i.e., 75th percentile). Between 2002 and 2004, the change in obesity was different in New York City than in the United States. For instance, obesity increased among both whites (20%, P
< .05) and Hispanics (14%, P
< .05), but national increases were significant only among whites (7%, P
< .05). Thus, the 2-year rate of increase in obesity was higher than the national increase in the two largest racial/ethnic subpopulations that together comprise nearly two-thirds of the total population of New York City: 38% of adults are white, 23% are black, 25% are Hispanic, and 14% are Asian/Pacific Islander or of another racial/ethnic group (19
). The increase in obesity was also considerable among older New Yorkers (28%), whereas estimates of obesity among older adults in the United States overall were stable over time. Finally, there was a dramatic (33%) increase in the prevalence of obesity among foreign-born New Yorkers from 2002 to 2004.
Although some characteristics of the New York City population, such as its racial/ethnic profile and its higher level of poverty, suggest that rates of obesity should be higher than the national average, in 2004 its obesity rate was comparable to national levels, not higher. Although we documented an income-associated gradient for obesity among adult New Yorkers as well as higher rates among Hispanic and black residents than rates among whites, the race-specific obesity levels among whites and blacks in New York City were comparable to national levels. Because of differences in methods of measuring income in the CHS and BRFSS, a direct comparison of obesity levels by poverty level was not possible for this study. Still, the obesity estimates for New York City compared with those for the United States overall, despite the high proportions of black, Hispanic, and poor adults in the city, suggest that other factors have a protective effect on local obesity levels.
One factor that may attenuate obesity levels in New York City is nativity. Research has demonstrated an inverse association between foreign-born status and obesity (16
), and the lower prevalence of obesity that we observed among foreign-born adults in the city is consistent with this finding. In New York City, foreign-born adults comprise 44% of the adult population (19
), compared with only 13% of the adult population of the United States (21
), and the significantly lower obesity levels among foreign-born residents influenced race-specific and overall obesity levels. We were unable to make a direct comparison of obesity levels by country of birth in this study because BRFSS does not collect data on nativity for foreign-born U.S. residents.
Another possible explanation for why the 2004 prevalence of obesity in New York City is lower than its sociodemographic makeup might suggest is urban design. With neighborhoods that are limited to defined geographic boundaries, largely completed by the 1950s and 1960s, New York City is a generally walkable environment, characterized by mixed land use, and connected both internally and externally by rail transportation systems (17
), making it relatively small, with both retail and residential destinations easily accessible by public transportation and by foot. However, given the stability of the city's built environment, the rapid rise in obesity suggests that other factors are driving the increase over time. Because the urban design of New York City may be considerably different from that of other parts of the country, particularly in the southern and midwestern United States, future research should investigate the impact of the built environment on obesity and diabetes in the context of other factors, including race, ethnicity, poverty, and sociocultural factors that affect obesity and diabetes.
The prevalence of diabetes increased significantly in New York City from 2002 to 2004, whereas it remained constant nationally during that time. This increase was significant among men, older adults, whites, and those living in higher income neighborhoods. Increases were also significant among both U.S.-born and foreign-born adults, but were more marked among foreign-born adults (26% vs 15% increase in 2 years). These findings suggest that more adult New Yorkers, particularly those in the wealthier segments of the population, are developing diabetes. The higher 2004 prevalence may also reflect recent increases in diabetes screening in some subpopulations of the city.
In contrast to our findings on obesity, we found that the prevalence of diabetes in New York City surpassed the national prevalence in 2004 (9.5% vs 7.1%, P < .05). The higher prevalence largely reflects the high rates of this disease among poorer residents and among black and Hispanic adults, suggesting that fewer local protective factors may exist for diabetes than for obesity. Indeed, the prevalence of diabetes among Hispanic New Yorkers was higher than that of Hispanics in the United States overall (13.1% vs 9.8%, P < .05). Prevalence of the disease among people aged 65 or older was also higher than in the United States overall for that age group (23.2% vs 16.6%, P < .05).
In the future, the prevalence of obesity and diabetes in both New York City and in the United States will be affected by growth in the populations that experienced the largest increases in these conditions between 2002 and 2004, specifically older adults, Hispanics, and the foreign-born (34
). Adults aged 65 or older currently comprise about 12% of the population, both in New York City and in the United States (19
). This age group is projected to grow more rapidly than any other within the next several decades, partly because of the aging of the baby boom generation (34
). Similarly, Hispanics are expected to comprise 23% of the U.S. population by the year 2050, and immigration is projected as a primary driver of overall population growth (34
). Understanding and responding to the impact of these changes in the population groups of New York City and the United States will continue to require local and national data.
Limitations and strengths
Limitations of this analysis include those related to self-reported data. Specifically, because data from the CHS are self-reported, estimates of obesity are likely to be low; people typically overstate their height and understate their weight (35
). Similarly, our estimates of diabetes are likely to be low because not all adults with diabetes will recall their diabetes status during an interview and because diabetes is often undiagnosed; about 30% of adults with diabetes do not know they have it (36
). However, because the questions were identical in 2002 and 2004 and because these samples are highly comparable, underreporting is not expected to have varied between years and would thus not affect our analysis. Additional limitations of the study include its cross-sectional design, which limits our ability to assess temporality or track incident conditions. Institutionalized adults and those without telephones were not represented in the sampling frame, limiting the generalizability of our findings. In addition, bias may have been introduced as a result of perceived pressure to provide socially desirable answers; however, the anonymous nature of the survey may have limited this effect (22
). Because local and national data were collected with the same survey method, these limitations should not affect our comparisons. The large difference in the size of the BRFSS and CHS samples is an additional limitation because larger population samples, such as the BRFSS sample, are more likely to yield statistically significant results than smaller samples, such as the CHS. Therefore, all else being equal, the BRFSS would yield more statistically significant differences than the CHS. However, there were actually more statistically significant differences between years in New York City than in the United States. Finally, this trend analysis is limited to only 2 years of data. Additional research examining data from the CHS and BRFSS should be ongoing in the future to assess longer-term trends. On the other hand, the smaller CHS sample means less precise estimation of trends compared to BRFSS. Strengths of the CHS include representativeness because it is conducted in multiple languages and its data characterizes the adult New York City population.
From 2002 to 2004, an additional 173,500 adult New Yorkers became obese, and an additional 73,600 were diagnosed with diabetes. Increases in obesity and diabetes were largest among some of the most rapidly growing subgroups in New York City and the United States, suggesting that the health impact and burden to the health care system related to these conditions may accelerate in coming years. Differences in obesity and diabetes between New York City and the United States underscore the need for local data. Understanding trends is important for local programming and policy making. Without immediate action, both New York City and the United States as a whole will experience increasingly urgent and damaging epidemics.