Results
Annual Trends in Obesity and Overweight Prevalence by Immigrant Status and Educational Attainment, 1976 and 1991–2008
The obesity prevalence for the total US adult population aged ≥18 tripled from 8.7% in 1976 to 27.4% in 2008. The overweight prevalence for all US adults increased from 36.9% in 1976 to 62.0% in 2008. In 2008, 59 million US adults were obese and 134 million overweight. This represented an absolute increase of 47 million obese and 80 million overweight adults since 1976.
During 1991–2008, the obesity prevalence for US-born adults increased from 13.9 to 28.7%, whereas the prevalence for immigrants increased from 9.5 to 20.7% (Fig. 1). The average annual rates of increase for the two groups were 4.5% and 4.6%, respectively. During 1991–2008, increases in overweight prevalence were equally marked among both US-born and immigrant adults, with the prevalence for the US-born rising from 45.7 to 62.7%, while that for immigrants rising from 39.6 to 58.4%. Immigrant differentials in BMI increased over time. The mean BMI for the US-born increased from 25.24 in 1991 to 27.75 in 2008, while for immigrants it increased from 24.55 to 26.56 (Fig. 1).
Figure 1.
Trends in Obesity and Overweight Prevalence (%) among US Adults by Immigrant Status and Education, 1976–2008
Annual trends by educational attainment show persistent disparities in obesity and overweight prevalence and BMI (Fig. 1). Educational gradients were more consistent and pronounced in 1976 and the 1990s than during the first decade of the 2000s. The rate of increase in obesity and overweight was greater for those with 12, 13–15 and ≥16 years of education than for those with 0–8 and 9–11 years of education. During 1991–2008, the average annual rates of increase in obesity for the 5 (low to high) educational groups were 2.58, 3.63, 4.75, 5.54, and 5.05%, respectively. The corresponding rates of increase in overweight were 1.36, 1.90, 2.32, 2.90, and 2.25%.
Socioeconomic Profiles of Ethnic-immigrant Groups, 2003–2008
The immigrant groups varied substantially in their socioeconomic characteristics (Fig. 2). Overall, immigrants had nearly twice the poverty levels of the US-born. They were also twice as likely to be without a high school diploma as the US-born. Socioeconomic achievement levels increased with increasing duration of residence in the US. During 2003–2008, less than 6% of Mexican immigrants were college graduates, compared with 67% of recent Asian Indian immigrants. Less than 9% of Mexican immigrants were employed in professional and managerial occupations, as compared with 52% of recent Asian Indian immigrants and 53% of US-born Chinese. Poverty rates varied from a low of 5% for long-term Filipino immigrants to a high of 33% for recent Mexican immigrants.
Figure 2.
Selected Socioeconomic Characteristics (%) of 30 Ethnic-Immigrant Groups, US Adults Aged 18 years and Older, 2003–2008
Ethnic-immigrant and Socioeconomic Disparities in Obesity and Overweight Prevalence, 1976, 1992–1995, and 2003–2008
Table 1 shows increases in obesity prevalence between 1992–1995 and 2003–2008 for detailed ethnic-immigrant and socioeconomic groups. Regardless of ethnicity, all immigrant groups experienced a substantial increase in prevalence, with the increase being greater among the US-born population and longer-term immigrants.
Tables 1 and 2 show considerable disparities in obesity and overweight prevalence by immigrant status and selected socioeconomic factors. The observed obesity prevalence in 2003–2008 ranged from 2.3% for recent Chinese immigrants to 30.6% or higher for American Indians, US-born blacks, Mexicans, and Puerto Ricans, and long-term Mexican and Puerto Rican immigrants (Table 1). The overweight prevalence in 2003–2008 ranged from 19.8% for recent Chinese immigrants to 70% or higher for American Indians, US-born blacks and Mexicans, and long-term Mexican and Puerto Rican immigrants (Table 2). Mean BMI in 2003–2008 varied from a low of 22.6 for recent Chinese immigrants to a high for 28.9 for US-born blacks and American Indians, and 28.6 for US-born Mexicans (Table 3). The summary index of disparity showed similar ethnic-immigrant disparities in obesity and overweight prevalence in 1992–1995 and 2003–2008.
The odds and prevalence of obesity and overweight, even after adjusting for sociodemographic factors, increased with increasing duration in the US (Tables 1, 2). The obesity gradients by length of immigration were steeper in 2003–2008 than in 1992–1995. Compared with the US-born, immigrants who had lived in the US for <1 year or ≥15 years had 73 or 34% lower odds of obesity in 2003–2008 and 59 or 28% lower odds of obesity in 1992–1995, respectively (Table 1). Immigrants who had lived in the US for <1 year or ≥15 years had 57 or 18% lower odds of overweight than the US-born in 2003–2008 (Table 2). During 1992–2008, the disparity indices suggest a slight increase in obesity differentials between US-born and immigrants of various durations.
Compared with US-born whites, the odds of obesity were 59 and 25% lower for recent and long-term white immigrants, 36% lower for recent black immigrants, 55–92% lower for US- and foreign-born Chinese, Asian Indians, and Filipino immigrants, 34–52% lower for recent Mexican and Central/South American immigrants, respectively. However, US-born blacks, American Indians, Mexicans, and Puerto Ricans, and long-term Puerto Rican immigrants had 60, 81, 64, 32, and 23% higher odds of obesity, respectively than US-born whites (Table 1). Compared with Chinese immigrants, US-born blacks, Mexicans, Puerto Ricans, and Central/South Americans, and American Indians had 14–19 times higher odds of obesity, whereas white, black, Mexican, Cuban, and Central/South American immigrants had 4–13 times higher odds of obesity. Compared with Chinese immigrants, all other ethnic-immigrant groups had 3–10 times higher odds of overweight (Table 4).
Socioeconomic gradients in obesity, although substantial in each period, were less pronounced in 2003–2008 than in 1992–1995 and 1976. The summary indices also indicate decreasing educational disparities over time. Between 1976 and 2008, obesity prevalence doubled for those with <9 years of education, while it increased 4–5 fold for those with a college education. Those with <9 years of education had 152% higher adjusted odds of obesity in 1976, 90% higher odds in 1992–1995, and 63% higher odds in 2003–2008 than those with a college degree. In terms of continuous education, each additional year of education was associated with 11% lower odds of obesity (OR = 0.89; 95% CI = 0.89–0.90) and 7% lower odds of overweight (OR = 0.93; 95% CI = 0.93–0.94) in 1976, 8% lower odds of obesity (OR = 0.92; 95% CI = 0.92–0.92) and 6% lower odds of overweight (OR = 0.94; 95% CI = 0.94–0.94) in 1992–1995, and 6% lower odds of obesity and overweight (OR = 0.94; 95% CI = 0.94–0.95) in 2003–2008. Each additional year of education was associated with a 0.17 point decrease in BMI in 2003–2008, the effect being significantly lower than the 0.19 point decrease in BMI in 1992–1995 (P < .001).
Income gradients were steeper in 1992–1995 than in 2003–2006, with income disparities in prevalence, as measured by the summary indices, diminishing over time. During 2003–2006, those with family income <$10,000 had 44% higher odds of obesity than those with income ≥$65,000; the roughly comparable odds in 1992–1995 were 62% higher for those with family income <$7,000 than for those with income ≥$50,000. A $5,000 increase in family income was associated with 7% (OR = 0.93; 95% CI = 0.93–0.93) and 4% (OR = 0.96; 95% CI = 0.96–0.96) lower odds of obesity and overweight, respectively in 1992–1995; in 2003–2006, the corresponding odds ratios were smaller: 0.97 (95% CI = 0.97–0.98) for obesity and 0.99 (95% CI = 0.98–0.99) for overweight. A $5,000 increase in family income was associated with a 0.08 point decrease in BMI in 2003–2006, the effect being significantly lower than the 0.14 point decrease in BMI in 1992–1995 (P < .001).
The obesity prevalence for individuals in sales occupations quadrupled and for those in other occupations tripled between 1976 and 2003–2008. In 2003–2008, after adjusting for education, income, and other demographic factors, service workers and laborers had 7 and 21% higher odds of obesity than those employed in professional/managerial occupations. Although observed occupational inequalities in obesity were substantial, most of the occupational effects were accounted for by education and income differences.
After adjusting for ethnicity and socioeconomic factors, physical inactivity was associated with 54% higher odds of obesity (OR = 1.54; 95% CI = 1.46–1.62) and 36% higher odds of overweight (OR = 1.36; 95% CI = 1.30–1.42) in 2003–2008 (data from the full model not shown).
J Community Health. 2011;36(1):94-110. © 2011 Springer
Springer Science+Business Media
Cite this: Dramatic Increases in Obesity and Overweight Prevalence and Body Mass Index among Ethnic-immigrant and Social Class Groups in the United States, 1976–2008 - Medscape - Feb 01, 2011.


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