Background: The prevalence and correlates of obese individuals who are resistant to the development of the adiposity-associated cardiometabolic abnormalities and normal-weight individuals who display cardiometabolic risk factor clustering are not well known. Methods: The prevalence and correlates of combined body mass index (normal weight, Ͻ25.0; overweight, 25.0-29.9; and obese, Ն30.0 [calculated as weight in kilograms divided by height in meters squared]) and cardiometabolic groups (metabolically healthy, 0 or 1 cardiometabolic abnormalities; and metabolically abnormal, Ն2 cardiometabolic abnormalities) were assessed in a cross-sectional sample of 5440 participants of the National Health and Nutrition Examination Surveys 1999-2004. Cardiometabolic abnormalities included elevated blood pressure; elevated levels of triglycerides, fasting plasma glucose, and C-reactive protein; elevated homeostasis model assessment of insulin resistance value; and low high-density lipoprotein cholesterol level. Results: Among US adults 20 years and older, 23.5% (approximately 16.3 million adults) of normal-weight adults were metabolically abnormal, whereas 51.3% (approximately 35.9 million adults) of overweight adults and 31.7% (approximately 19.5 million adults) of obese adults were metabolically healthy. The independent correlates of clustering of cardiometabolic abnormalities among normal-weight individuals were older age, lower physical activity levels, and larger waist circumference. The independent correlates of 0 or 1 cardiometabolic abnormalities among overweight and obese individuals were younger age, non-Hispanic black race/ethnicity, higher physical activity levels, and smaller waist circumference. Conclusions: Among US adults, there is a high prevalence of clustering of cardiometabolic abnormalities among normal-weight individuals and a high prevalence of overweight and obese individuals who are metabolically healthy. Further study into the physiologic mechanisms underlying these different phenotypes and their impact on health is needed.

OBJECTIVE -To determine the association between serum 25-hydroxyvitamin D (25OHD) and diabetes risk and whether it varies by ethnicity. RESEARCH DESIGN AND METHODS -We performed an analysis of data from participants who attended the morning examination of the Third National Health and Nutrition Examination Survey (1988 -1994), a cross-sectional survey of a nationally representative sample of the U.S. population. Serum levels of 25OHD, which reflect vitamin D status, were available from 6,228 people (2,766 non-Hispanic whites, 1,736 non-Hispanic blacks, and 1,726 Mexican Americans) aged Ն20 years with fasting and/or 2-h plasma glucose and serum insulin measurements.RESULTS -Adjusting for sex, age, BMI, leisure activity, and quarter of year, ethnicityspecific odds ratios (ORs) for diabetes (fasting glucose Ն7.0 mmol/l) varied inversely across quartiles of 25OHD in a dose-dependent pattern .60] for nonHispanic whites and 0.17 [0.08 -0.37] for Mexican Americans) in the highest vitamin D quartile (25OHD Ն81.0 nmol/l) compared with the lowest 25OHD (Յ43.9 nmol/l). This inverse association was not observed in non-Hispanic blacks. Homeostasis model assessment of insulin resistance (log e ) was inversely associated with serum 25OHD in Mexican Americans (P ϭ 0.0024) and non-Hispanic whites (P ϭ 0.058) but not non-Hispanic blacks (P ϭ 0.93), adjusting for confounders.CONCLUSIONS -These results show an inverse association between vitamin D status and diabetes, possibly involving insulin resistance, in non-Hispanic whites and Mexican Americans. The lack of an inverse association in non-Hispanic blacks may reflect decreased sensitivity to vitamin D and/or related hormones such as the parathyroid hormone. Diabetes Care 27:2813-2818, 2004T here is increasing evidence that vitamin D metabolism affects the risk of diabetes. Initial findings from animal studies showed that insulin released from the isolated perfused pancreas of the rat is lower in vitamin D-deficient animals than control animals (1), while pancreatic receptors for 1,25-dihydroxyvitamin D 3 in ␤-cells have been identified in a number of species (2). More recently, human studies have shown that vitamin D supplementation in infancy reduces the risk of type 1 diabetes during early adulthood (3).Vitamin D may also have a role in the development of type 2 diabetes. TaqI vitamin D receptor polymorphisms have been associated with an insulin secretion index among Bangladeshi Asians living in London, who have a high risk of type 2 diabetes (4). The BsmI polymorphism was associated with fasting glucose in inactive German men (5). In the Rancho Bernardo study (6) of older U.S. Caucasians, the ApaI polymorphism was associated with fasting plasma glucose and prevalence of glucose intolerance and the BsmI polymorphism with the homeostatis model assessment (HOMA) of insulin resistance.Given that a number of investigations have shown that vitamin D receptor polymorphisms are associated with various measures of glucose metabolism and diabetes risk, it seems reasonable to conclude t...

Background:The prevalence and correlates of obese individuals who are resistant to the development of the adiposity-associated cardiometabolic abnormalities and normal-weight individuals who display cardiometabolic risk factor clustering are not well known.