Effects of weight loss on changes in insulin sensitivity and lipid concentrations in premenopausal African American and white women.
BACKGROUND
Few studies have tested the hypothesis that changes in disease risk factors are more closely associated with changes in visceral fat than with changes in other adipose tissue depots, particularly in subjects with different ethnic or racial backgrounds.


OBJECTIVE
We describe changes in triacylglycerol, total cholesterol, HDL cholesterol, LDL cholesterol, insulin sensitivity (S(i)), visceral fat, and subcutaneous abdominal adipose tissue (SAAT) with weight loss in premenopausal, overweight [body mass index (in kg/m(2)): 27-30], African American (n = 19) and white (n = 18) women.


METHODS
Assessments were performed before and after diet-induced weight loss to a BMI < 25. Body composition and body fat distribution were assessed with dual-energy X-ray absorptiometry and computed tomography, respectively; S(i) was assessed with an intravenous-glucose-tolerance test and minimal modeling.


RESULTS
White women lost significantly more visceral fat and less SAAT than did African American women despite similar weight losses (approximately 13 kg). Mixed-model analysis indicated significant effects of time (ie, weight loss) on S(i), triacylglycerol, HDL cholesterol, and LDL cholesterol and of race on triacylglycerol. Time x race interaction terms were not significant. After adjustment for either total body or visceral fat, time was not related to any outcome variable; however, race remained significantly related to triacylglycerol.


CONCLUSIONS
With weight loss, moderately overweight African American and white women experienced significant improvements in S(i) and lipids. The beneficial effects of weight loss did not differ with race and could not be attributed to a specific body fat depot. Lower triacylglycerol concentrations among African American women are independent of both obesity status and body fat distribution.
Gower
Barbara A
BA
University of Alabama at Birmingham, Department of Nutrition Sciences, 35294-3360, USA. bgower@uab.edu
Weinsier
Roland L
RL
Jordan
Julia M
JM
Hunter
Gary R
GR
Desmond
Reneé
R
D000005:Abdomen / Q000473:pathology; D000273:Adipose Tissue / Q000473:pathology; D000328:Adult; D001741:Black or African American; D044383:Black People; D005260:Female; D006801:Humans; D007328:Insulin / Q000502:physiology*; D008055:Lipids / Q000097:blood*; D008875:Middle Aged; D009765:Obesity / Q000097:blood / Q000208:ethnology / Q000473:pathology* / Q000503:physiopathology; D009994:Osmolar Concentration; D017697:Premenopause / Q000502:physiology*; D040521:Subcutaneous Tissue / Q000473:pathology; D014280:Triglycerides / Q000097:blood; D014781:Viscera / Q000473:pathology; D015431:Weight Loss; D044465:White People
D007328:Insulin; D008055:Lipids; D014280:Triglycerides