Metabolic profile before and after short-term overfeeding with a high-fat diet: a comparison between South Asian and white men

Abstract

For the same BMI, South Asians have a higher body fat percentage and an adverse metabolic profile compared with whites. The objective of the present study was to determine the metabolic profiles of South Asian and white men matched for body fat percentage in response to short-term overfeeding with a high-fat diet. A total of ten healthy non-diabetic South Asian men matched for body fat percentage with ten white men were included in the study. A weight-maintenance diet (containing 30 % fat, 55 % carbohydrate and 15 % protein) was provided for 3 d followed by 4 d of overfeeding (150 % of energy requirement) with a high-fat diet (60 % fat, 25 % carbohydrate and 15 % protein). Before and after the overfeeding period, plasma glucose, insulin, TAG, NEFA, total cholesterol and HDL-cholesterol concentrations were determined. Glucose clearance was calculated using a 2 h oral glucose tolerance test. The results revealed that in South Asian and white men, respectively, overfeeding with a high-fat diet decreased plasma TAG concentrations by 0·4 (SD 0·6) and 0·4 (SD 0·5) mmol/l (P diet ¼ 0·008; P ethnicity ¼ 0·24), increased HDL-cholesterol concentrations by 0·12 (SD 0·1) and 0·14 (SD 0·2) mmol/l (P diet ¼ 0·001; P ethnicity ¼ 0·06) and decreased glucose clearance by 48·8 (SD 53·5) and 37·2 (SD 34·2) ml/min per m 2 body surface (P diet ¼ 0·004;There was a significant interaction between diet and ethnicity with regard to the changes in total and LDL-cholesterol concentrations (P¼ 0·01 and 0·007, respectively), which trended towards a larger increase in South Asian subjects than in white subjects. Despite a similar body fat percentage, short-term overfeeding with a high-fat diet had more adverse effects on the lipid profile of South Asians than on that of whites.

A Single Day of Excessive Dietary Fat Intake Reduces Whole-Body Insulin Sensitivity: The Metabolic Consequence of Binge Eating

“…In the present study, we observed a reduction in insulin sensitivity but no change in fasting TG. This finding is in line with previous short-term overfeeding studies, which have observed impairments in glycemic control/reductions in insulin sensitivity alongside unchanged or even reduced fasting TG concentrations [ 24 , 25 , 28 ]. We did, however, observe a significant trial × time interaction for plasma TG across the 2-h OGTT, which appears to be due to a more dynamic/temporal postprandial response to glucose ingestion after overfeeding.…”

“…Short-term (4–14 days) adherence to a high-fat, high-energy diet has previously been reported to impair glycemic control and reduce insulin sensitivity in healthy individuals [ 23 , 24 , 25 , 27 , 28 ]. The findings we report here from our pilot study build upon this work and suggest that a single day of high-fat, high-energy food consumption impairs whole-body insulin sensitivity; evidenced by a significant (28%) reduction in whole-body insulin sensitivity as calculated by Matsuda ISI.…”

“…Results from short-term (4–14 days), high-fat overfeeding interventions report impaired glycemic control [ 23 , 24 , 25 ] and decreased hepatic [ 26 ] and whole-body insulin sensitivity [ 27 , 28 ] despite unchanged or reduced plasma NEFA concentrations. Although these studies demonstrate that impairments in glycemic control occur after several days or weeks of consistent overconsumption, this model may not reflect the dietary practices of those who binge eat and consume a severe energy excess within a matter of hours.…”

Molecular adaptation in adipose tissue in response to overfeeding with a high-fat diet under sedentary conditions in South Asian and Caucasian men

“…This was supported by our data from a similar study as presented here (28) that an extended meal consumption due to overfeeding prolonged the postprandial state and prolonged high insulin levels, which in turn favours fat storage rather than oxidation. Previous studies by us (20) and others (29,30) have shown higher insulin levels as a response to overfeeding. Moreover, Schmidt et al (31) reported a decrease in postabsorptive 24-h fat oxidation following 3 d of overfeeding in obesity-resistant subjects but not changed in obesity-prone subjects (presumably due to a higher NEFA level from the enlarged FM).…”

“…Any additional intake from those prescribed foods was recorded. All unfinished foods were collected and returned to the university to calculate actual energy intake as described previously (19,20) .…”