Enhanced dietary fat clearance in postobese women

The objective of this study was to examine the postprandial response toan exogenous fat source in eight weight-stable postobese subjects (2–3years after gastric bypass) and eight matched control women, using a stableisotope, 13Coleate. After a high fat breakfast meal (1,062 cal, 67%fat), 13Coleate in triglyceride (TG)-rich lipoproteins(Sf >400 and Sf 20–400) andnonesterified fatty acids (NEFA), and 13C in breath CO2,were monitored over 8 h. There were no differences in resting energyexpenditure, thermic effect of food, carbohydrate/fat oxidation ratio, breath13CO2 enrichment, or fecal fat content betweenpostobese and control subjects. Postprandially, there was no difference inSf 20–400 TG or NEFA, but postobese subjects had lowerSf >400 incremental area under the curve (AUC)(−33%, P 400 TGreturned to fasting levels 4 h earlier in postobese subjects and was lower thanin control subjects at 4 and 6 h (P 400 and Sf 20–400) andnonesterified fatty acids (NEFA), and 13C in breath CO2,were monitored over 8 h. There were no differences in resting energyexpenditure, thermic effect of food, carbohydrate/fat oxidation ratio, breath13CO2 enrichment, or fecal fat content betweenpostobese and control subjects. Postprandially, there was no difference inSf 20–400 TG or NEFA, but postobese subjects had lowerSf >400 incremental area under the curve (AUC)(−33%, P 400 TGreturned to fasting levels 4 h earlier in postobese subjects and was lower thanin control subjects at 4 and 6 h (P 400 and Sf 20–400) by at for 30 and at for h R. H. J. The and in human Clin. Invest. Scholar). The was for and Sf 20–400 TG were by was by a and in fasting by a was to Miller M. S. and of of human by a Lipid Res. by was to as by and G. M. in and Chem. 1996; 42: Scholar). by after the were was a of body oxidation of dietary fatty J. Clin.Nutr. 42: Scholar). were for of 13C was by of of acid of in a body oxidation of dietary fatty J. Clin.Nutr. 42: Scholar). were to a mass for 13C In is with a The is defined to be and and of Scholar). The was with of of 13C was to the C. M. C. M. of to study triglyceride metabolism 1995; the at in breath was as a of 13C in breath was to T. Jr., 13C of and of in 13C of for breath J. Clin. Nutr. 13Coleate is the mass of is the 13Coleate P is 13C is the of the and is to for the uptake of the for the R.J. in Scholar). 13C was in >400 and Sf 20–400 were with The was and in and and TG by on using acid as were with and were were and and and were were under at a of than TG were at for 4 h. The and were by a was a in a body oxidation of dietary fatty J. Clin.Nutr. 42: Scholar). were in h. was for breath C. M. C. M. of to study triglyceride metabolism 1995; in of the three Sf 20–400 and was as of TG or in that were from postobese women on a and for fecal fat content by the acid acid is a and to fecal fat with a sensitivity of and of with the fecal fat a 1997; 92: Scholar). In the were by and with acid The was and the fatty and The normal is a 1997; 92: Scholar, M. P. A. J. B. R. The acid a 1994; Scholar, A. J. M. of 1997; Scholar). are as were by by repeated measures analysis of RM using analysis was with the or to the and the mean difference was fasting and was by was at P 400 the greatest differences the in the Sf >400 there was no mean >400 TG to earlier in 8 with significantly lower Sf >400 6 h (P 0.02). Sf >400 incremental was lower in h in control h in P 400 and but not with glucose not with ASP as with fasting >400 NEFA, and and Sf >400 TG and with postprandial of ASP and insulin to postprandial >400 20–400 and are for under the curve insulin and fasting for control and eight postobese in a and are for under the curve insulin and fasting for control and eight postobese divided as to obesity to of energy expenditure and fatty acid oxidation (4Astrup A. Dietary composition, substrate balances andbody fat in subjects with a predisposition to obesity.Int. J. Obes. Relat. Metab. Disord. 1993; 17: S32-S36Google Scholar, 5Astrup A. Buemann B. Christensen N.J. Toubro S. Failure to increase lipid oxidation inresponse to increasing dietary fat content in formerly obesewomen.Am. J. Physiol. 1994; 266: E592-E599Google Scholar, 6Franssila-Kallunki A. Rissanen A. Ekstrand A. Ollus A. Groop L. 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L. of the obese and 1994; Scholar). has to the obesity may be the of fatty acid The study suggest at in this may and may mechanism in the of the This from in the there was clearance TG from the of the postobese women as with the and 13Coleate in the postobese than in the control findings with fatty acid by in the with the control women. The subjects in postobese had gastric than before the weight had the normal and were weight for at 6 at of this The control subjects were to there were in body ratio, and the the difference the that the of one had a of obesity and gastric those of the other the of the the on fat be In and in not Metabolic of obesity J. Clin.Nutr. 1992; 55: Scholar, study of Scholar, for Scholar, rate after gastric 1987; Scholar), most of the of the On the other hand, after may from and of gastric 1994; Scholar, M. Harding M.J. Walsh of gastric after gastric Scholar). This after high with M. Harding after gastric J. Obes. 10: was of subjects had of and after the meal in this which to this and of gastric 1994; Scholar). the had normal fecal fat content and differences in fat for The is that over the of the study no of significant difference in energy expenditure the fatty acid was not in the postobese there was no difference in fasting TG the differences in clearance and of dietary be attributed to this and believe that is a There were differences in postprandial clearance of TG the but were not postprandial TG not the postprandial Sf >400 to fasting levels earlier in the postobese the control This was for the Sf >400 levels 4 h earlier in the postobese there was no in the the of TG is a suggest that of by may be increased and it has that increases after weight loss B. J. The of weight loss on the of in J. Scholar, of activity Clin.Invest. Scholar, in in J. Obes. 1995; Scholar). The the of the fatty acids that are from the which be or the or The with to the of dietary fatty the the postobese with the control was three in the postobese than control subjects. the 13Coleate was three in the control subjects with the with those by C. C. M. M. R. M. Metabolic of an in 1996; Scholar, C. C. M. D. J. P. M. of human obesity on of dietary and J. Clin.Nutr. 1998; their study of postprandial fatty acid metabolism in obese women weight women. the On the other hand, no differences in the metabolism of levels of insulin, and were in this insulin and ASP there was a lower fasting and in the postobese subjects with the control subjects. the glucose levels and of fatty acid in it is possible that lower levels to as is the in are not is of that the levels were lower in the postobese subjects than in the this to regain weight to In to fatty acid by in postobese subjects and the that an be in the of studies are to a This was by the of and Cianflone is from the of of