Conclusions Large r and omized controlled trials of at least 6 months duration with carbohydrate restriction appear superior in improving lipid markers when compared with low-fat diets .
Context Carbohydrate-restricted diets may increase low-density lipoprotein cholesterol and thereby cardiovascular risk .
Objective A systematic review and meta-analyses were conducted to compare the effects of very low , low , and moderate carbohydrate , higher fat diets versus high-carbohydrate , low-fat diets on low-density lipoprotein cholesterol and other lipid markers in overweight/obese adults .
A low-carbohydrate as compared with a low-fat diet in severe obesity.
BACKGROUND The effects of a carbohydrate-restricted diet on weight loss and risk factors for atherosclerosis have been incompletely assessed . METHODS We r and omly assigned 132 severely obese subjects ( including 77 blacks and 23 women ) with a mean body-mass index of 43 and a high prevalence of diabetes ( 39 percent ) or the metabolic syndrome ( 43 percent ) to a carbohydrate-restricted ( low-carbohydrate ) diet or  a calorie- and fat-restricted ( low-fat ) diet . RESULTS Seventy-nine subjects completed the six-month study . An analysis including all subjects , with the last observation carried forward for those who dropped out , showed that subjects on the low-carbohydrate diet lost more weight than those on the low-fat diet ( mean [ + /-SD ] , -5.8+/-8.6 kg vs. -1.9+/-4.2 kg ; P=0.002 ) and had greater decreases in triglyceride levels ( mean , -20+/-43 percent vs. -4+/-31 percent ; P=0.001 ) , irrespective of the use or nonuse of hypoglycemic or lipid-lowering medications . Insulin sensitivity , measured only in subjects without diabetes , also improved more among subjects on the low-carbohydrate diet ( 6+/-9 percent vs. -3+/-8 percent , P=0.01 ) . The amount of weight lost ( P<0.001 ) and assignment to the low-carbohydrate diet ( P=0.01 ) were independent predictors of improvement in triglyceride levels and insulin sensitivity . CONCLUSIONS Severely obese subjects with a high prevalence of diabetes or the metabolic syndrome lost more weight during six months on a carbohydrate-restricted diet than on a calorie- and fat-restricted diet , with a relative improvement in insulin sensitivity and triglyceride levels , even after adjustment for the amount of weight lost . This finding should be interpreted with caution , given the small magnitude of overall and between-group differences in weight loss in these markedly obese subjects and the short duration of the study . Future studies evaluating long-term cardiovascular outcomes are needed before a carbohydrate-restricted diet can be endorsed
Conclusions Large r and omized controlled trials of at least 6 months duration with carbohydrate restriction appear superior in improving lipid markers when compared with low-fat diets .
Context Carbohydrate-restricted diets may increase low-density lipoprotein cholesterol and thereby cardiovascular risk .
Objective A systematic review and meta-analyses were conducted to compare the effects of very low , low , and moderate carbohydrate , higher fat diets versus high-carbohydrate , low-fat diets on low-density lipoprotein cholesterol and other lipid markers in overweight/obese adults .