Less carbohydrate improves lipid profile

A carbohydrate-restricted diet may be more effective than a reduced fat intake in modestly improving the lipid profile. Physicians should counsel patients to adopt a diet they can stick to, rather than emphasizing on rapid weight loss.Researchers from the Duke University Medical Centre in Durham, North Carolina, randomly assigned 60 obese but otherwise healthy individuals with high lipid levels to a conventional diet that reduced calorie intake by 500 to 1000 calories per day, with less than 30 percent of calories from fat. The other 60 subjects were assigned to a diet of less than 20 grams of carbohydrate daily plus nutritional supplements.The 45 subjects in the low-carbohydrate group who completed the 6-month study lost an average of 12.9 per cent of their body weight. In the low-fat group, 34 completed the study, and their weight loss averaged 6.7 per cent.

The average level of LDL cholesterol, the bad cholesterol, decreased more with restricted carbohydrates. However, 13 of 44 (30%) had 10 per cent or higher increases in LDL, compared with 5 of 31 (16%) among those on the conventional weight-reduction diet. HDL cholesterol, the good cholesterol, increased more in the low-carbohydrate group.In another study, researchers at Philadelphia Veterans Affairs Medical Centre enrolled 132 severely obese subjects, among whom 64 were placed on a diet with carbohydrate restriction and 68 on a conventional diet. After 1 year, 20 in the low-carbohydrate group and 25 in the low-fat group had dropped out. Those in the low-carbohydrate group lost weight faster, but by study end, weight loss did not differ significantly between the two groups. Triglyceride levels decreased more in the low-carbohydrate group in the Philadelphia trial, and HDL cholesterol levels decreased less. Among the 54 subjects with diabetes, glucose levels declined significantly more in the low-carbohydrate group. In both studies, overall calorie intake decreased more in the low-carbohydrate diet, but the difference was not statistically significant.

Overweight patients can be encouraged to experiment with various methods for weight control, including reduced carbohydrate diets as long as they take healthy sources of fat & protein and incorporate regular physical activity.

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