Perceived hunger is lower and weight loss is greater in overweight premenopausal women consuming a low-carbohydrate/high-protein vs high-carbohydrate/low-fat diet.

The impact of a low-carbohydrate/high-protein diet compared with a high-carbohydrate/low-fat diet on ratings of hunger and cognitive eating restraint were examined. Overweight premenopausal women consumed a low-carbohydrate/high-protein (n=13) or high-carbohydrate/low-fat diet (n=15) for 6 weeks. Fasting body weight (BW) was measured and the Eating Inventory was completed at baseline, weeks 1 to 4, and week 6. All women experienced a reduction in BW (P<.01), although relative BW loss was greater in the low-carbohydrate/high-protein vs high-carbohydrate/low-fat group at week 6 (P<.05). Based on Eating Inventory scores, self-rated hunger decreased (P<.03) in women in the low-carbohydrate/high-protein but not in the high-carbohydrate/low-fat group from baseline to week 6. In both groups, self-rated cognitive eating restraint increased (P<.01) from baseline to week 1 and remained constant to week 6. Both diet groups reported increased cognitive eating restraint, facilitating short-term weight loss; however, the decrease in hunger perception in the low-carbohydrate/high-protein group may have contributed to a greater percentage of BW loss.

Urinary ketones reflect serum ketone concentration but do not relate to weight loss in overweight premenopausal women following a low-carbohydrate/high-protein diet.

This study examined the effect of a low-carbohydrate/high-protein diet on serum and urine ketone body concentrations. Thirteen overweight premenopausal women aged 32 to 45 years consumed < or =20 g carbohydrate/day with liberal intakes of protein and fat for 2 weeks; thereafter, carbohydrate intake increased 5 g/week for 10 weeks. Women were weighed and provided fasting urine and blood samples to detect urinary ketones and quantify serum ketone concentrations, respectively, at baseline and weeks 1 to 4, 6, and 12. Women lost 8.3%+/-2.8% of initial body weight by week 12. Serum beta-hydroxybutyrate production was highest at week 1 and declined weekly, with all values higher than baseline (P <.05). Each week, serum beta-hydroxybutyrate was correlated with presence of urinary ketones (P <.05), but no relationship was found between weekly weight change and serum ketone production. Urinary ketones are detected in premenopausal women complying with a low-carbohydrate/high-protein diet and are associated with serum ketone concentration. However, serum ketones do not reflect weight loss.