|Nutrition Evidence Library|
Nickols-Richardson SM, Coleman MD, Volpe JJ, Hosig KW. 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. J Am Diet Assoc 2005; 105: 1433-1437.
PubMed ID: 16129086
Randomized Clinical Trial
A - Click here for explanation of classification scheme.
Research Design and Implementation Rating:
POSITIVE: See Research Design and Implementation Criteria Checklist below.
To examine the effects of a low-carbohydrate/high-protein diet with a high-carbohydrate/low-fat diet on self-reported scores of hunger and cognitive eating restraint in overweight premenopausal women during a 6-week dietary intervention designed for weight loss.
Overweight, premenopausal women, aged 32 - 45 years.
Excluded if BMI < 25 or > 40, body weight loss of > 5 kg in previous year, self-reported menstrual cycle length of < 21 or > 35 days or disruption of menstruation during the past year, currently pregnant or lactating, physical activity of > 7 hours per week, current cigarette smoking, metabolic or endocrine diseases or disorders, and use of medications affecting metabolic or endocrine function.
Description of Study Protocol:
Randomized Clinical Trial.
Blinding used (if applicable)
Intervention (if applicable)
Subjects consumed either low-carbohydrate/high-protein or high-carbohydrate/low-fat diet for 6 weeks.
Data are reported for 12 women in low-carbohydrate group and 11 in high-carbohydrate group due to incomplete dietary recall data. A t test was conducted to compare mean BMI at baseline to ensure no significant difference in BMI after randomization of women to diet groups. Repeated measures ANCOVA were conducted to detect significant group x time interactions in body weight, BMI, hunger, cognitive eating restraint, and dietary intake across time.
Data Collection Summary:
Timing of Measurements
Fasting body weight and Eating Inventory completed at baseline, weeks 1 - 4 and week 6.
Description of Actual Data Sample:
Initial N: 28 women
Attrition (final N): 28 women, although some dietary recalls removed for being incomplete. Low carbohydrate (n=13), high-carbohydrate (n=15)
Age: Low-carbohydrate: mean age 38.8 +/- 6.2 years, high-carbohydrate: mean age 40.1 +/- 6.3 years
Ethnicity: Not mentioned
Other relevant demographics:
Anthropometrics: Age, height, body weight, BMI and energy intake did not statistically differ between groups at baseline.
Summary of Results:
All women experienced a reduction in body weight (P < 0.01) but relative body weight loss was greater in the low-carbohydrate/high-protein vs high-carbohydrate/low-fat group at week 6 (5.7% vs 3.3%, P < 0.05).
Based on Eating Inventory scores, self-rated hunger scores decreased (P < 0.03) in the low-carbohydrate/high-protein group but not the high-carbohydrate/low-fat group from baseline to week 6.
In both groups, self-rated cognitive eating restraint increased (P < 0.01) from baseline to week 1 and remained constant to week 6.
Estimated average daily intake did not significantly differ between groups at any time point.
A low-carbohydrate/high-protein diet intervention seems to be effective for body weight reduction over a 6-week period, as does a high-carbohydrate/low-fat diet. Overweight premenopausal women complying with a low-carbohydrate/high-protein diet may lose proportionately more body weight over a short-term period. Maintenance of body weight loss facilitated by a low-carbohydrate/high-protein diet must be further evaluated and compared with other weight loss diets with varied macronutrient compositions, particularly in relation to hunger and cognitive eating restraint ratings. Subjects complying with the low-carbohydrate/high-protein diet reported less hunger but similar cognitive eating restraint compared with women following high-carbohydrate diet. The impact of hunger and cognitive eating restraint on compliance with dietary interventions for body weight loss and continued weight-loss maintenance must be considered and included in weight loss programs.
Removal of incomplete records leaves small sample size. Recruitment not defined.
Copyright American Dietetic Association (ADA).