Abstract P167: The Long-term Effect of a Low-Carbohydrate Diet on Appetite Hormones: A Randomized Controlled Trial
The long-term effects of low-carbohydrate diets on hormones related to appetite are unclear.
We recruited a total of 148 study participants with a body mass index of 30 - 45 kg/m2 (Mean: 35.4 kg/m2) who were free of diabetes, cardiovascular diseases and kidney disease. The participants were randomly assigned to either a low-carbohydrate diet (<40 g/day; N=75) or a low fat (<30% energy from fat, <10% from saturated fat; N=73) diet. Two 24-hour dietary recalls were conducted at each clinic visit (0, 3, 6 and 12 months of the intervention). Participants met with a study dietitian weekly for the first month followed by group settings bi-weekly for 5 months then monthly for the subsequent 6 months. Each group was provided the same behavioral curriculum related to diet emphasizing portion control and eating habits. Total ghrelin and peptide YY were determined using radioimmunoassay methods.
Of the study participants, 60 in the low-fat group (81.1%) and 59 in the low-carbohydrate group (79.7%) completed the entire intervention. The mean age was 46.8 years, 88.5% were women and 55.1% were African-Americans. The low-carbohydrate group lost approximately 3.5 kg more body weight than did the low-fat group (P value: 0.002) over the course of the intervention. Both diets decreased total peptide YY and ghrelin. Compared to low-fat diets, the low-carbohydrate diet resulted in a significantly greater decrease in total peptide YY at 6 (Net change: -6.8 ph/mL; P value: 0.04) and 12 months (Net change: -10.6 ph/mL; P value: 0.02). The changes in total ghrelin were not significantly different throughout the study.
Our findings suggest that the low-carbohydrate diet did not result in a greater loss of appetite, compared to the low-fat diet.
- © 2013 by American Heart Association, Inc.