Effects Of a Six-Week Watermelon Supplementation On Insulin Resistance and Food Intake Signaling In Free-Living, Overweight Post-Menopausal Women

Obesity is associated with hormonal disruption involving food intake, and post-menopausal women have a higher propensity to be overweight. PURPOSE: Investigate the effects of six-weeks of watermelon supplementation on insulin resistance and food intake signaling in free-living, overweight, post-menopausal women. METHODS: Subjects (60.1±6.8 years old and 59.5±5.2 years old, control and watermelon, respectively throughout) were overweight (82.5±14.5 kg and 84.2±17.1 kg, respectively) and randomly assigned to either the watermelon or control treatment groups. The watermelon group consumed 710 mL of watermelon puree per day for six weeks. The control group served as a time control. Both groups maintained lifestyle and body mass. Fasting blood was collected pre- and post-six-week supplementation. RESULTS: Watermelon supplementation increased L-arginine (p<0.05), but did not change glucose, insulin, or Homeostatic model assessment of insulin resistance (p>0.05). The hunger and satiety peptides also did not change as a result of watermelon supplementation: Ghrelin, leptin, glucose-dependent insulinotropic polypeptide, glucagon-like peptide 1, or peptide YY (p>0.05). The control group, however, showed increased levels of PYY (p<0.05). There was also a main effect of time for leptin, insulin, and GLP-1 (p<0.05). CONCLUSIONS: Six-weeks of watermelon supplementation did not impact insulin resistance or food intake signaling in free-living, overweight, post-menopausal women.