BACKGROUND<\/p>\n
The aim of this study was to determine if oral contraceptive (OC) use affects body weight, body composition and metabolism in primates.<\/p>\n
METHODS<\/p>\n
Reproductive-age female rhesus monkeys of normal and obese BMI were studied to document baseline weight stability, then treated continuously with an OC (dosed to achieve equivalent human serum levels for a 30 µg ethinyl estradiol\/150 µg levonorgestrel preparation) for 237 days. Monkeys were monitored for changes in body weight, levels of physical activity (measured by a triaxial Actical accelerometer), food\/caloric intake, percent body fat (dual energy X-ray absorptiometry, DEXA) and metabolism (24 h metabolic rate and serum metabolic substrate and hormone concentrations).<\/p>\n
RESULTS<\/p>\n
All 10 monkeys completed the study protocol with no adverse events. While body weight (–0.73% change) and percent body fat (–1.78% change) of the normal BMI group did not significantly decrease from baseline, obese monkeys showed a significant decrease in body weight (–8.58% change, P<\/I> < 0.01) and percent body fat (–12.13% change P<\/I> = 0.02) with OC treatment. In both the obese (P<\/I> = 0.03) and the normal BMI (P<\/I> = 0.01) groups, there was a significant increase in basal metabolic rate with OC use. No changes were seen in food intake, activity level or % lean muscle mass with OC use for either BMI-based group.<\/p>\n
CONCLUSIONS<\/p>\n
Overall, OC use appears to cause a slight increase in basal metabolic rate in female monkeys, leading to a decrease in body weight and percent body fat in obese individuals.<\/p>\n","protected":false},"excerpt":{"rendered":"
BACKGROUND The aim of this study was to determine if oral contraceptive (OC) use affects body weight, body composition and metabolism in primates. METHODS Reproductive-age female rhesus monkeys of normal and obese BMI were studied to document baseline weight stability, … Continue reading