Effects of energy deprivation on sex hormone patterns in healthy menstruating women

To determine whether short-term energy deprivation affects sex hormone patterns, six healthy women were studied for two menstrual cycles. Two diets containing recommended levels of all nutrients and differing substantially only with respect to energy content were provided in sequence. During the first cycle, energy intake was 40 ± 2 kcal/kg body weight, and weight was essentially constant. For the second cycle, energy intake was reduced to 41% of the original intake, averaging 17 ± 1 kcal/kg initial body weight. During the low-energy diet, weight loss ranged from 3.2 to 6.7 kg. The two leanest women, who also lost the most weight, became anovulatory and amenorrheic in the low-energy period. Within a specific phase of cycle, however, the diet did not affect concentrations of estradiol, progesterone, luteinizing hormone, or follicle-stimulating hormone. Testosterone and androstenedione levels peaked midcycle normally and were decreased with the low-energy diet, while levels of sex hormone-binding globulin increased and those of dehydroepiandrosterone sulfate did not change. These results demonstrate short-term dietary and body composition effects on the menstrual cycle and serum androgens.