Magnitude of daily energy deficit predicts frequency but not severity of menstrual disturbances associated with exercise and caloric restriction.

Abstract in brief

• The study found that the more energy deficit women experienced from exercise and caloric restriction, the more likely they were to have menstrual disturbances, with a clear dose-response relationship, but the severity of these disturbances did not increase with larger energy deficits.
• Women in moderate (ED2) and severe (ED3) energy deficit groups had more menstrual issues like luteal phase defects, anovulation, and oligomenorrhea compared to controls, with energy deficits ranging from about 470 to 810 kcal/day.
• The overall percentage of energy deficit was the main factor predicting how often menstrual disturbances occurred, independent of weight loss, highlighting that energy deficiency itself, rather than weight loss, affects menstrual health.]