MELATONIN & SLEEP: SCIENCE-BACKED, PLAIN-LANGUAGE GUIDE “Libido often reflects sleep, stress, and hormonal balance.” It’s difficult to claim a direct, consistent libido-boosting effect from melatonin. But poor sleep and circadian disruption can reduce sexual desire via fatigue, stress hormones, and altered sex-hormone rhythms. If melatonin improves sleep regularity, some people may experience indirect benefits—more energy, less stress, better daytime functioning. On the other hand, poorly timed dosing can cause morning grogginess and lower motivation. Increased sedation from combinations with other medicines can also negatively affect sexual desire. Persistent sexual difficulties warrant evaluation for underlying causes (sleep apnea, depression, thyroid issues, medication side effects, relationship factors). In short, melatonin is not a “sexual performance supplement.” Any benefit is typically indirect through improved sleep and circadian stability.