Sleep

Testosterone and sleep run in both directions: poor sleep lowers testosterone, and testosterone therapy can change how you sleep. Most of your daily testosterone is produced during sleep, and chronic short sleep can cut levels by 10-15% — while untreated sleep apnea is both a major cause of low T and a condition the Endocrine Society says should be treated before starting TRT. Here’s how the relationship works, what to expect in your first month, and when to get a sleep study first.