testosterone

Testosterone is a sex-steroid hormone present in people of all sexes. Its effects depend partly on its balance with estrogen, and levels vary between individuals and over the lifespan. 1

• Behavior: Testosterone can increase libido, novelty-seeking, and willingness to compete, and can lower anxiety; it tends to amplify behaviors or tendencies already present rather than determine a person’s character. 2 3
• Women also produce it: In premenopausal women, ovarian theca cells can produce testosterone. 4
• Hormone therapy needs medical oversight: The discussion highlights potential risks—including acne, hair loss, mood changes, fertility concerns, and cardiovascular or lipid issues—and recommends close physician monitoring. 5
• Checking levels: Huberman recommends evaluating hormone results with a doctor, ideally an endocrinologist. 6