Is SHBG useful for sleep?

SHBG (sex hormone-binding globulin) is not an established biomarker for sleep quality or sleep disorders. The scientific evidence for a direct benefit of SHBG testing in the context of sleep is weak and largely mechanistic. SHBG binds testosterone and estradiol; its levels are influenced by insulin, thyroid hormones, and liver function. Sleep deprivation can indirectly affect hormone profiles via cortisol and growth hormone changes, but SHBG does not respond specifically or sensitively to sleep. In clinical practice, SHBG is sometimes measured as part of a hormonal workup for conditions like PCOS, menopause, or hypogonadism – conditions that can be associated with sleep problems. However, an isolated SHBG value without clinical context is not informative for sleep optimization. Consumer lab tests that market SHBG as a 'sleep marker' overstate the current evidence. For improving sleep, focus on established factors: sleep hygiene, light exposure, stress management, and if needed, polysomnography. Note: SHBG levels are significantly affected by diet, body weight, and medications (e.g., oral contraceptives), further complicating interpretation.