Testosterone Blood Test

Free Testosterone Index (FTI) is a measure of the amount of testosterone available in the blood. It helps assess androgen status in both men and women.

The primary male sex hormone, also important in women at lower levels. Testosterone regulates muscle mass, bone density, fat distribution, libido, and mood. Levels decline naturally with age in both sexes.

The most potent and prevalent form of estrogen. In women, estradiol regulates the menstrual cycle, fertility, and bone density. In men, it's produced from testosterone and plays roles in bone health and libido. Levels vary significantly with age and menstrual cycle.

A protein that binds and transports sex hormones (testosterone, estrogen) in the blood. High SHBG reduces the amount of free, active hormones available. SHBG increases with age, thyroid hormones, and estrogen; decreases with obesity and insulin resistance.

The primary stress hormone, produced by the adrenal glands. Cortisol regulates metabolism, immune response, blood pressure, and the sleep-wake cycle. Chronically elevated cortisol from stress contributes to weight gain, immune suppression, and metabolic dysfunction.

The sulfated, stable form of DHEA with a long half-life, making it the preferred test for adrenal androgen production. DHEA-S is the most abundant circulating steroid hormone and a key longevity biomarker.

The unbound, biologically active fraction of testosterone (typically 1–3% of total). Free testosterone is the form that can enter cells and exert effects. More clinically relevant than total testosterone for assessing hormonal status.

Regulates reproductive function in both sexes. In women, FSH stimulates egg development; elevated levels indicate declining ovarian reserve or menopause. In men, FSH stimulates sperm production.

Works with FSH to regulate reproductive function. In women, an LH surge triggers ovulation. In men, LH stimulates testosterone production. Abnormal levels can indicate pituitary or gonadal disorders.