Bioactive Testosterone
Bioactive testosterone is the part of testosterone that is free or loosely bound to albumin and readily available to the tissues.
Bioactive testosterone is the part of testosterone that is free or only loosely bound to albumin, and therefore readily available to tissues such as muscle and bone. Testosterone that is tightly bound to SHBG is not included. The value adds context to total testosterone.
Age, sleep, stress, body weight and physical activity all affect it. The level of SHBG matters a lot: more SHBG leaves less bioactive testosterone. Testosterone is also higher in the morning, and anabolic steroids raise it.
Foods that help
Protein from eggs, fish and meat, zinc from shellfish, pumpkin seeds and legumes, healthy fats from olive oil, nuts and avocado, and vitamin D from fatty fish.
Foods to limit
A lot of alcohol, sugar and highly processed food.
Track it through the year
One value is a snapshot. Following it up shows whether what you changed is working.
Related markers
Educational information only — not a diagnosis. Every result is checked against safe limits, and anything critical is escalated for follow-up.
See all 84 markers →