What Is SHBG?
Sex hormone-binding globulin (SHBG) is a protein made by the liver that binds tightly to testosterone and estrogen in your blood. When hormones are bound to SHBG, they aren't available for your body to use.
Only a small fraction of testosterone is "free," and that's the part that's active in your tissues. SHBG largely determines how much is free.
Why SHBG Matters
Your total testosterone can look normal while your free testosterone is low—if your SHBG is high. Or total testosterone can look low while free testosterone is fine—if SHBG is low.
That's why SHBG is important for interpreting hormone results in both men and women.
What Raises SHBG?
- Aging
- Hyperthyroidism
- Liver conditions
- Oral estrogen and some birth control pills
- Very low body fat or calorie restriction
- Certain medications
High SHBG can lead to symptoms of low testosterone even when total testosterone looks normal.
What Lowers SHBG?
- Insulin resistance and type 2 diabetes
- Obesity
- Hypothyroidism
- Polycystic ovary syndrome (PCOS)
- Use of anabolic steroids
Low SHBG is often a sign of insulin resistance and is linked to higher risk of type 2 diabetes. In women, low SHBG can lead to higher free testosterone and symptoms like acne or excess hair growth.
What Is DHEA-S?
DHEA-S (dehydroepiandrosterone sulfate) is a hormone made mainly by the adrenal glands. It serves as a building block for testosterone and estrogen.
- DHEA-S naturally declines with age
- Very low levels may point to adrenal issues
- High levels can be seen in conditions like PCOS or, rarely, adrenal tumors
Checking DHEA-S alongside testosterone and SHBG helps clarify where hormones are coming from.
Interpreting Your Panel
A complete picture often includes total testosterone, free testosterone, SHBG, estradiol, and DHEA-S, interpreted together with your symptoms.
Learn more about lab testing here: Heva Lab Testing
The Bottom Line
SHBG controls how much of your testosterone is actually usable, so it's essential for interpreting results. DHEA-S adds insight into adrenal hormone production. Together, they give a much clearer hormone picture.