What is Sex Hormone-Binding Globulin?

Sex Hormone Binding Globulin (SHBG) is a protein that's made by your liver. It has an important job: carrying and controlling sex hormones in your body, like testosterone and estrogen. When a hormone is bound to SHBG, it is no longer active as tissues can only use free (not bound) hormones.

Why is it included in Hormone+?

SHBG is included in the SiPhox Health Hormone+ panel for both males and females.

Males typically take this test to resolve issues related to high SHBG. This is because an excess of SHBG will bind to more testosterone, leaving less free testosterone available for use by the body. On the flip side, females typically take this test when SHBG is low as this results in abnormally high amounts of active, free testosterone.

When total testosterone levels are within the normal reference range, infertility, low libido, and/or erectile dysfunction are a few reasons why SHBG levels are tested in males. Females often check SHBG levels when experiencing infertility, acne, irregular or lack of menstruation, and/or excess hair growth.

    How can I better understand my results?

    SHBG could be influenced by other underlying conditions. Abnormally high levels of SHBG may be indicative of pregnancy, weight loss, hepatitis B or C, hemochromatosis, hyperthyroidism, and a few other conditions. Abnormally low levels could be caused by obesity, insulin resistance (possibly related to metabolic disease or diabetes), PCOS, fatty liver disease, or other factors.

    According to Mayo Clinic Laboratories, normal reference ranges for adults are:

    • Males: 13.3-89.5 nmol/L
    • Females (nonpregnant, menstruating): 18.2-135.5 nmol/L
    • Females (nonpregnant, menopausal): 16.8-125.2 nmol/L

    For a male age breakdown, Exeter Clinical Laboratory includes reference ranges:

    • < 50 years old: 18.3 - 54.8 nmol/L
    • > 50 years old: 20.6 - 76.7 nmol/L

    SHBG is expected to increase in males and decrease in females with age, but other factors including obesity and underlying conditions may vary the normal range. For this reason, please consult with your physician if you are concerned about any of your biomarker values.

    If your SHBG is elevated, you can try:

    If your SHBG is low, you can try:

    Where can I learn more?

    University of Rochester - SHBG

    Helios Telemedicine for Longevity (video) - What Is SHBG & Why Is It Important For Men?