Sex Hormone Binding Globulin (SHBG)

Why is SHBG important for your Healthspan?

‍SHBG levels are important for maintaining hormonal balance, which is crucial for Healthspan, as they directly influence the biological activity of sex hormones like testosterone and estrogen. When SHBG levels are too high, fewer active hormones are available to tissues, potentially leading to symptoms of deficiency even with normal total hormone levels. Conversely, low SHBG can result in higher active hormone levels. These imbalances can affect muscle mass, bone density, energy, mood, and metabolic health, impacting long-term vitality and quality of life.

‍What is SHBG?

Sex Hormone Binding Globulin (SHBG) is a protein primarily produced by the liver that circulates in the bloodstream. Its main role is to bind to and transport sex hormones, particularly testosterone and estrogen. When SHBG binds to these hormones, they become inactive and are not readily available for use by cells and tissues.

The majority of SHBG circulates in the blood, but its concentration naturally fluctuates in women during the menstrual cycle. Levels are typically highest during the follicular phase (the first half of the cycle, before ovulation) and the ovulatory phase. Therefore, interpreting SHBG requires considering the timing of the test. SHBG acts as a regulator, controlling the amount of active sex hormones accessible to the body. Various other factors, including liver health, thyroid function, and insulin sensitivity, can also influence SHBG levels.

‍How do we take action?

If SHBG levels are found to be outside the typical range, one should consult with a healthcare provider to understand the implications, as SHBG is best interpreted in conjunction with total and free sex hormone levels. For women, testing should ideally be timed to a specific phase of the menstrual cycle (or performed frequently) to ensure results are interpreted accurately.

Elevated SHBG might suggest underlying liver or thyroid conditions. Low SHBG is often associated with insulin resistance, obesity, or hypothyroidism. Strategies to optimize SHBG and overall hormonal balance often include lifestyle modifications such as maintaining a healthy weight, regular exercise, optimizing blood sugar control through diet, and supporting liver health. Addressing any diagnosed underlying medical conditions is also important for restoring hormonal equilibrium and supporting overall Healthspan.

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Additional Sources

1. Wallace, I. R., McKinley, M. C., Bell, P. M., & Hunter, S. J. (2013). Sex hormone binding globulin and insulin resistance. Clinical endocrinology, 78(3), 321–329. https://doi.org/10.1111/cen.12086

2. Tchernof J -P, A. D. (2000). Sex Steroid Hormones, Sex Hormone-Binding Globulin, and Obesity in Men and Women. Hormone and Metabolic Research, 32(11/12), 526–536. https://doi.org/10.1055/s-2007-978681

3. Sá, E. Q., Sá, F. C., Oliveira, K. C., Feres, F., & Verreschi, I. T. (2014). Association between sex hormone-binding globulin (SHBG) and metabolic syndrome among men. Sao Paulo medical journal = Revista paulista de medicina, 132(2), 111–115. https://doi.org/10.1590/1516-3180.2014.1322666

4. Aribas, E., Kavousi, M., Laven, J. S. E., Ikram, M. A., & Roeters van Lennep, J. E. (2021). Aging, Cardiovascular Risk, and SHBG Levels in Men and Women From the General Population. The Journal of clinical endocrinology and metabolism, 106(10), 2890–2900. https://doi.org/10.1210/clinem/dgab470

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