How do SHBG levels change with age?

Sex hormone-binding globulin (SHBG) is a glycoprotein that binds sex hormones, particularly testosterone and estradiol, and plays a crucial role in regulating their bioavailability in the bloodstream. As individuals age, particularly after reaching adulthood, SHBG levels tend to increase. This increase can be attributed to several factors, including hormonal changes, increases in body fat percentage, and alterations in liver function, as SHBG is produced by the liver.

With aging, the body experiences a natural decline in the levels of sex hormones, specifically testosterone in men and estrogen in women. However, the liver may increase the production of SHBG in an attempt to adapt to the overall hormonal changes occurring in the body. This results in a higher ratio of SHBG-bound testosterone and estradiol, which can lead to varying effects on hormonal action as individuals grow older.

Understanding the dynamics of SHBG is essential for interpreting hormonal status, particularly in relation to obesity and metabolic health. With growing age and elevated SHBG levels, free and bioactive hormone levels may decrease, influencing various physiological processes and increasing the risk for a range of age-related conditions.

This information supports the conclusion that SHBG levels typically increase with age, rather than decrease, remain stable, or