Free Testosterone Booster

Testofen has been shown in clinical trials to boost free testosterone levels. But what is free testosterone?

Fight Depression by Raising Free Testosterone

Testosterone’s effects can be felt above the belt, too. A 2008 Archives of General Psychiatry study found that older men with the lowest levels of free testosterone were at a higher risk for depression than men with the highest levels. Researchers haven’t pinpointed the link, but other studies have shown that waning testosterone levels may lead to increased fat mass, irritability, and a lower sex drive.

To help sustain testosterone levels, Kleiner recommends bagging 30 percent of your calories from healthy fats, such as the monounsaturated and polyunsaturated fats found in olives, fish, nuts, and avocado.

Only about 2 percent of the total testosterone in the plasma of men is free or nonprotein bound; about 1 percent in women. In most men and women, more than 50 percent of total circulating testosterone is bound to sex hormone-binding globulin (SHBG), and most of the rest is bound to albumin. It is only the free or nonprotein bound testosterone which is the hormonally active form, able to interact with cellular hormone receptors. SHBG-bound testosterone is not readily available for intracellular complex formation because of SHBG’s high binding affinity for testosterone.

Testosterone-bound SHBG is considered biologically inactive. SHBG levels are sensitive to changes in estrogen and testosterone. Thus conditions which affect SHBG will directly affect the serum levels and biological activity. Some interfering effects include:

Decreased serum testosterone levels stimulate the production of SHBG by the liver
Increased estrogen levels that occur in pregnancy or with estrogen replacement therapy also increase SHBG production
SHBG levels can also be increased in patients with hyperthyroidism and liver disease
Increased SHBG-bound testosterone can result in total testosterone levels in the normal range, despite a clinical deficiency of bioavailable testosterone
SHBG levels tend to be low in androgen excess states, often resulting in total testosterone levels within normal limits and elevated bioavailable testosterone