Testosterone is a hormone that automatically makes you think of strong, muscle-building men.

While this hormone does help build muscle mass, it's also in charge of developing male characteristics, bone growth, sexual function and suitable levels of red blood cells.

As men age, their testosterone levels begin to diminish, just like women experience lowered estrogen levels. However, certain diseases, injuries and stress can also contribute to the loss of testosterone.

When testosterone levels go down, how can you tell?

Some key indicators include a spike in cholesterol, blood pressure and blood sugar and an increased risk of low sex drive and erectile dysfunction.

What types of solutions are available for low testosterone?

For men under the age of 50, a more natural approach is to take clomiphene, which helps stimulate the body's own ability to produce testosterone.

In men over the age of 50, it's recommended to use bio-identical testosterone, a replacement therapy that restores testosterone levels back in the body.

Director of the Fatigue and Fibromyalgia Practitioners Netowrk, Dr. Jacob Teitelbaum, MD, discusses with Dr. Holly the reason why testosterone levels drop, as well as alternatives to help reduce lower testosterone levels.