Low testosterone levels more than affect men's sexual health; it can also increase the risk of depression, according to a new study.

Researchers from the George Washington University found that more than 50% of study participants who had low testosterone levels were also diagnosed with depression or carried the symptoms.

For the July 1 report published in the Journal of Sexual Medicine, researchers studied medical records of 200 men with a mean age of 47 years who had been advised to receive tertiary care for having testosterone levels recorded as "borderline low".

"In an era where more and more men are being tested for '"Low T' — or lower levels of testosterone — there is very little data about the men who have borderline low testosterone levels," said study researcher Michael Irwig of the George Washington School of Medicine and Health Sciences, adding that the team felt the need to study the mental health of men in that population.

The study found that 56 percent of men had depression or its symptoms; a quarter of the participants were on antidepressants; and most participants in the study were seen to be obese and physically inactive.

In those participants who had depressive symptoms or depression, erectile dysfunction, low energy, sleep problems, and decreased libido were some of the most reported symptoms.

Testosterone is an important hormone in males as it is responsible for many of the changes a man goes through during puberty. The hormone also helps with muscle development and pubic hair growth.

Sperm production is also controlled by the hormone. Basically, testosterone is responsible for the male sex characteristics; it is what "makes a man a man," as WebMD summed it up.

Based on the results of the new study, researchers suggest that clinicians should identify signs and symptoms of depression in patients who get treatment referrals for low levels of testosterone.

In addition, they should also take into account obesity and other unhealthy habits of the patients when deciding on a treatment plan.