The hormone testosterone stands to represent many different things. It's often associated with manliness, strength, risk-taking behaviour and a man's bravado. But in scientific terms, testosterone is one of the most important male hormones. It not only plays an important role in red cell production, maintaining muscle strength and sex drive but also helps ensure overall health. Testosterone is also produced by females, although in much smaller quantities.
Testosterone levels vary from person to person and even vary depending on when they're being measured. Several studies stress on how important it is to have an optimum level of testosterone in the body. This was illustrated by two separate studies at ENDO 2015, the annual meeting of the Endocrine Society in San Diego.
One of the two studies conducted at Harvard Medical School found that high levels of testosterone can put a man at the risk of heart disease. These chances get worse with lower levels of estrogen. The study, conducted in 400 healthy men aged 20 to 50, found that higher levels of testosterone led to lower levels of HDL cholesterol or 'good' cholesterol while estrogen appeared to have no effect on HDL cholesterol.
In contrast, the investigators reported that low levels of estrogen led to higher fasting blood glucose (sugar) levels, worsening insulin resistance and more fat in muscle, markers for developing diabetes which is itself a risk factor for heart disease. According to Elaine Yu, lead investigator and assistant professor at Harvard Medical School, "These observations may help explain why men have a higher risk of cardiovascular disease."
On the other hand, lower levels of testosterone also pose a serious threat. Men with low levels of testosterone have higher rates of depression and depressive symptoms than the general population.
"This study found that men seeking management for borderline testosterone have a very high rate of depression, depressive symptoms, obesity and physical inactivity," said principal study author Michael Irwig, associate professor at George Washington University.
He added, "Clinicians need to be aware of the clinical characteristics of this sample population and manage their comorbidities such as depression and obesity."
The researchers studied 200 adult men between 20 and 77 years of age whose testosterone levels were borderline (between 200 and 350 nanograms per decilitre). They remeasured the men's total testosterone and assessed depression from their medical history and depressive symptoms with the validated Patient Health Questionnaire 9 (PHQ-9).
The researchers found that 56 percent of the study participants had significant depressive symptoms, known diagnosis of depression and/or use of an antidepressant. The population also had a high prevalence of overweight (39 percent), obesity (40 percent) and physical inactivity. More than half of the men were not found to be engaged in regular exercise.
The most common symptoms reported were erectile dysfunction (78 percent), low libido (69 percent) and low energy (52 percent).
With inputs from IANS