When a man experiences abnormal fatigue, decreasing libido and starts to gain weight around the middle, often the cause is a deficiency in the male sexual hormone testosterone.
Though this is typically a problem among older men, it is being diagnosed increasingly in younger men. Sometimes, however, the cause of the symptoms is unclear and a treatment is not necessary.
The problem affects a lot of men. The testosterone level in an estimated 20 percent of German men being treated by their general practitioner is too low.
"We have determined that 30 to 40-year-old men also can have low testosterone when certain factors combine," said Harald Joern Schneider, an endocrinologist at the University of Munich. These include weight gain, particularly at the waistline, and chronic conditions such as high blood pressure, high blood sugar, elevated blood lipids and obesity.
The reason excess weight plays such a role is fatty tissue contains an enzyme that transforms testosterone into oestrogen, the female hormone, said Jens Jacobeit, a physician in a Hamburg clinic that specialises in endocrinology.
Stress also enters into the picture as a possible trigger for the condition. The stress hormone cortisone suppresses testosterone production, said Jacobeit. A testosterone deficiency, however, can have other more clear-cut causes such as dysfunction of the pituitary gland or the testicles.
But the diagnosis can still raise questions because the symptoms vary and there is no symptom that without a doubt points to a testosterone deficiency, said Schneider. A series of things come into question, for example a reduction in sexual desire, difficulty in getting an erection, fatigue, a decline in muscle mass and an increase in body fat. There are, however, people with reduced to low testosterone values who live completely without problems.
"When a man wants a prescription for a testosterone supplement just because of low libido or erectile dysfunction, it is counterproductive because these symptoms often have entirely different causes," said Harald Klein, professor of general endocrinology at Ruhr University in Bochum, Germany. He rejects the idea of using testosterone as a lifestyle and anti-aging medicine. Too much testosterone can cause liver damage and any other risks of taking it are not yet known.
But a man who clearly has a deficiency should take a testosterone substitute. Otherwise, bone density can be affected, causing irreparable damage. A key point is that the patient should see an expert such as an endocrinologist or an andrologist, a physician who specialises in men's health.
"The diagnosis does not belong in the hands of an internist or general practitioner," said Jacobeit. And the specialist must carefully weigh the gains and the risks of a therapy. Often it's possible to resolve the problems without medicine.
"When the patient loses weight, he has a good chance of getting his testosterone level back to normal," said Schneider. The same is true when the recovery from a serious illness is successful. Becoming more physically active also can help raise the testosterone level, however, only an appropriate amount. Endurance sports such as marathon running can cause the level of testosterone to sink, he said