Information for patients

Testosterone replacement therapy improves glucose control and reduces central obesity in men with metabolic syndrome and low testosterone

Image: analyzing blood glucose

This study carefully evaluated available good quality studies that compared the levels of testosterone in men with or without the metabolic syndrome to see if metabolic syndrome is linked to low testosterone. The study also looked at the effects of testosterone replacement therapy on components of the metabolic syndrome.

Key Findings

  • Men with metabolic syndrome had lower levels of testosterone in the blood than men without metabolic syndrome
  • This was also true when men with or without erectile dysfunction were evaluated
  • If men also had type 2 diabetes, the decline in their testosterone levels was even greater
  • When hypogonadal men with metabolic syndrome were treated with testosterone replacement therapy, components of the metabolic syndrome improved, including reduced waist circumference, improved blood glucose control and improved blood lipid profiles.

Source: Testosterone and metabolic syndrome: a meta-analysis study. Corona G, Monami M, Rastrelli G, et al. J Sex Med 2011;8(1):272-283.

Background information

The metabolic syndrome is a group of interrelated risk factors, including:

  • A large waistline (central obesity)
  • A higher than normal lipid (fat) level in the blood – in particular raised levels of triglycerides
  • A lower than normal level of ‘good’ high-density lipoprotein (HDL) cholesterol in the blood
  • Higher than normal blood pressure
  • Higher than normal blood sugar levels.

Having three or more of these components or characteristics is sufficient for a diagnosis of metabolic syndrome. Metabolic syndrome is associated with:

  • A doubling of the 5- to 10-year risk of developing cardiovascular disease
  • A 5-fold increase in the risk of developing type 2 diabetes
  • A higher likelihood of having erectile dysfunction or low testosterone levels.

Having low testosterone (also known as hypogonadism) and/or erectile dysfunction is also a warning sign for a number of disease conditions, including heart disease and type 2 diabetes. Therefore, the presence of low testosterone and erectile dysfunction in men with metabolic syndrome may help to alert healthcare professionals to the need to recommend lifestyle changes or to consider starting testosterone replacement therapy.

Testosterone replacement therapy has been shown to:

  • Improve blood glucose control
  • Reduce central obesity
  • Improve lean muscle mass
  • Improve cholesterol levels
  • Reduce warning signals for diabetes, thickening of the arteries (atherosclerosis) and the metabolic syndrome.

Until now, there have been few studies specifically investigating whether testosterone replacement therapy benefits metabolic syndrome in men with low testosterone. This study is important because it confirms that testosterone replacement therapy is able to improve central obesity and other factors related to insulin resistance (decreased ability of the body to process sugars and fats) in men with metabolic syndrome. The study also confirms that metabolic syndrome and low testosterone are linked, especially in men with erectile dysfunction.

Last updated: 2019