Study participants with low levels of the male hormone saw a dramatic increase in insulin sensitivity after testosterone replacement therapy.
An inability to respond to insulin is one of the hallmarks of type 2 diabetes.
The same scientists showed in 2010 that low testosterone is closely associated with the disease in men. A third of type 2 diabetes sufferers were found to have low levels of the hormone, whether or not they were obese.
In the new study that included 44 diabetic men lacking testosterone, injections of the hormone increased the body’s response to insulin – as measured by tissue-uptake of glucose – by 32 per cent.
The findings are published in the journal Diabetes Care.