'Testosterone jab can protect against heart attacks'

Researchers found that men who were offered a course of five injections saw their sex drive improve dramatically as well as their fitness levels, mood and their ability to concentrate.

During the US study, people who said they had a low libido dropped from 64 per cent before the treatment to ten per cent, the 'Daily Mail' reported.

"The results are impressive. The reduction in erectile dysfunction was highly significant," Professor Hugh Jones, consultant endocrinologist at Barnsley Hospital, and co-author of the study, said.

Although the study was carried out on men with medically deficient levels of testosterone, known as hypogonadism, experts believe the findings could be relevant to the far larger group whose testosterone has simply dropped to the low end of normal