Males with low testosterone levels are at a higher risk for heart disease, but new evidence suggests that levels could be improved by a hormone named after chocolate.

After being given a hormone known as kisspeptin, a group of scientists from the University of Edinburgh discovered that men’s testosterone levels can increase. The hormone was found in the city of Hershey, Pennsylvania, famous for chocolate, therefore, it was named after the infamous Hershey’s chocolate kiss.

The study was published in the journal Clinical Endocrinology and funded by the Medical Research Council.

Based on earlier research, this study shows a relationship between low testosterone and diabetes. This may be caused by a resistance to insulin, the hormone that influences blood sugar. One-third of men with type-2 diabetes, which is also a risk factor for heart disease, have low testosterone.

In their previous research, the University of Edinburgh established that low testosterone levels in fat tissues were directly linked to the onset of type 2 diabetes. The evidence revealed that insulin resistance happened when testosterone was not functioning correctly, regardless of body wegiht.

A study from 2010 established that obesity is associated with low testosterone levels. Men with higher BMI numbers showed lower levels of testosterone. Obesity has already previously been linked with a higher risk for heart disease and diabetes.

During the study, the investigators gave kisspeptin to men with both type-2 diabetes and low testosterone. Kisspeptin, which is made by the human body, was given over a 12-hour period using a drip.

Low testosterone is increased by using supplementary gels or injections. Sometimes, this may cause unusually steep levels of testosterone, resulting in mood changes, temporary infertility, acne and other side effects.

The researchers found that when kisspeptin was administered, levels of testosterone did not rise above the typical range.

Dr Jyothis George, of the MRC Centre for Reproductive Health at the University of Edinburgh, said:

“We know that low testosterone leads to an increased risk of heart disease. This treatment shows that kisspeptin can stimulate the body’s own production of testosterone, without testosterone levels becoming too high. We hope that, with further research, kisspeptin could potentially be used to treat testosterone deficiency.”

The study was conducted using five male patients with diabetes, low testosterone levels and had an average age of 34 years. The control group were volunteers who were generally healthy. In the future, the authors would like to conduct a larger study with a wider range of participants.

The investigators also want to explore the methods in which kisspeptin can be given over a longer-time period, for example using slow-release injections under the skin.

Written by Kelly Fitzgerald