Overweight males can double their sperm rely

Newswise – Men all over the world are suffering from deteriorating semen quality – often referred to as an outright fertility crisis.

Now, however, there may be good news for some of the men who are struggling.

In a new clinical study, researchers from the University of Copenhagen and Hvidovre Hospital show that obese men improve their semen quality when they lose weight — and maintain the weight loss.

“It was surprising to us that such a large improvement in semen quality could be shown in conjunction with weight loss. And since 18 percent of Danes suffer from obesity, this new knowledge could actually make a difference,” says Professor Signe Torekov, who led the study together with Professor Romain Barres at the Novo Nordisk Foundation Center for Basic Metabolic Research.

The new findings could be good news for fertility, as a link between higher sperm counts and achieving pregnancy more quickly has previously been shown.

The study was published in the respected journal Human Reproduction, which enjoys one of the highest rankings in the field of fertility. A total of 56 overweight men aged 18 to 65 and with a body mass index between 32 and 43 took part.

Sustainable weight loss necessary

Signe Torekov explains that obesity has long been known to be associated with reduced semen quality. Previous studies have also suggested a link between weight loss and increased semen quality, but those studies had so few participants or such modest weight loss that it was difficult to draw any conclusions, she explains.

“But now we are ready to do just that. This is the first long-term, randomized study in which we have shown that semen quality improves with sustained weight loss in obese men,” said Signe Torekov of the Department of Biomedical Sciences.

“The men lost an average of 16.5 kg eight weeks after the weight loss, which increased sperm concentration by 50 percent and sperm count by 40 percent. During the 52 weeks that the trial lasted after losing weight, the men maintained the improved semen quality. But only the men who maintained the weight loss: After a year, these men had twice as many sperm as before their weight loss. The men who regained weight lost the improvements in semen quality,” she explains.

Part of a larger study

The study is a sub-study of a major weight loss publication published in the New England Journal of Medicine in May 2021. A total of 215 obese Danes took part in the larger study. Among those participants, 56 of the men also provided semen samples to investigate whether semen quality and weight loss might be related.

In the study, all participants first followed an eight-week regimen of a low-calorie diet, which resulted in weight loss. Then the participants were randomly divided into four groups.

Two of the groups received placebo drugs, while the other two groups received anti-obesity drugs. Among the two placebo groups, one group was required to complete an exercise program that required them to complete at least 150 minutes of moderate exercise or 75 minutes of vigorous exercise — or a combination — each week.

The other group did not change their normal level of physical activity. The two groups that received anti-obesity drugs were divided into a group with and a group without an exercise program in the same way.

After one year, the group that exercised only and did not take any medication and the group that received only medication for obesity but did not take any medication were shown to maintain their weight loss of 13 kg. The group that received both anti-obesity drugs and exercised lost extra weight and improved health. The placebo group — those who thought they had been given medication but didn’t exercise — had regained half the weight loss, with many of the risk factors associated with developing type 2 diabetes and cardiovascular disease worsening.

Comments are closed.