As we’re sure you know, being obese can wreck your health in a number of ways. It can cause high blood pressure (the leading cause of strokes), high cholesterol, diabetes and heart disease. But new research shows it’s messing with your fertility, too.

Read more: Is your sperm healthy and strong, use this checklist to find out

A study in the International Journal of Andrology analysed sperm samples from 1 285 men. They found that men who were clinically obese (this means having a BMI of 30 or higher) had lower volumes of semen, lower sperm counts, lower sperm concentration, lower sperm motility and greater sperm defects.

The scientists believe that the extra weight guys are carrying can disrupt hormone levels, throwing their ratios of testosterone and oestrogen out of whack.

Read more: 8 symptoms that mean your testosterone levels are low 

“The health and reproductive performance of spermatozoa in obese men are more likely to be compromised both qualitatively and quantitatively,” lead author of the study Dr Gottumukkala Ramaraju said in a press release.

“Results from our present data set suggest that efforts focusing on male weight loss before conception are warranted for couples seeking infertility treatment.”

Research has found that losing just 5% of your body weight can improve your health.

Read more: 5 things to do before noon to lose weight

Want to maximise your health? Make sure you’re cutting processed and sugary foods – like cake or white bread – from your diet and getting enough exercise. According to the CDC, you should get two hours and 30 minutes a week of moderate-intensity aerobic activity, or one hour and 15 minutes a week of high-intensity aerobic activity.

Additionally, you should include muscle-building workouts into your routine two or more days a week. Read this strategy of lifting weights to lose weight now.

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