File photo: Making love several times a week can slash levels of homocysteine – a chemical in the blood that can trigger cardiac problems, a study found. Picture: Supplied

Men rarely require much encouragement to indulge in a night of passion but now they can argue it’s good for their health.

Scientists have revealed that enjoying regular sex could be the best remedy for avoiding killer heart disease – although somewhat unfairly, only for the male of the species.

Making love several times a week can slash levels of homocysteine – a chemical in the blood that can trigger cardiac problems, a study found.

But women do not get the same benefit because their sexual arousal is less dependent on a healthy blood flow, experts said.

Men who enjoy regular sex sessions often have better circulation and healthier blood vessels, which helps prevent a build-up of homocysteine. 

Doctors have long suspected that frequent sex can reduce the risk of heart attacks. A previous study found intercourse twice a week halved a man’s chances of clogged arteries compared to those indulging less than once a month.

But until now there has been little scientific evidence to explain why a healthy sex life protects against illness. The latest findings, published in the Journal of Sexual Medicine, are to the first reveal the link with reducing homocysteine levels.

The chemical is a vital building block of proteins and occurs naturally in the body. But excess levels, which can be caused by poor diet, are thought to damage blood vessels supplying the heart – raising the risk of a deadly clot forming.

Previous studies have linked high readings with a 66 percent increased chance of dying from heart disease, as well as higher risks of stroke, Alzheimer’s and cancer.

Researchers from the National Defence Medical Centre in Taiwan tracked more than 2 000 men and women aged 20 to 59.

Analysing blood samples, they compared homocysteine readings to frequency with which volunteers had sex.

The lowest traces were found in men claiming to have sex at least twice every week, while the highest readings were found in those restricted to less than once a month. But in women there was no significant variation.

Researchers are now calling on doctors to advise male patients at risk of heart disease to have more sex.

They wrote in a report: "A good quality sex life, frequent sex and libido are all related to health in the middle-aged and elderly.

"Increased sexual frequency could have a protective effect on general health and quality of life – especially in men – so doctors should support patients’ sexual activity."

Dr Mike Knapton, of the British Heart Foundation, said the study produced an "interesting result" but did not prove regular sex reduced homocysteine levels.

He added: "A relationship does exist between sex and heart disease risk.

"Checking your blood pressure and cholesterol, as well as keeping active and not smoking, remain the best ways to ensure a healthy future."