Men who have sex at least twice a week can almost halve their risk of heart disease, according to new research. It shows men who indulge in regular lovemaking are up to 45 per cent less likely to develop life-threatening heart conditions than men who have sex once a month or less. The study, of over 1,000 men, shows sex appears to have a protective effect on the male heart but did not examine whether women benefit too. Now the American researchers who carried out the investigation are calling for doctors to screen men for sexual activity when assessing their risk of heart disease. Although sex has long been regarded as good for physical and mental health, there has been little scientific evidence to show the full benefits that frequent intercourse can have on major illnesses such as heart disease. An earlier study at the National Cancer Institute in the US showed men who ejaculated through sex or masturbation at least five times a week were much less likely to get prostate cancer.