Drinking two cups of coffee a day could perk up performance in the bedroom, a study suggests.
Research found that men who drank two cups a day were 42 per cent less likely than non-drinkers to report erectile dysfunction. This fell slightly to 39 per cent for those who drank around three cups, the study of almost 4,000 men found.
The effect remained true regardless of whether men were overweight, obese or suffered from high blood pressure, the University of Texas study found.
However, the impact was reduced among men with diabetes, who have a high risk of erectile dysfunction, the study, in the journal PLOS ONE, found.
Doctors warn drinking more than four cups of coffee a day can be dangerous, causing restlessness, tremors, irritability, insomnia and stomach upset.
Prof David Lopez, of the University of Texas, Houston, said: “Even though we saw a reduction in the prevalence of erectile dysfunction with men who were obese, overweight and hypertensive, that was not true of men with diabetes.”
The researchers believe caffeine triggers a series of pharmacological effects that increase blood flow to the penis by relaxing arteries and muscle.
Women who drank at least one cup of coffee of coffee a day had a much higher rate of sexual activity, a study found
Estimates suggest that around half of men aged between 40 and 70 will suffer some degree of erectile dysfunction.
Data for the study came from the National Health and Nutrition Examination Survey and erectile dysfunction was assessed by a single question during a computer assisted interview. Two cups of coffee a day — between 85 and 170 milligrams of caffeine daily — was linked to a 42 per cent reduction in erectile dysfunction.
This fell slightly to 39 per cent for those who consumed between 171 and 303 milligrams, the equivalent of about three cups. Caffeine sources in the study included coffee, tea, fizzy drinks and sports drinks.
Previous research has also suggested that coffee could help boost a woman’s sex drive. Another group of US scientists found that caffeine increased the female libido in experiments on rats by it stimulating the part of the brain regulating arousal.
But researchers said a similar effect was only likely to be repeated in humans who did not drink coffee regularly.
And a study of sexual activity in the elderly revealed that women who drank at least one cup of coffee a day had a much higher rate of sexual activity, while men had a much higher potency rate.
In March a study suggested that drinking even more coffee — three to five cups a day — could reduce the risk of a stroke or heart attack. Research on 25,000 middle-aged men and women found that those who drank the least and most coffee had the greatest risk of coronary artery calcium — a sign that the arteries could be clogging, potentially causing heart disease.
There has been much debate over the effect of coffee consumption on heart health, with a number of studies coming to different conclusions.
Other studies have suggested coffee increases the risk of heart disease, by raising blood pressure and cholesterol.