We conducted a prospective analysis of 47 911 men in the Health Professionals Follow-up Study who reported intake of regular and decaffeinated coffee in 1986 and every 4 years thereafter.

FORBES: Coffee Addiction Cuts Cancer Risk

Sarah Schenker, a dietician for the British Nutrition Foundation, said there was nothing wrong with people drinking three or four cups of coffee a day - provided that they also drank water or other decaffeinated drinks to compensate.

BBC: Caffeine 'reduces productivity'