Scientists found that having a beer belly or muffin top around your middle, even if you are not overweight, poses a greater risk than being obese or carrying fat elsewhere.
It is thought a podgy tummy can be a killer because it is packed with “bad fat”.
Researchers at Brigham and Women’s Hospital in Boston, USA, sought to find a link between the location of body fat and risk factors for heart disease and cancer.
They assessed fat around the abdomen, heart tissue and aortic artery of 3,086 men and women with an average age of 50.
Over a period of up to seven years, there were 90 cardiovascular events, 141 cancer cases and 71 deaths.
Abdominal fat – typically an indicator of fat around internal organs – was associated with heart disease and cancer after adjusting for clinical risk factors and general obesity.
Maureen Talbot, senior cardiac nurse at the British Heart Foundation, said: "We already know that excess stomach fat increases your risk of developing heart disease but this research confirms there is a greater risk even if you have a normal BMI (body mass index)"
“The dangers of abdominal fat can’t be ignored and nor can the importance of measuring waist circumference when it comes to assessing heart disease risk.
“You can help keep control of your weight by eating a healthy balanced diet and getting plenty of exercise.”
Dr Kathryn Britton, who led the study published online in the Journal of the American College of Cardiology, said: “Identification of high-risk individuals is important as it allows targeting of preventive and therapeutic measures.”