If you have developed a spare tyre it is time you saw a doctor to assess your cardiovascular health as researchers have found that belly fat even in people who are not otherwise overweight is bad for the heart. People with a normal weight but a fat belly have more chance of heart problems than people without a fat belly even if they are obese according to BMI (body mass index) said study author Jose Medina-Inojosa from the Mayo Clinic in Minnesota US. This body shape indicates a sedentary lifestyle low muscle mass and eating too many refined carbohydrates Medina-Inojosa