Obesity is defined simply as too much body fat. Your body is made up of water, fat, protein, carbohydrate and various vitamins and minerals. If you have too much fat — especially around your waist — you're at higher risk for health problems, including high blood pressure, high blood cholesterol, diabetes, heart disease and stroke.
- Raises blood cholesterol and triglyceride levels.
- Lowers HDL "good" cholesterol. HDL cholesterol is linked with lower heart disease and stroke risk, so reducing it tends to raise the risk.
- Raises blood pressure levels.
- Can induce diabetes. In some people, diabetes makes these other risk factors much worse. The danger of heart attack is especially high for these people.
Even when there are no adverse effects on the known risk factors, obesity by itself increases risk of heart disease. It also harms more than just the heart and blood vessel system. It's a major cause of gallstones and can worsen degenerative joint disease.
Obesity is mainly caused by taking in more calories than are used up in physical activity and daily life. When people eat too many calories, or too much saturated fat, trans fat and cholesterol, their blood cholesterol levels often rise. That raises their risk of heart disease.