Overweight and blood cholesterol – One of the adverse effects of being overweight is that your cholesterol levels are affected unfavorably. Basically, body cholesterol levels are made up of several types of cholesterol including HDL, which protects the heart and LDL, which increase heart disease risks. As far as your health and fitness is concerned, your aim should be to increase HDL and decrease LDL. When you gain weight, you tend to have the reverse effect on your blood lipids.