A 2014 study published in the journal PLoS One found that a diet rich in foods including fish, especially fatty fish, increased the size of HDL particles, which may help improve cholesterol transport throughout the body. The American Heart Association recommends eating fish at least twice a week, especially varieties that contain omega-3 fats, such as salmon, trout, and herring. A serving is considered 3.5 ounces cooked.
Weight Management. If you are overweight, losing weight can help lower your LDL (bad) cholesterol. This is especially important for people with metabolic syndrome. Metabolic syndrome is a group of risk factors that includes high triglyceride levels, low HDL (good) cholesterol levels, and being overweight with a large waist measurement (more than 40 inches for men and more than 35 inches for women).
HDL is more tightly controlled by genetic factors than are the other lipoproteins (ie, LDL, very–low-density lipoprotein (VLDL), intermediate-density lipoprotein [IDL], chylomicrons). For example, in certain families, especially some families with Japanese ancestry, a genetic deficiency of cholesteryl ester transfer protein (CETP) is associated with strikingly elevated HDL-C levels. 
Get Moving – Want healthy HDL levels? It’s time to lace up those sneakers and start exercising! Being physically active is essential for a healthy heart. Many types of exercise will help raise your HDL cholesterol, including high-intensity exercise, aerobic exercise, and strength training. Shoot to exercise most days out of the week for at least 30 minutes each session to experience the benefits.