Your cholesterol has a lot to do with increasing or decreasing your risk of heart disease. Over time, high levels of LDL cholesterol (bad cholesterol) and triglycerides can cause buildup on artery walls and lead to a heart attack. HDL cholesterol (good cholesterol) can protect against heart disease. Diet and exercise are two ways to lower cholesterol levels. Medications (e.g., statins) are available to treat high cholesterol (hypercholesterolemia). Low cholesterol can also cause or be an indication of other health problems, but is much less common.