Causes of high cholesterol include such lifestyle choices as diet, weight and activity levels, but they also include genetic makeup, according to Mayo Clinic. Both family history and lifestyle play a role in one's cholesterol totals.
Cholesterol comes in three types: HDL, LDL and VLDL. The HDL, or high-density lipoprotein, is known as the "good" cholesterol, as it gathers excess cholesterol from around the bloodstream and transports it to the liver. The liver then filters the cholesterol out, converting it to waste matter, according to Mayo Clinic.
LDL, or low-density lipoprotein, is known as "bad" cholesterol, notes Mayo Clinic. This builds up along the walls of the arteries, causing them to harden and get narrower. VLDL, or very low-density lipoprotein, has the most triglycerides. VLDL cholesterol increases the size of LDL cholesterol particles, making blood vessels even narrower.
People who are inactive, overweight and who eat unhealthy foods are likely to have the highest levels of LDL cholesterol and the lowest levels of HDL cholesterol, notes Mayo Clinic. Even people who lead a healthy lifestyle may have higher levels of cholesterol as a result of family history. Genetic factors may hinder cells from taking LDL cholesterol out of the blood efficiently, or they may cause the liver to make too much cholesterol.