The increase in cholesterol when a person is thin may be due to family genetics, improper diet, slow metabolism and other reasons. 1. Family genetic inheritance: some people have standard body weight, or even thinness, but they are affected by family genetic factors, such as the presence of familial hypercholesterolemia and other diseases, and may still have a high total cholesterol phenomenon. 2. Improper diet: If an individual is thin, but often consumes high salt and high fat food, it may also cause cholesterol elevation. 3. Slow metabolism: If an individual is thin, but exercises less or is older, he or she may have a slow metabolism, which may cause cholesterol elevation. If the phenomenon of elevated cholesterol, you should go to the hospital in a timely manner to improve the examination, clear diagnosis, and carry out targeted treatment as soon as possible to avoid delaying the condition, in order to prevent the triggering of other cardio-cerebral vascular problems.