Low HDL cholesterol is harmful.
HDL cholesterol is mainly synthesized in the liver and can reverse cholesterol transport, transferring cholesterol from the blood to the liver, thus reducing the possibility of atherosclerosis and protecting the cardiovascular. When HDL cholesterol is low, the ability to remove cholesterol from the blood is reduced, making the likelihood of cardiovascular disease more likely.
Slightly low HDL cholesterol generally has little effect, and a low-salt, low-fat diet is sufficient, but if it is significantly lowered or accompanied by elevated LDL cholesterol, it is necessary to go to a regular hospital for treatment.