Cholesterol Made Simple

Cholesterol metabolism is very complex and the following is simplified to make it easy to understand. Over the last 50 years, considerable progress has been made and the new drugs used to lower cholesterol are the result of research and understanding of cholesterol metabolism. For many years there was controversy concerning the role of cholesterol is the pathogenesis of atherosclerosis, but the debate is for the most part over.

Cholesterol is absorbed in foods and made by the liver. The blood level is determined by the number of receptors on the liver that degrade cholesterol. What you eat and weight gain play a role, but a liver with an abundance of LDL receptors will keep your cholesterol down.

A simple way to understand cholesterol is to consider the components-cholesterol, LDL (low density lipoprotein or bad cholesterol) HDL (high density or good cholesterol and triglyceride. LDL circulates and deposits cholesterol is arteries; HDL circulates and removes cholesterol from arteries, returns it to the liver, and the LDL receptor breaks it down. Simple, easy to understand, and mostly correct.

Triglyceride plays a role in contributing to “bad particles.”

The emphasis has been to lower total cholesterol and LDL cholesterol. Diet has been the main therapy until the statins were introduced in the last 10-15 years. They work at the early stages of cholesterol production. So far, they have been very safe and effective. LDL and total cholesterol levels can be reduced effectively with once a day dosing. Studies show that lowering cholesterol seems to reduce mortality at all age groups-even old seniors. It has not been used much in the pediatric population, but may be selectively indicated.

A new drug Zetia decreases the absorbtion of cholesterol.

The has been active research on drugs that will elevate the HDL molecule. So far, this has not been successful, but if HDL can be elevated, it is protective and reduces risk factors. When we see patients with high HDL levels, we are much less aggressive in reducing cholesterol/LDL. Recently, a study was reported on infusing HDL like drugs into patients. In 5 weeks, there was a reduction in arterial wall plaques, so this may be a therapy for the future.

My approach is to try to reduce cholesterol/LDL aggressively. The current guidelines recommend a cholesterol less than 200 and an LDL less than 100. I try to do better than this for myself.

More resources on Cholesterol:

www.lifeclinic.com
www.americanheart.org
www.fda.gov
www.nhlbi.nih.gov

Written & edited by Robert E. Dyer, MD