jump to navigation

The Cholesterol Story May 27, 2010

Posted by Dr. Jacqueline E. Campbell in Cholesterol, Health, Wellness.
Tags: , , , ,
add a comment

Many persons become frightened when told that their cholesterol levels are elevated.  They immediately think that just the elevation of cholesterol places them at “heart attack door”.  The truth is that there is more to cholesterol than that! High cholesterol does not reliably identify all people with hidden heart disease, nor does just lowering it cure anyone of heart disease.

Cholesterol is a soft, waxy substance made by the body.  It is found among the fats in the bloodstream and in all your body’s cells.  Cholesterol is not a “bad guy”.  It is beneficial to the body.  Our bodies need it to form cell membranes, to produce bile acids for digestion and to make hormones and vitamin D.  Cholesterol and other fats cannot dissolve in the blood.  They have to be transported to and from the cells by special carriers called lipoproteins.  There are several kinds, but the ones I will be focusing on are low-density lipoprotein (LDL, the so called “bad cholesterol”) and high-density lipoprotein (HDL, the “good cholesterol”).   LDL transports cholesterol to the cells, whereas HDL transports cholesterol away from the cells.  Think of LDL as a dump truck that drops garbage on the street (blocking your arteries) and HDL as the street sweeper that cleans it up.  If there are more dump trucks than street sweepers, the street will be congested.

When one has excess LDL, too much cholesterol can be deposited into the walls of the arteries.  On the other hand, insufficient HDL impairs cholesterol transport away from the walls of the arteries for disposal in the liver. Therefore too much LDL and or not enough HDL can set the stage for atherosclerosis.  This is the process in which deposits of fats, cholesterol, cellular waste products, calcium and other substances build up in the inner lining of an artery forming plaque.  Plaques can grow large enough to significantly reduce the flow of blood through an artery.  They can rupture and cause blood clots to form.  These clots can block blood flow or break off and travel to another part of the body.  If either happens and blocks a blood vessel that feeds the heart, it causes a heart attack.  If this occurs in the brain, it causes a stroke.  And if blood supply to the arms or legs is reduced, it can lead to poor circulation.

Research has shown that it is the oxidation of LDL that causes the most damage to the arteries.  Oxidation or free radical development is the process that changes the composition of this essential nutrient, turning it into a destructive compound. This oxidized LDL injuries the innermost lining of the arterial wall called the endothelium and causes inflammation.  So it is the absolute LDL level and LDL oxidation that are involved in atherosclerosis and increasing heart attack risk.

Apart from LDL-cholesterol, there are other risk factors for developing a heart attack or stroke.  They include high levels of homocysteine, fibrinogen, triglycerides (another blood fat) and C-reactive protein.  The presence of high levels of these other risk factors can result in a person suffering a heart attack or stroke, even though their cholesterol level is low.

Low Cholesterol

Studies have shown that low total cholesterol levels are associated with depression and anxiety, perhaps because low cholesterol may reduce levels of the brain chemical serotonin.  Other research suggests that low LDL levels may be associated with an increased risk of certain types of cancer.  Pregnant women who have low total cholesterol may be more likely to give birth prematurely and have babies low birth weight babies.

A low HDL level increases the risk of heart disease.  For menopausal women, a low HDL level coupled with excess weight may increase the risk of breast cancer.

What about Cholesterol and Diet?

Typically the body makes all the cholesterol it needs. The liver manufacturers about 800-1500 mg of cholesterol per day and this contributes much more to total body cholesterol than does diet.  The liver can also make cholesterol from carbohydrates, proteins or fat.

Only animal foods -egg yolks, meat (that includes mutton and oxtail!), poultry, shellfish, milk and cheese- contain cholesterol.  Foods from plants do not contain cholesterol.  (So ackee and pear do not contain cholesterol). The intake of saturated fats (found in animals and some plants) and trans fats in the diet is the main culprit in raising blood cholesterol.  Trans fat is made when manufacturers add hydrogen to vegetable oil–a process called hydrogenation; this increases the shelf life and flavor stability of foods containing these fats.  They can be found in vegetable shortenings, some margarines,  cookies,  snack foods,  and foods made with or fried in partially hydrogenated oils.

The Good News

Simple changes can reduce your bad cholesterol and increase the good.

• Maintain a level of physical activity that keeps you fit. Walk or do other activities for at least 30 minutes on most days.  If you need to lose weight, do enough activity to burn more calories than you eat every day.

• Limit your intake of foods that are high in calories and low in nutrition; especially limit foods like soft drinks and candy.  Add foods that are high in soluble fibre – whole grains, oats, legumes, fruits, vegetables, nuts, and seeds. Research suggests that the Mediterranean diet—low in saturated and trans fat, high in healthy unsaturated fats, and low in calories—reduces LDL cholesterol significantly better than other diets.   This diet is rich in vegetables, lean fish, and chicken and low in red meat.   A really low- or no-fat diet does a good job of lowering LDL , but may also reduce HDL.   Eating foods and drinks with added phytosterols (plant stanols and sterols) is another way to drop your LDL. The American Heart Association recommends 2 to 3 grams a day of plant sterols .

In addition I recommend the following supplements

• B vitamins in particular B 6,  B12,  folic acid and Niacin.  Niacin,  is particularly effective at promoting a healthy balance between LDL and HDL cholesterol.  Take a minimum of 100 to 200 mg a day.  It can cause the skin to turn red and tingly.  To counter this effect,  I tell my patients to take a baby aspirin and/or 500 mg of Vitamin C with their Niacin.

• Fish oil 1,000 to 3,000 mg daily

• Anti-oxidants. These include garlic, Vitamins A, C, E , the mineral selenium.

• Red yeast rice extract 600 to 1,200 mg a day.  Do not use this supplement if you are taking a statin (prescription medication for lowering cholesterol)

• Artichoke leaf extract.  Take 1800 mg daily

• Policosanol Take 10 mg daily

• Coenzyme Q 10 This antioxidant is essential for the production of energy in little cellular engines called mitochondria.  Statins deplete the body’s natural supply of this antioxidant.  Take 100 to 200 mg daily

DR. JACQUELINE E. CAMPBELL B.Sc. (Hons) M.Phil. (Pharmacology) M.B., B.S.

Dr. Jacqueline Elaine Campbell is a family physician whose special interests are Pharmacology, and the use of Alternative/Complementary Medicine in the treatment of diabetes and other diseases that are common in Jamaica.

She is the author of A Patient’s Guide to the Treatment of Diabetes Mellitus.