Cholesterol Considerations
March 1999 -- Nutrition Notes

By: Andrea Platzman
Contributing Editor

  According to the American Heart Association (AHA), one in five Americans suffers from some form of vascular disease in which blood vessels - especially those leading to the heart, brain and legs - harden and become stiff. This disease, arteriosclerosis, is most commonly seen in the form of atherosclerosis, in which plaque builds up on arterial walls. This can clog arteries and restrict blood flow, eventually leading to a heart attack.

  Cholesterol, a fatty substance found in animal tissues, meats, dairy products, egg yolks and some oils, has been implicated in many heart problems, but it has gotten a bad rap according to Ronald Hoffman, M.D., director of the Hoffman Center, New York. "In my opinion, it is a critical ingredient for the production of sex and stress hormones and well as contributing to manufacture of bile for the breakdown of fat in the intestines. I look at homocysteine levels to determine my course of treatment."

  More than 200 studies have firmly established elevated homocysteine as a major independent risk factor and predictor not just for heart attacks, but for strokes, leg blood clots and general systemic artery damage. Without adequate vitamins - particularly B12, B6 and folic acid - to fuel the enzymatic action, homocysteine levels begin to elevate.

  The ratio between low-density lipoprotein (LDL, or "bad" cholesterol) and high-density lipoprotein (HDL, or "good" cholesterol) levels is more significant than an elevated cholesterol level.

  Many compounds can influence cholesterol levels, but it is critical to research potential drug/supplement interactions, since many can be fatal. "Supplements can have side effects; for example, if someone is taking anticoagulant therapy, taking vitamin E or gingko biloba may be a dangerous combination," states Riska Platt, M.S., R.D., spokesperson for AHA.

Bulk up with fiber

  Dietary fiber, especially soluble fiber found in foods such as oatmeal, beans and barley, appears to lower cholesterol levels. Oats have been shown to help lower cholesterol, and shiitake mushrooms have also been shown to have similar effects, says John Cardellina, Ph.D., director of botanical sciences and regulatory affairs at the Council for Responsible Nutrition in Washington, D.C.

  Rhubarb-stalk fiber may also be effective in reducing cholesterol levels. Studies have found that consuming 27 grams of the powdered form each day could lower total cholesterol levels by 8% and LDL cholesterol by 9%. Psyllium, another fiber, has been shown to prevent cholesterol absorption as well as increase fecal bulk.

Going for the garlic

  Garlic (Allium sativum) might lower blood lipid levels, inhibit platelet aggregation and decrease coagulation time, as well as lower blood pressure. Numerous clinical trials have shown that garlic lowers cholesterol and triglyceride levels. Large quantities, however, can have some side effects, including anemia and allergic reactions, as well as unusual body odor.

Vitamins and minerals

  Vitamin E slows the oxidation of low-density lipoproteins by traveling through the blood stream and attaching to LDL molecules, making them less likely to stick to artery walls. It's extremely difficult to get the recommended 100 to 400 IUs from diet alone, since the best sources are vegetable oils. For this reason, foods fortified with vitamin E are a good option. Tocotrienols, vitamin-E-like compounds found naturally in rice, oat bran and barley, are also being studied for their cholesterol-lowering effects.

  High doses - 1,000 to 3,000 mg - of nicotinic acid, a vitamin B complex also known as niacin, have been shown to lower cholesterol levels. This compound exerts dual benefits by lowering LDL while increasing HDL. However, at these high levels, it can cause serious side effects - activating peptic ulcers, impairing glucose tolerance, and damaging the liver as well as the usual flushing and fatigue. Although the time-release form of nicotinic acid is less likely to cause flushing, it can damage the liver and raise blood glucose to dangerous levels, prompting the American Medical Association to advise against its use.

Function in foods

  Functional foods also provide cholesterol-lowering opportunities. For example, plant stanol esters, found to be effective in lowering cholesterol, are added to margarine products.  Approximately 20 clinical studies have consistently shown that incorporating margarine enriched with sitostanol plant sterol ester into the diet lowers total cholesterol by 10% and LDL cholesterol by 15% in people with elevated cholesterol, says Nilo Cater, M.D., Center for Human Nutrition, University of Texas Southwestern Medical Center, Dallas.

"This cholesterol-lowering has been found even in people who are already eating the recommended low-saturated-fat, low-cholesterol diet," observes Cater.

Other cholesterol-busters

  Red-yeast rice has a 2000 year history of use, and it is even written in the Chinese Medica that it will improve blood flow. "The makers of Cholestin use this ingredient and are targeting the gray zone - people not in imminent danger," says Cardellina. In February, federal court overturned the 1998 FDA ruling that Cholestin (which contains lovastatin, the same active ingredient as Merck's Mevacor) was marketed as a drug without their approval. Lovastatin interferes with the liver's ability to manufacture cholesterol.

  To date, cholesterol claims on foods are limited to certain fibers such as oats and psyllium. Current regulations allow health-claim statements such as "soluble fiber from whole oats (or psyllium seed husks), as part of a diet low in saturated fat and cholesterol, may reduce risk of coronary heart disease."

  Currently proposed FDA labeling regulations state that a health claim of "lowers cholesterol" cannot be put on dietary supplements, since people might believe that this statement equates to treating cardiovascular disease. "All these products are designed for preventive health maintenance and could save a lot of money in healthcare costs, but the FDA does have a challenge to the way products are labeled," says Cardellina.

  Andrea Platzman is a registered dietitian who is a consultant to the food industry, and regularly writes for nutrition publications. She earned a master's degree in nutrition from New York University, and has a culinary and business background.

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