Table 2
| Cholesterol content (mg/100g) of selected foods | |
| Food source | Cholesterol (mg/100g) |
| Egg | 504 |
| Butter | 250 |
| Shrimp | 150 |
| Mackerel | 95 |
| Herring | 85 |
| Chicken | 81 |
| Turkey | 74 |
| Lamb | 71 |
| Veal | 71 |
| Beef | 68 |
| Pork | 62 |
| Flounder | 50 |
| Milk | 15 |
A white, waxy substance, related to fats. It occurs naturally in most animal tissue. Foods particularly rich in cholesterol include eggs and offal.
Many people are surprised to learn that cholesterol has a number of essential functions in the human body: it is used in tissue repair; for strengthening cell membranes; and for the manufacture of bile salts, steroid hormones (including the sex hormones, oestrogen and testosterone), and vitamin D. There is little danger of cholesterol deficiency because it can be manufactured in the liver from fats, carbohydrates, and proteins.
The problems associated with cholesterol arise because modern diets in northern Europe and North America often result in over-production. A lot of cholesterol is not used but is deposited in the walls of blood vessels where it increases the risk of coronary heart disease and atherosclerosis. The most influential factor in raising blood cholesterol levels is eating foods high in saturated fat. Nicotine increases deposition of cholesterol in the walls of blood vessels. Hereditary factors are also important determinants of blood cholesterol levels.
A good diet can decrease blood cholesterol levels. Soluble fibre, polyunsaturated fat (especially fish fats which contain omega-3 fatty acids), and monounsaturated fat (such as olive oil) may all lower cholesterol levels. Regular aerobic exercise helps to reduce deposition of cholesterol in blood vessels.
Blood cholesterol levels vary considerably and there is no universally accepted safe level, but the following are guidelines used by most doctors:
| CHOLESTEROL LEVELS | |
|---|---|
| desirable levels | <5.2> |
| slightly raised | 5.2-6.4 mmol/l (200-250 mg/dl) |
| high | 6.5-7.8 mmol/l (251-300 mg/dl) |
| very high | >7.8 mmol/l (>300 mg/dl) |
| TYPES OF CHOLESTEROL | |
| Types | Levels |
| Total cholesterol: | |
| Desirable | <200 |
| Borderline | 200 to 240 |
| Undesirable | >240 |
| HDL cholesterol: | |
| Desirable | >45 |
| Borderline | 35 to 45 |
| Undesirable | <35 |
| LDL cholesterol: | |
| Desirable | <130 |
| Borderline | 130 to 160 |
| Undesirable | >160 |
| Ratio of total cholesterol to HDL cholesterol: | |
| Desirable | <3 |
| Borderline | 3 to 4 |
| Undesirable | >4 |
Several cholesterol test-kits can be bought over the counter. If used properly, these can give quite accurate readings, but interpreting the results is not easy, and the results may make a person unnecessarily anxious. A number of factors can affect blood cholesterol levels temporarily. Exercising or eating before the test can raise levels by more than 15 per cent. It is normal for cholesterol levels to fluctuate, so at least two tests, separated by one or two months, are needed to give a reliable average. People who are worried about their cholesterol level should have it checked properly by a doctor.
Although many people with high cholesterol levels have an increased risk of coronary heart disease, the effects of treatment are not straightforward. Treatment has been linked to increases in deaths from other causes (notably violent deaths). Cholesterol testing may be advisable for those at greatest risk (such as those with a family history of high cholesterol levels or coronary heart disease) and who are prepared to change their lifestyle. But many doctors believe that automatic screening and self-testing may turn healthy people into patients chronically anxious about their cholesterol levels. As one medical textbook states ‘It may be healthier not to know’.
Treatment
The primary goal of cholesterol treatment is to lower LDL to under 160 mg/dL in people without heart disease and who are at lower risk of developing it. The goal in people with higher risk factors for heart disease is less than 130 mg/dL. In patients who already have heart disease, the goal is under 100 mg/dL, according to FDA guidelines. Also, since low HDL levels increase the risks of heart disease, the goal of all patients is more than 35 mg/dL.
In both alternative and conventional treatment of high cholesterol, the first-line treatment options are exercise, diet, weight loss, and stopping smoking. Other alternative treatments include high doses of niacin, soy protein, garlic, algae, and the Chinese medicine supplement Cholestin (a red yeast fermented with rice).
Diet and Exercise
Since a large number of people with high cholesterol are overweight, a healthy diet and regular exercise are probably the most beneficial natural ways to control cholesterol levels. In general, the goal is to substantially reduce or eliminate foods high in animal fat. These include meat, shellfish, eggs, and dairy products. Several specific diet options are beneficial. One is the vegetarian diet. Vegetarians typically get up to 100% more fiber and up to 50% less cholesterol from food than non-vegetarians. The vegetarian low-cholesterol diet consists of at least six servings of whole grain foods, three or more servings of green leafy vegetables, two to four servings of fruit, two to four servings of legumes, and one or two servings of non-fat dairy products daily.
A second diet is the Asian diet, with brown rice being the staple. Other allowable foods include fish, vegetables such as bok choy, bean sprouts, and black beans. It allows for one weekly serving of meat and very few dairy products. The food is flavored with traditional Asian spices and condiments, such as ginger, chilies, turmeric, and soy sauce.
Another regimen is the low glycemic or diabetic diet, which can raise the HDL (good cholesterol) level by as much as 20% in three weeks. Low glycemic foods promote a slow but steady rise in blood sugar levels following a meal, which increases the level of HDL. They also lower total cholesterol and triglycerides. Low glycemic foods include certain fruits, vegetables, beans, and whole grains. Processed and refined foods and sugars should be avoided.
Exercise is an extremely important part of lowering bad cholesterol and raising good cholesterol. It should consist of 20-30 minutes of vigorous aerobic exercise at least three times a week. Exercises that cause the heart to beat faster include fast walking, bicycling, jogging, roller skating, swimming, and walking up stairs. There also are a wide selection of aerobic programs available at gyms or on videocassette.
Garlic
A number of clinical studies have indicated that garlic can offer modest reductions in cholesterol. A 1997 study by nutrition researchers at Pennsylvania State University found men who took garlic capsules for five months reduced their total cholesterol by 7% and LDL by 12%. Another study showed that seven cloves of fresh garlic a day significantly reduced LDL, as did a daily dose of four garlic extract pills. Other studies in 1997 and 1998 back up these results. However, two more recent studies have questioned the effectiveness of garlic in lowering "bad cholesterol."
Cholestin
Cholestin hit the over-the-counter market in 1997 as a cholesterol-lowering dietary supplement. It is a processed form of red yeast fermented with rice, a traditional herbal remedy used for centuries by the Chinese. Two studies released in 1998 showed Cholestin lowered LDL cholesterol by 20-30%%. It also appeared to raise HDL and lower triglyceride levels. Although the supplement contains hundreds of compounds, the major active LDL-lowering ingredient is lovastatin, a chemical also found in the prescription drug Mevacor. The FDA banned Cholestin in early 1998 but a federal district court judge lifted the ban a year later, ruling the product was a dietary supplement, not a drug. It is not fully understood how the substance works and patients may want to consult with their physician before taking Cholestin. No serious side effects have been reported, but minor side effects, including bloating and heartburn, have been reported.
Other Treatments
A study released in 1999 indicated that blue-green algae contains polyunsaturated fatty acids that lower cholesterol. The algae, known as alga Aphanizomenon flosaquae (AFA) is available as an over-the-counter dietary supplement. Niacin, also known as nicotinic acid or vitamin B3, has been shown to reduce LDL levels by 10-20%, and raise HDL levels by 15-35%. It also can reduce triglycerides. But because an extremely high dose of niacin (2-3 grams) is needed to treat cholesterol problems, it should only be taken under a doctor's supervision to monitor possible toxic side effects. Niacin also can cause flushing when taken in high doses. Soy protein with high levels of isoflavones also have been shown to reduce bad cholesterol by up to 10%. A daily diet that contains 62 mg of isoflavones in soy protein is recommended, and can be incorporated into other diet regimens, including vegetarian, Asian, and low glycemic. In 2003, research revealed that policosanol, a substance made from sugar cane wax or beeswax, lowered LDL cholesterol nearly 27% in study subjects in a Cuban study.
Allopathic Treatment
A wide variety of prescription medicines are available to treat cholesterol problems. These include statins such as Mevacor (lovastatin), Lescol (fluvastatin), Pravachol (pravastatin), Zocor (simvastatin), Baycol (cervastatin), and Lipitor (atorvastatin) to lower LDL. A group of drugs called fibric acid derivatives are used to lower triglycerides and raise HDL. These include Lopid (gemfibrozil), Atromid-S (clofibrate), and Tricor (fenofibrate).
A new class of drugs was identified late in 2001 that work differently from the statin drugs. These drugs rely on compounds that bind to a sterol that regulates protein (called SCAP) and speds up removal of cholesterol from the plasma (the fluid part of the blood.) Doctors decide which drug to use based on the severity of the cholesterol problem, side effects, and cost.
Expected Results
High cholesterol is one of the key risk factors for heart disease. Left untreated, too much bad cholesterol can clog the blood vessels, leading to chest pain (angina), blood clots, and heart attacks. Heart disease is the number one killer of men and women in the United States. By reducing LDL, people with heart disease may prevent further heart attacks and strokes, prolong and improve the quality of their lives, and slow or reverse cholesterol buildup in the arteries. In people without heart disease, lowering LDL can decrease the risk of a first heart attack or stroke.
Prevention
The best way to prevent cholesterol problems is through a combination of healthy lifestyle activities, a primarily low-fat and high-fiber diet, regular aerobic exercise, not smoking, and maintaining an optimal weight. In a small 2003 Canadian study, people who ate a low-fat vegetarian diet consisting of foods that are found to help lower cholesterol dropped their levels of LDL cholesterol as much as results from some statin drugs. But for people with high risk factors for heart disease, such as a family history of heart disease, diabetes, and being over the age of 45, these measures may not be enough to prevent the onset of high cholesterol. There are studies being done on the effectiveness of some existing anti-cholesterol drugs for controlling cholesterol levels in patients who do not meet the criteria for high cholesterol but no definitive results are available.
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