Despite several decades in the spot light of medical and media concern, cholesterol remains one of the most contentious aspects of the factors that influence our health. Medical experts disagree about its relationship to heart disease, and the public is uncertain as to what cholesterol actually is. People often tend to confuse the two types of cholesterol - dietary cholesterol and blood or 'plasma' cholesterol. The first is contained in food, the other is essential for the body's metabolism.
WHAT IS CHOLESTEROL?
Each day the liver manufactures up to 1 g of blood cholesterol, the fat-like, waxy material that is a component of all cells. Blood cholesterol is also involved in the creation of some hormones, and helps to make vitamin D and bile acids, which aid digestion.
The major risks of heart disease caused by high levels of blood cholesterol are rooted in genetic make-up, though diet and obesity are also important factors. While there is nothing that can be done about heredity, you can change your diet.
HOW DIET CAN HELP
Reducing saturated fats has the great est effect of all dietary measures on blood cholesterol levels, lowering them by as much as 14 per cent. Recent US studies suggest that eating foods that contain soluble FIBER - such as oatmeal, baked beans, pectin-rich fruits such as grapefruit, and dried fruit - can lower cholesterol levels still further. Compounds in GARLIC also suppress cholesterol production in the liver.
The amount of cholesterol in the diet is not reflected by the amount in the blood - this is - mostly determined by the amount of saturated fat in the diet. Foods rich in cholesterol are now not thought to dramatically increase the risk of heart disease for healthy people. However, most experts agree that those with heart problems, a family history of heart disease, or high blood cholesterol levels, should limit dietary cholesterol.
High amounts of cholesterol are found in egg yolks, offal (particularly liver and brains) and in shrimps and prawns. But controversy colors the extent to which these sources - particularly eggs, which are low in saturated fats but high in cholesterol - influence cholesterol levels. While the World Health Organization argues that up to ten eggs a week will not hurt you, the British Heart Foundation believes that three to four eggs a week is the safe maximum - while its transatlantic counterpart, the American Heart Association, sets the level at three.
In fact, the average daily cholesterol intake of British males is about 390 mg daily and that of women about 290 mg - enough to raise blood cholesterol levels by about 5 per cent.
Fortunately, the body can normally iron out rises in dietary cholesterol. With most people the liver automatically manufactures less cholesterol when levels from foods in the diet become too high. Even where there is a substantial intake of fats, the average healthy person is not at risk.
Because blood is mainly composed of water - which does not blend with fat - cholesterol is transported around the body attached to specific proteins called lipoproteins. There are two types of lipoproteins; low density lipoproteins (LDL) and high density lipoproteins (HDL). LDL carry about three-quarters of the cholesterol in blood, and high LDL levels usually reflect high cholesterol levels and imply a higher risk of heart disease. High levels of HDL - which carry much less fat - signal a lower than average risk of heart disease.
THOSE MOST AT RISK
High levels of LDL tend to stem from a defect (often hereditary) in a receptor in the liver which should remove them from the blood. When this receptor does not function properly a chronic furring of the arteries called ATHEROSCLEROSIS occurs. Hormonal disorders, which may affect those with diabetes or thyroid problems, can also 'switch off' the receptors.
Because the female hormone oestrogen increases both the number and effectiveness of LDL receptors, there fore helping to keep blood cholesterol levels low, women are less prone to heart disease before the menopause. Women also tend to have higher levels of HDL, which further reduce the risks of atherosclerosis and heart disease.
Exercise often helps to lower LDL levels and raise HDL. Moderate alcohol consumption - three glasses of beer a day, or two of wine - may also increase the HDL levels in people who are not overweight. However, obesity reduces HDL levels.
Drugs used to alter the levels of the two lipoproteins tend to benefit those with high, rather than moderately raised cholesterol levels. Even when these drugs are successful, they should be accompanied by an improved diet.
.. Symptoms of a Stroke ..
If you are experiencing any of the following stroke symptoms, call your doctor or an ambulance at once. Waiting too long or not recognizing the signs could mean the difference between life and death. If you experience any of these symptoms and then feel better within 24 hours, you may have had a transient ischemic attack, or TIA. A TIA is a warning sign that a full-blown stroke is on its way. Againcall your doctor at once.
Sudden weakness or numbness of the face, arm, or leg on one side of the body
Sudden dimness or loss of vision, particularly in only one eye
Loss of speech, or trouble talking or understanding speech
Sudden, severe headaches with no apparent cause
Unexplained dizziness, unsteadiness, or sudden falls, especially along with any of the previous symptoms
(Source: "1992 Heart and Stroke Facts," by the American Heart Association.)
Eat as much like a vegetarian as possible.
Dietary cholesterol is found only in animal products; animal products also tend to be higher in fat (skim-milk products are exceptions), especially saturated fat. Foods derived from plant sources, on the other hand, contain no cholesterol and tend to be lower in fat. The fats they do contain tend to be polyunsaturated and monounsaturated, which are healthier than the saturated kind, says Peter F. Cohn, M.D., chief of cardiology at the State University of New York at Stony Brook. (The exceptions are coconut oil, palm oil, palm kernel oil, and partially hydrogenated oils, which contain higher amounts of saturated fatty acids.) Youll be doing your arteries a favor if you increase your intake of vegetable proteins, such as beans, whole grains, and tofu, and keep servings of high-fat animal products to a minimum.
Increase your carbohydrate intake.
Adding extra servings of complex carbohydrates into your diet will fill you up and make you feel more satisfied, leaving less room for fatty meats and desserts, says Cohn. Complex carbohydrates include fruits, vegetables, pasta, whole grains, and rice.
Grilling, broiling, and steaming are heart-smart ways to cook food, says Brown. Unlike frying, they require no added fat.
Skin a (dead) chicken.
The skin of chicken (and turkey, too, for that matter), is an absolute no-no for people who are watching their fat intake, according to Cohn. The skin contains high amounts of saturated fat, he says.
Skip the pastry.
One hidden source of saturated fat is pastrydonuts, Danishes, piecrust, eclairs, and so on, says Brown. These confections are often made with shortening or butter two things that should be limited by people who are working to reduce their saturated fat intake. Stick with whole-grain bread and rolls, and read labels to be sure you know whats in the package, he suggests.
Fish oil, as a cholesterol reducer, has gotten a lot of play in the media in the past few years. And it is true that the slimy stuff contains high levels of omega-3 fatty acids, substances that have been associated with lower cholesterol levels, according to Blackburn. However, the greatest benefit has been achieved in people who frequently substitute their intake of higher-fat meats with fish. Also, fish oil itself tends to be high in fat, Blackburn says. His advice is to add more servings of fish into the diet (as substitutes for some of the meat dishes) and reap the oils benefits naturally.
Go easy on yolks.
You can have all the eggs you like, as long as you leave the yolks behind. Egg yolks are more than 50 percent fat and also contain high amounts of cholesterol. Egg yolks may also be hidden inside processed foods, so be sure to read labels carefully. The AHA recom-mends limiting egg yolks to no more than three per week, including those found in processed foods or used in cooking.
Eat smaller meat portions.
One way to cut down on saturated fat without giving up steaks is to keep your portions small, says Brown. Reduce the size of the meat portions, even chicken, to about three ounces per serving, he advises. Try to have a vegetarian lunch. Then you can have six ounces at dinner. A three-ounce serving is about the size of a deck of cards, Brown says.
Give up organ meats.
Like eggs, organ meats are something best left behind as a memory of foods gone by, says Brown. Although rich in iron and protein, these meats are also tremendously high in fat and cholesterol. And remember pate is made from liver so it, too, should be restricted.
Increase your fiber intake.
Soluble fiber, the kind found in fruits and brans, has been shown to be effective in lowering cholesterol levels, says Brown. However, to exert this effect, it must be consumed in high amounts; a bowl of oatmeal a day probably wont make much difference. You have to eat about a quarter pound of oatmeal per day to get ten grams of soluble fiber a day, the amount that can lower cholesterol, he says. He recommends a daily one-teaspoon dose of a psyllium-husk powder, such as Metamucil, which provides a lot more bang for your buck. For the person whose cholesterol is still borderline high after changing their diet, psyllium may give them another eight percent to ten percent reduction in their LDL, he says. And no need to go overboard, either. More than ten grams a day wont make much more of a difference, he says. Its also prudent to increase your fiber intake gradually in order to give your system time to adjust.
Eat like the rest of the world.
Four billion of the 5.3 billion people on this earth eat 15 grams of saturated fat or less each day, says Castelli. Where do they live? Asia, Africa, and Latin America. They are the four billion people that never get atherosclerosis. We want our 250 million people to eat like those 4 billion. If we accom-plished this, we could get rid of heart attacks, stroke, and other manifestations of cardiovascular disease. We could live five years longer, which isnt much. However, we wouldnt have heart attacks in our 40s, SOs, 60s, 70s, or 80s. That is the vision for America.
Most of us are aware that smoking can cause lung cancer and raise the risk of heart attack, but few people know that smoking can actually affect your cholesterol levels, says Brown. When you stop smoking, your HDL levels rise significantly, he explains. A two-pack-a-day smoker who quits may have an eight-point rise in their HDL cholesterol.
Add exercise to your daily routine.
Studies have shown that regular aerobic exercise can boost levels of HDL, says Brown. Exercise can be very useful in reducing body weight, which can help cholesterol levels, he says. When you engage in even modest amounts of exercise, your triglycerides come down, your LDL comes down, and your HDL goes up after several months. He recom-mends 30 to 45 minutes of moderate exercise, such as walking, five days per week. It is important to accelerate your heart rate and keep it up for at least 20 minutes, he says. However, he adds, it is not necessary to do your exercise all at once. Try parking your car a quarter mile from work and walk it twice a day. Take the stairs instead of the elevator. It all adds up.
Know its never too late.
Even if youve had a heart attack or have other evidence of heart disease, changing your lifestyle can still dramatically reduce your risk of a recurrence, says Rifkind. In the past, heart specialists thought that lifestyle changes couldnt make much of a difference for people who already had heart disease. They now believe differently. We want the cholesterol to be much lower in these people than in their healthy counterparts, he says. For these people, the target levels of total serum cholesterol are between 160 and 170.
Heart attacks are the leading cause of death in the United States. In 1989 alone, says the American Heart Association (AHA); heart attacks claimed the lives of 497,850 American men and women.
What causes a heart attack? In most cases, an attack occurs when the blood supply to part of the heart muscle is severely reduced or stopped, according to the AHA. This stoppage is caused when one of the arteries that supply blood to the heart is obstructed, usually by the fatty plaques that characterize atherosclerosis, a result of coronary-artery disease.
Although its not clear where the plaques come from in each individual case, the most common causes are a blood cholesterol level thats too high, a hereditary tendency to develop atherosclerosis, and increasing age (55 percent of all heart attack victims are 65 or older, 45 percent are under 65 years of age, and 5 percent are under 40). Other factors that contribute to the likelihood that heart disease will develop are cigarette smoking, high blood pressure, and male sex (although after menopause, a womans risk rises to almost equal that of a man), according to the AHA.
You cant change your age, your gender, or your genes, but you can make positive lifestyle changes that can sharply reduce your risk of developing heart disease. Getting your blood cholesterol down to a level thats considered low risk (see Low, Borderline, High What Do the Numbers Mean?) is an important first step. The following tips are designed to help you take that step.
Adopt a new lifestyle.
Making a commitment to lowering blood cholesterol and improving your heart health requires a change of mind-set, not a temporary fad diet, according to Henry Blackburn, M.D., Mayo Professor of Public Health and a professor of medicine at the University of Minnesota in Minneapolis. You need to adopt a healthy lifestyle, a familywide lifestyle, he says. Even if one member of your family has a low risk of developing heart disease, that doesnt mean his or her risk will stay low. Our risk rises as we get older, and it takes a lifetime to establish good habits. Lifetime good habits also mean avoiding yo-yo dieting losing weight and gaining it back repeatedly. Yo-yo dieting has been shown to cause cholesterol levels to rise.
Know its never too early to act.
Although much of the emphasis on heart disease risk is placed on people with a total blood cholesterol level over 240, the numbers can be a bit misleading, says William P. Castelli, M.D., director of the Framingham Heart Study in Massachusetts, the oldest and largest heart disease study in the United States. Most heart attacks occur in people with a total cholesterol level between 150 and 250, he says. Many doctors dont understand that. That group up at the top, the highest-risk group (with cholesterol levels above 240), only produces about 20 percent of the heart attacks. Even if youre in a low or borderline group, you still need to pay attention to your lifestyle habits, he advises.
Ignore the magic bullets.
This week its rice bran, last week it was oat bran and fish oil. All were touted as the solution to your cholesterol problem. While its the American way to search for shortcuts, such an approach just doesnt cut it when youre dealing with your health, according to Basil M. Rifkind, M.D., F.C.R.P., chief of the Lipid Metabolism and Atherogenesis Branch at the National Heart, Lung, and Blood Institute in Bethesda, Maryland. We are very cautionary about these magic-bullet remedies, he says. If someones cholesterol is high, we know that it comes about by eating a bunch of foods that are higher than the optimum in fat and cholesterol. We need to address the source of the problem, instead of paying attention to garlic, fiber, or fish oil.
Stay away from saturated fats.
Many people make the mistake of believing that if their blood cholesterol level is high that its because they ate too many foods containing cholesterol. Not exactly true, says W Virgil Brown, M.D., past president of the AHA and professor of medicine and director of the Division of Arteriosclerosis and Lipid Metabolism at Emory University School of Medicine in Atlanta. The number-one cause of high serum cholesterol is eating too much saturated fat, the kind of fat that is found in full-fat dairy products and animal fat, he says. Another culprit is partially hydrogenated vegetable oil, which contains trans fatty acids, substances that increase the cholesterol-raising properties of a fat. The best rule of thumb is to stick with fats that are as liquid as possible at room temperature, according to Brown. For example, he says, if you are going to use margarine, use the most-liquid kinds, such as the tubs or squeeze bottles.
Read your meat.
The small orange labels stuck to packages of meat at the grocery store arent advertisements or promotions; theyre actually grades of meat, says Castelli. Prime, Choice, and Select are official U.S. Department of Agriculture shorthand for fatty, less fatty, and lean, he explains. Prime is about 40 percent to 45 percent fat by weight, Choice is from 30 percent to 40 percent fat, and Select, or diet lean, is from 15 percent to 20 percent fat, he says. You could have a hamburger made from Select ground beef for breakfast, lunch, and dinner and still not exceed your daily saturated fat limit, he adds.
Learn to count grams of fat.
The AHAs dietary guidelines outline the percentages of daily calories that should come from fat (see The American Heart Association Diet). However, since most package labels show grams of fat, not percentages, it can be difficult to figure out exactly what youre eating, Castelli says. Instead, he recommends counting grams of fat. How many grams of fat, and how many grams of saturated fat, can you have each day? Multiply your total number of calories per day by .30, and then divide by 9 to find the number of grams of total fat allowed. (You divide by 9 because each gram of fat provides 9 calories.) Multiply your total number of calories per day by .10 and divide by 9 to find the number of grams of saturated fat allowed each day.
If youre on a 2,000-calorie-per-day diet, you should eat no more than 22 grams of saturated fat a day, Castelli says. The average American eats twice as much.
What can you eat for 22 grams of fat? One serving of Choice beef contains from 12 to 15 grams of fat, whereas a serving of Select contains 4 to 10. One tablespoon of butter is just under seven grams, while many brands of low-fat margarine contain only one gram per tablespoon. Whole milk has a whopping five grams per cup; skim milk just one. You add it up. After all, if you choose the lower-fat versions of each item, maybe youll have enough saturated fat calories left in your daily budget to indulge in some low-fat frozen yogurt, a cup of which may contain as little as two grams of saturated fat.
Go to the extreme.
Although the AHA recom-mends deriving 30 percent or fewer of your daily calories from fat, some heart specialists believe its not only safer, but better, to go even lower than that. (The average American derives about 37 percent to 40 percent of his or her calories from fat.) Its quite appropriate for a person with a high degree of risk for heart disease to go to these sort of extremes, says Blackburn. That means reducing fats way down. You can go down even to five percent of your calories from fat without hurting yourself. Weve examined populations in Japan who consume 9 percent to 12 percent of their calories from fat and they are perfectly healthy and have very low cholesterol. Its worth the effort.