Dietary changes that may be helpful: Eating animal foods containing saturated fat is linked to high serum cholesterol1 and heart disease. Significant amounts of animal-based saturated fat are found in beef, pork, veal, poultry (particularly in poultry skins and dark meat), cheese, butter, ice cream, and all other forms of dairy products not labeled “fat free.” Avoiding consumption of these foods reduces cholesterol and has been reported to even reverse existing heart disease. Unlike other dairy foods, skimmed milk, nonfat yogurt, and nonfat cheese are essentially fat-free. So-called “low fat” dairy products, however, are not particularly low in fat. A full 25% of calories from 2% milk come from fat. (The “2%” refers to the fraction of volume filled by fat, not the more important percent of calories coming from fat.)
In addition to large amounts of saturated fat from animal-based foods, Americans eat small amounts of saturated fat from coconut and palm oils. Palm oil has been reported to elevate cholesterol. Research regarding coconut oil is mixed, with some trials finding no link to heart disease while other research reports that coconut oil elevates serum cholesterol.
Despite the links between saturated fat intake and serum cholesterol levels, not every person responds to appropriate dietary changes with a drop in cholesterol. A subgroup of people with elevated cholesterol who have what researchers call “large LDL particles” have been reported to have no response to even dramatic reductions in dietary fat. This phenomenon is not understood. People who significantly reduce intake of animal fats for several months and see no reduction in cholesterol levels should discuss other approaches to lowering cholesterol with a cardiologist and a nutritionally oriented doctor.
Yogurt and other fermented milk products have been reported to lower cholesterol in some but not all research. Until more is known, it makes sense for people with elevated cholesterol who consume these foods to select nonfat varieties.
Eating fish has been reported to increase HDL cholesterol and is linked to a reduced risk of heart disease in most but not all studies. Fish contains very little saturated fat, and fish oil contains EPA and DHA, omega-3 oils that appear to protect against heart disease.
Vegetarians have lower cholesterol and less heart disease than meat eaters, in part because they avoid animal fat. Vegans (people who eat no meat, dairy, or eggs) have the lowest cholesterol levels, and going on such a diet has reversed heart disease.
Dietary cholesterol: Most dietary cholesterol comes from egg yolks. Eating eggs increased serum cholesterol in most studies. However, eating eggs does not increase serum cholesterol as much as eating foods high in saturated fat, and eating eggs may not increase serum cholesterol at all if the overall diet is low in fat.
Egg consumption does not appear to be totally safe, however, even for people consuming a low fat diet. When cholesterol from eggs is cooked or exposed to air, it oxidizes. Oxidized cholesterol is linked to increased risk of heart disease. Eating eggs also makes LDL cholesterol more susceptible to damage, a change linked to heart disease. Moreover, egg eaters are more likely to die from heart disease even when serum cholesterol levels are not elevated. Therefore, the idea that egg consumption is unrelated to heart disease, a position taken by some doctors of natural medicine, is not supported by most scientific evidence.
Fiber: Soluble fiber from beans, oats, psyllium seed, and fruit pectin has lowered cholesterol levels in most trials. Doctors of natural medicine often recommend that people with elevated cholesterol eat more of these high soluble fiber foods. However, even grain fiber (which contains insoluble fiber and does not lower cholesterol) has been linked to protection against heart disease, though the reason for the protection remains unclear. It makes sense for people wishing to lower cholesterol levels and reduce their risk of heart disease to consume more of all types of fiber.
Flaxseed, like other good sources of soluble fiber, has been reported to lower cholesterol. A recent study found that partially defatted flaxseed containing 20 grams of fiber per day significantly lowered LDL cholesterol, suggesting that the cholesterol-lowering component in flaxseed is likely to be the fiber in this product and not the oil removed from it. However, researchers and nutritionally oriented doctors are also interested in alpha-linolenic acid (ALA)–the special omega-3 oil found primarily in whole flaxseed and flaxseed oil. ALA is a precursor to EPA, a fish oil believed to protect against heart disease. To a limited extent, ALA can convert to EPA in the body. However, ALA is not the same as EPA or DHA, and has been reported to not have the same effects on the cardiovascular system. For example, EPA and DHA lower serum triglyceride levels (a risk factor for heart disease) but ALA does not. Moreover, preliminary research on the effects of ALA from flaxseed has produced results that appear somewhat contradictory. For example, ALA has improved parameters of arterial health that should protect people from heart disease, yet other data have implicated ALA as causing oxidation of LDL cholesterol. Oxidation of LDL cholesterol is believed to be a precursor to atherosclerosis and heart disease. As a result of these preliminary disparate findings, it makes sense for people concerned about heart disease and attempting to lower their cholesterol to consider using partially defatted flaxseed as opposed to whole flaxseed or flaxseed oil until more is known.
Soy: Tofu, tempeh, miso, and some protein powders in health food stores are derived from soybeans. A meta-analysis of many studies has proven that soy protein reduces both total and LDL cholesterol. Isoflavones from soy beans may also have this effect. Trials showing statistically significant reductions in cholesterol have generally used more than grams per day of soy protein.
Sugar: Eating sugar has been reported to reduce protective HDL cholesterol and increases other risk factors linked to heart disease. However, higher sugar intake has been associated with only slightly higher risks of heart disease in most reports. Although the exact relationship between sugar and heart disease remains somewhat unclear, many nutritionally oriented doctors recommend that people with high cholesterol reduce their sugar intake.
Coffee: Drinking boiled or French press coffee increases cholesterol levels. Modern paper coffee filters trap the offending chemicals and keep them from entering the cup. Therefore, drinking paper filtered coffee generally does not increase cholesterol levels. However, paper-filtered coffee does appear to significantly increase homocysteine—another risk factor for heart disease. The effects of decaffeinated coffee on cholesterol levels remain in debate.
Alcohol: Moderate drinking (one to two drinks per day) increases protective HDL cholesterol. This effect happens equally with different kinds of alcohol containing beverages. Alcohol also acts as a blood thinner, an effect that might lower heart disease. However, alcohol consumption can cause liver disease, cancer, high blood pressure, alcoholism, and, at high intake, an increased risk of heart disease. As a result, many doctors of natural medicine never recommend alcohol, even for people with high cholesterol. Nevertheless, those who have one to two drinks per day have been reported to live longer and are clearly less likely to have heart disease. Therefore, some people at very high risk of heart disease who are not alcoholics, have healthy livers and normal blood pressure, and are not at an especially high risk for cancer, may benefit from light drinking. In deciding whether light drinking might do more good than harm, people with high cholesterol should consult a nutritionally oriented doctor.
Olive oil: Olive oil lowers LDL cholesterol, especially when the olive oil replaces saturated fat in the diet. People from countries that use significant amounts of olive oil appear to be at low risk for heart disease. Authors of extremely low-fat diet approaches to heart disease recommending avoidance of olive oil are therefore not basing that decision of sound science. Although olive oil is clearly safe for people with elevated cholesterol, as with any fat or oil it very caloric, so its use should be limited in people who are overweight.
Trans Fatty Acids: Trans fatty acids (TFAs) are found in many processed foods containing hydrogenated oils. The highest levels of TFAs occur in margarine. Margarine consumption is linked to increased risk of heart disease. Eating TFAs increases the ratio of LDL-to-HDL. Margarine and other processed foods containing partially hydrogenated oils should be avoided.
Garlic: Garlic is available as a food, in powder as a spice, and as a supplement. Eating garlic helps lower cholesterol in some research, though more recently, several double blind studies have not found garlic to be effective. Some of the negative reports have been criticized for flaws in their design. Nonetheless, the relationship between garlic and cholesterol lowering is no longer clear. However, garlic is known to act as a blood thinner and may reduce other risk factors for heart disease. For these reasons, doctors of natural medicine typically recommend eating garlic as food, taking 900 mg of garlic powder from capsules, or using a tincture of 2–4 ml taken three times daily.
Number and size of meals: The practice of eating many small meals rather than three large ones is sometimes called “grazing.” When people eat more small meals, serum cholesterol levels fall compared with the effect of eating the same food in three big meals. People with elevated cholesterol levels should probably avoid very large meals and eat more frequent but smaller meals.
Lifestyle changes that may be helpful: Exercise increases protective HDL cholesterol, an effect that occurs even from walking. People who excercise have a relatively low risk of heart disease. People over forty years of age or who have heart disease should talk with their doctor before starting an exercise program; overdoing it can actually trigger heart attacks.
Obesity increases the risk of heart disease, in part because weight gain lowers HDL cholesterol. Weight loss increases HDL and reduces triglycerides, another risk factor for heart disease.
Smoking is linked to a lowered level of HDL cholesterol and is also known to cause heart disease. Quitting smoking reduces the risk of having a heart attack.