Nutrition Basics:

Fats and Oils

Some fat is essential for normal body function. Fats can have good or bad effects on health, depending on their chemistry. New research suggests that the type of fat is more important than the total amount of fat when it comes to reducing heart disease. Monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) are “good” fats that help promote heart health, and should be the main type of fats consumed. Saturated fats and trans fats (trans fatty acids) are “bad” fats that can contribute to heart disease, and should be avoided or limited.

Current dietary guidelines for heart health recommend that:

• Total fat from all fat sources should be 25 - 35% of total daily calories.
• Monounsaturated fatty acids (found in olive oil, canola oil, peanut oil, nuts, and avocados) and omega-3 polyunsaturated fatty acids (found in fish, shellfish, flaxseed, and walnuts) should be the first choice for fats.
• Omega-6 polyunsaturated faty acids (corn, safflower, sunflower, and soybean oils and nuts and seeds) are the second choice and should account for 5 - 10% of total calories as part of total fat intake. Linoleic acid, the main omega-6 fatty acid found in food, has anti-inflammatory properties. Higher intakes of omega-6 fatty acids may help lower blood pressure and reduce diabetes risk.
• Limit saturated fat (found predominantly in animal products, including meat and full fat dairy products, as well as coconut, palm oils, and cocoa butter) to less than 7% of total daily calories.
• Limit trans fats (found in stick margarine, commercial baked goods, snack and fried foods) to less than 1% of total calories.

All fats, good or bad, are high in calories compared to proteins and carbohydrates. In order to calculate daily fat intake, multiply the number of fat grams eaten by nine (one fat gram provides 9 calories, whether it's oil or fat) and divide by the number of total daily calories desired. One teaspoon of oil, butter, or other fats provides about 5 grams of fat. All fats, no matter what source they are from, add the same calories. The American Heart Association recommends that fats and oils have less than 2 grams of saturated fat per tablespoon.

Saturated fats
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Trans-fatty acids
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Try to replace saturated fats and trans fatty acids with unsaturated fats from plant and fish oils. Omega-3 fatty acids, which are found in fish and some plant sources, are a good source of unsaturated fats. Generally, two servings of fish per week provide a healthful amount of omega-3 fatty acids.

Fish oil dietary supplements are another option. Fish and fish oil supplements contain docasahexaenoic (DHA) and eicosapentaenoic (EPA) acids, which have significant benefits for the heart. Patients with heart disease, heart failure, or those who need to lower triglyceride levels may in particular benefit from fish oil supplements, provided under a doctor� ' s consultation. High amounts of fish oil supplements may cause excessive bleeding and other risks.

Omega-3 fatty acids
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Fat Substitutes. Fat substitutes added to commercial foods or used in baking, deliver some of the desirable qualities of fat, but they do not add as many calories. They cannot be eaten in unlimited amounts. They are considered most useful for helping keep down total calorie count.

• Plants substances known as sterols, and their derivatives called stanols, reduce cholesterol by blocking its absorption in the intestinal tract. Margarines containing sterols are available.
• Olestra (Olean) passes through the body without leaving behind any calories from fat. However, it can cause cramps and diarrhea, and even small amounts of olestra may deplete the body of certain vitamins and nutrients.
• Beta-glucan is a soluble fiber found in oats and barley.

A number of other fat-replacers are also available. Although studies to date have not shown any significant adverse health effects, their effect on weight control is uncertain, since many of the products containing them may be high in sugar. People who learn to cook using foods naturally lacking or low in fat eventually lose their taste for high-fat diets, something that may not be true for those using fat substitutes.

Carbohydrates, Fiber, and Sugar

Carbohydrates are either complex (as in starches) or simple (as in fruits and sugars). One gram of carbohydrates provides four calories. The current general recommendation is that carbohydrates should provide 50 - 60% of the daily caloric intake. Many studies report that people can protect their heart and circulation by eating plenty of fruits and vegetables.

Complex Carbohydrates (Fiber). Complex carbohydrates found in whole grains and vegetables are preferred over those found in starch-heavy foods, such as pastas, white-flour products, and potatoes. Most complex carbohydrates are high in fiber, which is important for health. Whole grains are extremely important for people with diabetes or at risk for it.

Complex carbohydrates
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Dietary fiber is an important component of many complex carbohydrates. It is found only in plants. Fiber cannot be digested by humans but passes through the intestines, drawing water with it, and is eliminated as part of feces content. The recommended daily intake of dietary fiber for heart protection is at least 25 grams for women and 38 grams for men. Different fiber types may have specific benefits:

• Insoluble fiber (found in wheat bran, whole grains, seeds, nuts, legumes, and fruits and vegetables) may help achieve weight loss. Consuming whole grains on a regular basis may lower the risk for heart disease and heart failure, improve factors involved with diabetes, and lower the risk for type 2 diabetes. (Wheat bran taken as a supplement has not been associated with any benefits. The whole grain may be needed for good health.) High consumption of nuts (such as almonds, macadamia, and walnuts) may be highly heart protective, independent of their fiber content.
• Soluble fiber (found in dried beans, oat bran, barley, apples, citrus fruits, and potatoes) may help achieve healthy cholesterol levels and possibly reduce blood pressure as well.
• Soluble fiber supplements, such as those that contain psyllium or glucomannan, may also be beneficial. Psyllium is taken from the husk of a seed grown in India and is very effective for lowering total and LDL cholesterol. It is found in laxatives (Metamucil), breakfast cereals, and other products. People who increase intake of soluble fiber should also drink more water to avoid constipation.

Soluble and insoluble fiber
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Simple Carbohydrates (Sugar). Doctors recommend that no more than 10% of daily calories should come from sugar. (Currently, Americans eat nearly half a pound of sugar a day on average, and sugar intake constitutes 25% of a day's calories.) Sugars are usually one of two type:

• Sucrose. Source of most dietary sugar, found in sugar cane, honey, and corn syrup.
• Fructose. Found in fruits and vegetables. Although fructose does not appear to be have any different effects in the body than sucrose, most of the fruits and vegetables that contain it are important for good health.

Simple carbohydrates
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High levels of sugar consumption -- whether fructose or sucrose -- have been associated with higher triglycerides and lower levels of HDL cholesterol, the so-called good cholesterol. The high consumption of sugar is most likely one of the factors in the current obesity epidemic. Soda, other sweetened beverages, and fruit juice are major contributors to childhood obesity.

Protein

Protein is found in animal-based products (meat, poultry, fish, and dairy) as well as vegetable sources such as beans, soy, nuts, and whole grains. In general, doctors recommend that proteins should provide 12 - 20% of daily calories. One gram of protein contains four calories. Protein is important for strong muscles and bones. The best sources of protein are fish, poultry, and soy. Restrict intake of red meat or any meat that is not lean.

Dietary Cholesterol. Animal-based protein contains dietary cholesterol. High amounts of dietary cholesterol occur in meat, whole fat dairy products, egg yolks, and shellfish. (Plant foods, such as fruits, nuts, grains, do not contain cholesterol.) The American Heart Association recommends no more than 300 mg of dietary cholesterol per day for the general population and no more than 200 mg daily for those with high cholesterol or heart disease.

Cholesterol producers
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Fish. Fish is probably the best source of protein. Evidence suggests that eating moderate amounts of fish (twice a week) may improve triglyceride and HDL levels and help lower the risks for death from heart disease, dangerous heart rhythms, blood pressure, a tendency for blood clots, and the risk for stroke.

Stroke
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The most healthy fish are oily fish, such as salmon, mackerel, trout, or sardines, which are high in omega-3 fatty acids. On average, three capsules of fish oil (preferably as supplements of DHA-EPA) are about equivalent to eating one serving of fish.

Most guidelines recommend eating fish at least twice a week. Doctors may recommend that people with heart disease or high triglyceride levels consume extra quantities or take DHA-EPA supplements.

Women of childbearing age or nursing mothers should avoid fish that contains high amounts of mercury (such as shark, swordfish, golden bass, and king mackerel) and limit intake of tuna to 6 ounces/week. They should, however, try to eat at least 12 ounces/week of a variety of lower mercury-containing fish and shellfish (such as catfish, salmon, haddock, perch, tilapia, trout, crab, shrimp, and scallops). Most doctors agree that the benefits of fish intake (especially from low-mercury fish) outweigh the potential risks.

Soy. Soy is an excellent food. It is rich in both soluble and insoluble fiber, omega-3 fatty acids, and provides all essential proteins. Soy proteins have more vitamins and minerals than meat or dairy proteins. They also contain polyunsaturated fats, which are better than the saturated fat found in meat. The best sources of soy protein are soy products (tofu, soy milk, soybeans). Soy sauce is not a good source. It contains only a trace amount of soy and is very high in sodium.

For many years, soy was promoted as a food that could help lower cholesterol and improve heart disease risk factors. But an important review of studies found that soy protein and isoflavone supplement pills do not really have any effects on cholesterol or heart disease prevention. The American Heart Association still encourages patients to include soy foods as part of an overall heart healthy diet but does not recommend using isoflavone supplements.

Meat and Poultry. For heart protection, choose lean meat. Saturated fat in meat is the primary danger to the heart. The fat content of meat varies depending on the type and cut. It is best to eat skinless chicken or turkey. The leanest cuts of pork (loin and tenderloin), veal, and beef are nearly comparable to chicken in calories and fat as well as their effect on LDL and HDL levels. However, even chicken and lean meat do not improve cholesterol levels and, in terms of heart health, fish is a more desirable choice.

Dairy Products. The best dairy choices are low-fat or fat-free products. Substituting low-fat dairy products can help lower blood pressure and lower the incidence of factors related to type 2 diabetes and heart disease (insulin resistance, high blood pressure, obesity, and unhealthy cholesterol).

Vitamins

Antioxidant Vitamins. Vitamins E and C have been studied for their health effects because they serve as antioxidants. Antioxidants are chemicals that act as scavengers of particles known as oxygen-free radicals (also sometimes called oxidants). High intake of foods rich in these vitamins (as well as other food chemicals) have been associated with many health benefits, including prevention of heart problems.

Although some older research initially observed favorable effects from vitamin E in preventing blood clots and preventing build-up of plaque on blood vessel walls, many recent studies have found no heart protection from either vitamin E or C supplements. Supplements of vitamin E, vitamin C, and beta-carotene are not recommended.

B Vitamins (Folic Acid). Deficiencies in the B vitamins folate (known also as folic acid), B6, and B12 have been associated with a higher risk for heart disease in some studies. Such deficiencies produce higher blood levels of homocysteine, an amino acid that has been associated with a higher risk for heart disease, stroke, and heart failure.

While major studies have indicated that B vitamin supplements help lower homocysteine levels, they have no effect on heart disease outcomes. Some researchers think that homocysteine may be a marker for heart disease rather than a cause of it.

Vitamin B9 source
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Vitamin B12 source
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Minerals

Potassium. A potassium-rich diet can provide a small reduction in blood pressure. Potassium-rich foods include bananas, oranges, pears, prunes, cantaloupes, tomatoes, dried peas and beans, nuts, potatoes, and avocados. Potassium supplements should not be taken by patients without checking with your doctor first. For those using potassium-sparing diuretics (such as spironolactone), have chronic kidney problems, or who take digoxin, potassium supplements may be very dangerous.

Magnesium. Some studies suggest that magnesium supplements may cause small but significant reductions in blood pressure. However, a clinically significant benefit on blood pressure has not yet been proven. The recommended daily allowance of magnesium is 320 mg. People who live in soft water areas, who use diuretics, or who have other risk factors for magnesium loss may require more dietary magnesium than others.

Calcium. Calcium regulates the tone of the smooth muscles lining blood vessels. Studies have found that people who consume enough dietary calcium on a daily basis have lower blood pressure than those who do not. The effects of extra calcium on blood pressure, however, are mixed, with some studies showing higher pressure with calcium supplementation.

Calcium source
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Salt Restriction

Some sodium (salt) is necessary for health, but the amount is vastly lower than that found in the average American diet. High salt intake is associated with high blood pressure (hypertension). Everyone should restrict their sodium intake to less than 2,300 mg (about 1 teaspoon) a day. People over age 50, or who have high blood pressure, may need to reduce sodium intake to less than 1,500 mg daily. This lowering of blood pressure may also help protect against heart failure and heart disease.

Some people (especially African-Americans, older adults, people with diabetes, and people with a family history of hypertension) are “salt sensitive,” which means their blood pressure responds much more to salt than other people. People with salt sensitivity have a higher than average risk of developing high blood pressure as well as other heart problems

Simply eliminating the use of salt at the table eating can help. But it also important to reduce or avoid processed and prepared foods that are high in sodium. Spices can be used in place of salt to enhance flavor.

Salt substitutes, such as Nusalt and Mrs. Dash, (which contain mixtures of potassium, sodium, and magnesium) are available, but they can be risky for people with kidney disease or those who take blood pressure medication that causes potassium retention. For people without risks for potassium excess, adding potassium-rich foods to a diet can help offset dietary salt intake.

Fluids

Water. People with certain medical conditions, (such as heart failure), that cause fluid retention may need to restrict their intake of water and other fluids.

Alcohol. A number of studies have found heart protection from moderate alcohol intake (one or two glasses a day). The benefits reported include higher HDL levels, blood clot prevention, and anti-inflammatory properties plus lower rates of heart failure and heart attack. Although red wine is most often cited for healthful properties, any type of alcoholic beverage appears to have similar benefit.

However, alcohol abuse can increase the risk of hypertension and many other serious problems. Men should limit their intake to an average of no more than one or two drinks a day, and women (especially those at risk for breast cancer) and lighter people should only have one drink a day. (A “drink” is equivalent to a 12-ounce bottle of beer, a 5-ounce glass of wine, or a 1.5-ounce shot of hard liquor.) Overuse of alcohol can also lead to many heart problems. Pregnant women, people who can't drink moderately, and people with liver disease should not drink at all. People who are watching their weight should be aware that alcoholic beverages are very high in calories.

Coffee and Tea. Coffee drinking is associated with small increases in blood pressure, but the risk it poses is very small in people with normal blood pressure. Moderate coffee consumption (1 - 2 cups a day) poses no heart risks and long-term coffee consumption does not appear to increase the risk for heart disease in most people, even if they consume large daily amounts.

Although both black and green tea contain caffeine, they are safe for the heart. Tea contains chemicals called flavonoids that may be heart protective.