Diet and Heart Disease

Heart disease is one of the leading causes of death in many industrialized nations. It develops over several decades as the coronary arteries become narrowed by cholesterol-rich deposits called plaques. This buildup, called arteriosclerosis, creates clogged arteries and can eventually lead to a heart attack. Bypass surgery is often used to treat arteriosclerosis, but less dramatic alternatives are being pursued. It is well documented that certain foods are known to provide vitamins and minerals essential to a healthy heart. Diet-based therapies proposed by Drs. Dean Ornish and Nathan Pritikin can reduce cholesterol levels ;and thus offer an alternative to bypass surgery.

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Factors Contributing to Heart disease

Also called hardening of the arteries, atherosclerosisis the thickening of the walls of the arteries, resulting in an impairment of blood flow. The impairment is caused by plaque, which is a combination of cholesterol, protein, calcium, platelets, fibrin, and other substances. There are many theories about the causes of plaque development. Diets with elevated LDL cholesterol, lowered HDL cholesterol, and high in saturated fat have drawn the most research attention. Other factors, such as arterial injury from free radical damage and nutritional deficiencies, may be equally to blame. (Free radicals are oxygen molecules that have lost an electron and are highly reactive. They damage arterial cell walls by circulating in the blood stream and grabbing electrons from other molecules, thus weakening or killing them.)

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As an emergency measure when the network of interconnecting structural fibers breaks down, the body plugs the holes in the artery walls with deposits of LDL cholesterol and other damaging materials. (The growth of these fatty nodules within the artery wall is called arteriosclerosis. These can also constrict blood flow.) The protein and LDL deposits stimulate muscle cells in the arterial wall to grow, increasing plaque size. Currently , injury to the artery is felt to be the primary cause of plaque development, while cholesterol and other plaque components are considered secondary.

Severe plaque buildup constricts blood flow, and can create problems depending on where this occurs. If it happens in the coronary arteries leading to the heart, the victim may suffer from angina or chest pain, and may eventually have a heart attack. In the arteries of the neck or brain, dizziness, senility or a stroke may be the result. Sometimes plaque deposits rupture and get into the blood stream and may clog narrowed arteries, cutting off blood flow.

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When arteries become blocked or restricted, surgeons can construct a bypass around the narrowed areas using veins taken from ant person's legs. This returns blood flow to the heart but is a temporary and partial cure. After a few years, bypasses can develop atherosclerosis and the risk of heart attack returns. Bypass surgery does not address the factors that raise cholesterol and blood pressure - risk factors for heart attacks. 

Seven factors in heart disease:

Diet Therapies

In recent years, several researchers have begun arguing that treatment for heart disease requires not just a few minor changes in diet or the administration of medication, but instead a complete lifestyle change. Here is a brief look at two of the most popular plans as put forward by Dr. Nathan Pritikin and Dr. Dean Ornish.

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Ornish Therapy - Recommendations:

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Testing and Results: 

Dr. Ornish tested 43 men and 5 women.

Control group: followed standard recommendation for heart disease patient: no smoking, moderated regular exercise, cholesterol-lowering drugs and a diet of no more than 30 percent of their calories from fat.

Treatment group: followed the full Ornish regime of no cholesterol drugs, no smoking, and practicing moderate exercise (walking for 30 minutes a day or one hour three times a week), stress management (yoga and meditation for one hour each day), and a strict vegetarian diet with no more than 10% of calories from fat. They also met twice a week for four hours of group activities such as long walks, yoga, meditation, dinner and a support group. Note: not all people in the treatment group were able to follow the program perfectly, some had trouble with yoga or meditation, thinking them silly, and others disliked the group meetings. One member died after over exercising, being highly competitive and not willingly participating in the meditation or support group. His death emphasized that stres plays a critical factor in the development of heart disease. 

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After one year:

Control group: more chest pain and increased coronary blockage.

Treatment group: reduced chest pain by 91%, reve5rsed arterial blockages by 82%. For many of the participants, blood flow to the heart doubled. (Source: Reversing Heart Disease, by Dr. Dean Ornish

Pritikin Therapy

Pritikin Therapy is a combination of diet and exercise that advocates a lifetime eating plan which, while not vegetarian, advocates a diet low in fats, cholesterol, protein and highly refined sugars and bleached white flour. It has been shown to make people feel younger, have more energy and vitality and increased sensory acuity. In addition to the diet, Pritikin advocates exercise to help the heart and circulatory system function better. 

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Food For a Healthy Heart

The following vitamins and minerals are essential for a healthy heart:

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Dietary Fats

Fat is a concentrated energy source. Having enough fat spares protein from becoming consumed when the body is making new tissue and repairing itself. Fat also helps hold body organs and nerves in position and protects them against traumatic shock and injury. Subcutaneous fat - the fat just below the skin - insulates the body and helps maintain body temperature. For the transport and absorption of fat-soluble vitamins, A, D and E, fat is essential. It also plays an important role in maintaining healthy nerve and brain tissue and cell membranes. Cholesterol is an essential fat make by the liver. The body can produce the cholesterol it needs, and will either increase or decrease production to balance cholesterol intake. Problems arise when too much is taken in and the body is overwhelmed. Cholesterol is transported through the bloodstream by lipoproteins. LDLs (low density lipoproteins) are called "bad" because they keep cholesterol circulating in the blood, causing arteries to become clogged with deposits. HGLs (high density lipoproteins) are called "good" because they move cholesterol away from the artery walls and back to the liver. 

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Dietary fats contain a combination of three types of fatty acids: saturated, monounsaturated and polyunsaturated fats. Triglycerides are fats containing varying proportions of the three groups of fatty acids. In their natural state, mono-and polyunsaturated fatty acids are generally considered not to be harmful. It is when they are altered or damaged that they can then become hazards in the blood stream. Fatty acids become damaged from processing and refining, and from the heating and frying to which they are often subjected. Saturated fats, the fat that raises blood cholesterol levels, are found in red meats, whole dairy foods, butter, margarine and tropical oils such as coconut, palm and palm kernel oil. saturated fatty acids from damaged vegetable oils and other altered/refined foods are the source of fatty deposits that can build up on the walls of the arteries and lead to heart disease. 

Monounsaturated fats are the good fats. They maintain the HDL cholesterol while lowering the LDL cholesterol levels. undamaged or unaltered polyunsaturated fats do not raise bad cholesterol levels. However, polyunsaturated fats lower HDL levels, which is not a desired action. Unfortunately, it is the type of oil found most often in processed and baked foods because it is the least expensive to use, and is found in these foods in damaged form. Canola and olive oil contain the highest proportion of monounsaturated fat compared with other cooking oils. Highest in polyunsaturated fats are safflower and corn oil. 

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Sources: While saturated fats are primarily of animal origin, with coconut oil being the exception, mono and plyunsturated oils are derived mainly from vegetables. Polyunsaturated fats and oils are the most susceptible to becoming rancid when exposed to air (oxygen) and to light, which encourages the development of free radicals. Monounsaturated oils are far more stable in the presence of light, heat and oxygen and are therefore preferred for cooking. 

One common monounsaturated oil is olive oil. Extra virgin (which refers to how it is processed) is the preferred type. Olive oil has been shown to decrease total cholesterol, LDL or "bad" cholesterol, and triglyceride levels. Olive oil does this without lowering the "good" HDL cholesterol and is considered beneficial in the fight against heart disease. 

Sources for Monounsaturated Oils:

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Sources for Polyunsaturated oils: 

Linoleic Acid (Omega 6) Oils:

Alpha-Linoleic Acid (Omega3) Oils:

Eicosapentaenoic Acid (EPA-Omeag3) Oil

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Antioxidants

Free radicals are oxygen molecules that have lost an electron and circulate through the blood stream grabbing electrons from other cells. Known as oxidating damage, grabbing electrons weakens the cells of arterial walls or can oxidize LDL (bad) cholesterol, which makes it easier for cholesterol to adhere to artery walls damaged by free radicals. In either case, impeded blood flow and clogged arteries are the result. Researchers believe oxidating damage contributes to both heart disease and cancer. 

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Antioxidants combat the destructive actions of free radicals. Antioxidants graciously donate electrons to free radicals so they do not have to steal them from the body's cells. Research evidence points to Vitamins C and E and beta-carotene, which the body converts to Vitamin A, as playing a key role in preventing oxidating damage. Vitamin E has been shown to slow the effects of aging by preventing oxidating damage to cells. One should remember that research in this field is ongoing, leading to new and sometimes conflicting results with previous findings.

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