Vitamins and the Heart

Article excerpt

Although minimum daily allowances for Vitamins are based on levels required to Prevent specific deficiency diseases, a growing Body of evidence indicates that higher doses of Vitamins are vital to maintaining a healthy Cardiovascular system.

According to the traditional medical viewpoint, good nutrition means eating a diet that contains enough protein, calories, vitamins, and minerals to prevent deficiency diseases. Proteins provide building blocks, calories provide energy, and vitamins are used to speed certain chemical reactions in the body. Vitamins, in particular, are only necessary in small amounts, since they are not consumed in the chemical reactions that they facilitate. Furthermore, deficiency states of different vitamins produce different clinical pictures depending on the particular reactions they are involved in. So if you eat enough vitamin A to ward off night blindness or enough vitamin C to prevent scurvy, you are well nourished.

New evidence suggests, however, that nutrients do more than prevent deficiency states; they may offer protection from chronic diseases, especially atherosclerosis, commonly known as hardening of the arteries. When the arteries supplying blood to the heart are affected, the atherosclerosis is called coronary artery disease.

Vitamin E is a fat-soluble factor discovered in 1922 to be essential for the reproduction of rats. It is naturally found in vegetable oils, wheat germ, nuts, the fats in cheese pizza, and some green vegetables. Since vitamin E is present in so many foods and is stored in the body for long periods, no simple vitamin E deficiency has been found in adults. Now, with the advent of the theory that oxidative stress (which activates cholesterol) acts as an initiator of atherosclerosis, the rote of vitamin E supplements in retarding or preventing heart disease is being seriously evaluated.

In the United States, the dietary intake of vitamin E is generally close to the recommended daily allowance of 15 units in men and 12 units in women. In most studies looking at the role of vitamin E in preventing disease, doses of 100-400 units daily were employed. Achieving this dose by dietary intake alone is impossible. Therefore, vitamin supplements in pill form are necessary.

Cholesterol, atherosclerosis, and oxidative stress

Maintaining the right balance of cholesterol in the body is essential to health. Cholesterol, which can be produced by the body, plays an essential role in moderating the fluidity of cell membranes and is the key foundation upon which several hormones are built.

In the bloodstream, cholesterol is bound to proteins in the form of particles called low-density lipoproteins (LDL) or high-density lipoproteins (HDL). LDL particles attach to the walls of arteries and are eventually incorporated within the wall as part of early atherogenesis. The HDL particles pick up cholesterol from the arterial walls and transport it to the liver for removal from the body.

An excess of LDL leads to development of atherosclerotic plaque in the arterial wall. Within limits, however, the higher the HDL, the healthier the individual, with very high levels providing added protection against heart disease. The average HDL for an adult man is 45 and for an adult, premenopausal woman, 55. Levels lower than 35 are associated with an earlier and higher incidence of coronary artery disease.

The higher the LDL, the more likely that the individual will develop early and severe coronary artery disease. Optimally, LDL levels should be less than 120. People with LDL levels greater than 180 are at risk for premature atherosclerosis.

The initial damage in atherosclerosis occurs when macrophages, or scavenger cells, enter the arterial wall, where they devour cholesterol. As they become engorged and fat, they swell the arterial lining, or endothelium, restricting the blood flow. Now called foam cells, these macrophages then break through the arterial endothelium, to intrude directly on the blood flow and act as a focus where platelets and other debris accumulate. …