Benefits of Vitamin E

Benefits of Vitamin E
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维他命E的种种好处,你都了解吗?

Benefits of Vitamin E

A wealth of research shows the potential benefits of vitamin E. For instance, a study of 11,000 people 65 and over conducted by the National Institute on Aging found that those who took vitamin E had 41 percent less risk of dying of heart disease than those who did not. The study also found that among those taking the supplements, there was a 27 percent lower risk of death from all causes examined in the study. Other studies suggest that vitamin E may help prevent atherosclerosis, which can lead to heart attacks and strokes; possibly limit damage from cigarette smoking; boost immune response; ease arthritic symptoms and delay the ravages of Alzheimer's.

But don't most of us get sufficient vitamin E from diet alone? No, frankly we don't get enough of the nutrient. Protective levels of this vitamin are far higher than what you typically get from foods, such as nuts and seeds, with the highest E concentrations. To consume just 100 IUs — the minimum dose in most supplements — you'd have to eat nearly five pounds of spinach or four cups of peanuts.

If even half of the early findings about E are proved in continuing research, this vitamin can truly be called a health care miracle. Here's the evidence so far on how it may help you:

E Boosts Your Immune System

Researchers at Tufts tested effects of vitamin E on the immune systems of healthy older people in a four-month study, theorizing that with vitamin E they might boost those immune defenses to more effective levels. Each of 88 volunteers, 65 and older, was assigned to one of four groups: members of the first group got 60 IUs of vitamin per day; a second group got 200 IUs; a third got 800 IUs, and the fourth got placebos.

What they discovered was startling. Normally, immune cells become less efficient as we age and don't protect our bodies as much against disease. But the cells of the vitamin E groups didn't act their age. The responses of 65- and 70-year-olds looked more like those of 40-year-olds.

Subjects taking 200 IUs got bigger immune-system boost than the ones who got only 60 IUs. But the 200-IU group also fared better than those on 800 IUs. Why? The researchers suspect 200 IUs may be the optimal dose for immune system benefits. It's important to remember when taking supplements: more may not be better.

E Cuts Cardiac Risk

Dr. Ishwarlal Jialal of the University of Texas Southwestern Medical Center in Dallas has found signs of heart-protective effects in his research on vitamin E. More interesting, his results hint at reasons why vitamin E cuts cardiac risk.

For his study, he gave 21 healthy people far more than the usual dose: 1,200 IUs per day for eight weeks. He found that vitamin E reduced oxidation of LDL (low-density lipoprotein, the "bad" cholesterol), which helps form plaque in coronary arteries. In addition, he found vitamin E impaired the function of plaque-producing cells in those arteries. These findings mean that vitamin E may help prevent atherosclerosis, a type of artery hardening. In people at high risk for heart disease, the vitamin appears to reduce the potential for heart attacks.

After several large studies showed dramatic cardiac benefits with E, the American Heart Association cited the vitamin as one of the "top-ten heart and stroke research advances for 1996" that "either in supplements, or in food, may help prevent heart disease."

E Might Fight Cancer

When testing E against cancer, scientists came up with contradictory findings. Some studies found no change in the incidence of cancer. But other research recorded lower rates of cancer among people taking vitamin E.

In a study of more than 29,000 adults in China, one group of subjects was given combinations of vitamin E, beta carotene and selenium. Among those participants, there was a significant decrease in cancer and in mortality from cancer.

Scientists have long suspected that low levels of vitamin E in the body are associated with higher risk for developing cancer, while higher levels are associated with lower risk. A study of 27,000 male Finnish smokers, ages 50 to 69, showed benefits with just 50 IUs of the nutrient. Among those taking vitamin E instead of a placebo, the men had 32 percent fewer cases of prostate cancer. More impressive, there were 41 percent fewer prostate cancer deaths.

In the test tube, vitamin E prevents several types of cancer. Other studies are testing the vitamin's effects on colon, lung and breast cancers.

E May Slow Alzheimer's

In the past, Carl Cotman announced that researchers had no strategy to slow the horrible progression of Alzheimer's. Then one day in his laboratory Cotman saw under the microscope what he thought might be beginning of the answer. When he took neurons and added beta amyloid (the substance that accumulates in the brain of an Alzheimer's patient), the brain cells committed "cell suicide" by disintegration. But when vitamin E was added, the "suicide" never occurred. Cells stayed healthy. Could the vitamin's protective effect be replicated in the living brain?

In a two-year study of 341 people with moderate dementia from Alzheimer's, researchers at 23 centers sought to discover whether a Parkinson's disease drug or vitamin E would delay the onset of any of four milestones: inability to perform basic daily activities, such as bathing and dressing; severe dementia; entry into a nursing home because full-time care is necessary, or death. Those patients on placebos reached a milestone after about 14 and 1/2 months, those on vitamin E, however, reached a milestone after an average of 22 months — delaying the inevitable deterioration by more than 7 and 1/2 months.

Though hardly a cure, it is the first time the researchers have seen something slow the disease.

E's Other Benefits

This vitamin may offer a range of everyday advantages as well. A new study shows that a combination of vitamin E and C supplements may improve resistance to sunburn, and dabbing vitamin E on blemishes makes them disappear faster. It is recommended that patients with gingivitis open a capsule and dab the vitamin on their gums.

Even if you're in perfect health, exercise regularly, keep stress to minimum and eat a balanced diet, you can still benefit from vitamin E supplements, say doctors. How much should you take? Studies indicate that people who take between 100 and 400 IUs are at lower risk for certain diseases. Like any supplement, E may be less safe at extremely high doses, and may throw off the balance of other nutrients in your body.

Considering the benefits of vitamin E, there's every reason to give it a try.

AppendixIs Vitamin E Always Safe?

Supplements of this micronutrient are safe for most people (up to about 1,000 IUs) — but there are some caveats. If you take aspirin to protect against heart disease, or if you take any other prescription drug, check with your doctor. Vitamin E, like aspirin, is a blood thinner, so your physician may want to adjust how much you take. Also, because vitamin E may promote bleeding, don't take it prior to surgery or if you use anticoagulant drugs. In addition, it is suggested that you use supplements with caution if you have an overactive thyroid or rheumatic heart disease.

(Selected from Reader's Digest, August 1998, written by Anita Bartholomew)

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  • 来源:外教社 2016-06-28