We all know vitamins are something essential to our body, but we may not be very clear about the exact benefits of different types of vitamins. In this article the author focuses on the benefits of vitamin E and recommends for us to take it. What are the exact benefits of vitamin E and how much should we take every day?

    Alexandra (Alex) Owens, 36, an executive in New York City, takes vitamin E every day. So does her husband, Michael, 41. Everything Alex has read about the supplement indicates it might protect against a host of illnesses.¹
     Even before reading the reports, Alex had heard convincing evidence from her grandmother, Thelma Van Arsdel, who had taken vitamin E from her early 50’s until her death at age 93. The one time Van Arsdel stopped taking it, in her late 60’s, she told Alex she felt the typical aches and pains of her age. But as soon as she began using vitamin E again, she regained her flexibility and was unusually alert and active the rest of her life. Alex and her husband hope the vitamin will keep them as healthy as it did her grandmother.
     There is good reason to believe it might. A wealth of research shows the potential benefits of this vitamin. 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（动脉硬化）, which can lead to heart attacks and strokes; possibly limit damage from cigarette smoking; boost immune response; ease arthritic（关节的）symptoms and delay the ravages (毁坏) of Alzheimer’s.²
     But don’t most of us get sufficient vitamin E from diet alone? “I used to believe that if you ate a good diet, that was enough,” says Dr. Nancy Snyderman, a California cancer surgeon. “But frankly you don’t get enough of the nutrient （营养品）.” Protective levels of this vitamin are far higher than what you typically get from foods, such as nuts and seeds, with the highest vitamin E concentrations. To consume just 100 I.U.s (international units) — the minimum dose in most supplements — you’d have to eat nearly five pounds of spinach（菠菜）or four cups of peanuts.
     If even half of the early findings about vitamin 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:
     Vitamin E Boosts Your Immune System
     According to Jeffrey Blumberg, a human nutrition researcher at Tufts University in Boston, supplementing a healthful diet with vitamin E may offer many benefits. “We think you could be safer from infectious disease—colds, flu, tuberculosis（结核病）.”
     Researchers at Tufts tested the 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.³ Each of 88 volunteers, 65 and older, was assigned to one of four groups: members of the first group got 60 I.U.s of vitamin E per day; a second group got 200 I.U.s; a third got 800 I.U.s, and the fourth got placebos（安慰剂）.
     What they discovered was startling（令人吃惊的）. 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,” Blumberg says.
     Subjects taking 200 I.U.s got a bigger immune-system boost than the ones who got only 60 I.U.s. But the 200-I.U. group also fared（进展）better than those on 800 I.U.s. Why? The researchers suspect 200 I.U.s may be the optimal（最理想的）dose for immune system benefits. It’s important to remember when taking supplements: more may not be better.
     Vitamin E Cuts Cardiac Risk
     Dr. Ishwarlal Jialal of the University of Texas South-western 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（心脏的）risk.
     For his study, he gave 21 healthy people far more than the usual dose: 1200 I.U.s per day for eight weeks. He found that vitamin E reduced oxidation（氧化） of LDL (low-density lipoprotein, the “bad” cholesterol), which helps form plaque（麻烦，困扰）in coronary arteries （冠状动脉）. In addition, he found vitamin E impaired（损害）the function of plaque-producing cells in those arteries. These findings mean that vitamin E may help prevent atherosclerosis, a type of artery hardening. Vitamin E launches “a double-pronged attack,” Jialal says. “In people at high risk for heart disease, the vitamin appears to reduce the potential for heart attacks.”
     The American Heart Association agrees. After several large studies showed dramatic cardiac benefits with vitamin E, the AHA 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.”⁴
     Vitamin E Might Fight Cancer
     When testing vitamin 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 National Cancer Institute-supported study of more than 29,000 adults in China, one group of subjects was given combinations of vitamin E, beta carotene and selenium（胡萝卜素和硒）. Among those participants, “there was a significant decrease in cancer and in mortality（死亡）from cancer,” says Dr. Omer Kucuk, professor of medicine at the Karmanos Cancer Institute at Wayne State University in Detroit.
     According to Kucuk, 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 I.U.s of the nutrient. Among those taking vitamin E instead of a placebo, the men had 32 percent fewer cases of prostate （前列腺）cancer. More impressive, there were 41 percent fewer prostate-cancer deaths.
     “We knew for a long time, in the test tube, that vitamin E prevents several types of cancer,” Kucuk says. Other studies are testing the vitamin’s effects on colon（结肠）, lung and breast cancers.
     Vitamin 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 vitamin C supplements may improve resistance to sunburn (日晒). Journalist Susan Milligan swears that dabbing（轻涂） vitamin E on blemishes（斑点） makes them disappear faster. And Dr. David Edelberg recommends that patients with gingivitis (牙龈炎) open a capsule and brush the vitamin on their gums (牙龈). However, the vitamin’s effectiveness against blemishes and gingivitis hasn’t been proved in studies.
     Even if you’re in perfect health, exercise regularly, keep stress to a 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 I.U.s are at lower risk for certain diseases,” Blumberg says. Like any supplement, vitamin E may be less safe at extremely high doses, and may throw off the balance of other nutrients in your body.⁵
     Considering the benefits of vitamin E, there’s every reason to give it a try.6 “That’s the biggest surprise,” Cotman says. “Something you buy in a drugstore for four or five dollars a bottle can do such wonderful things.”

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