Articles about Vitamins

Vitamins: health or hype?

Every morning at 5:30 a.m. Bob Miller wakes up and heads downstairs for the morning rituals. He lets the dog out, makes coffee, glances at the newspaper, and, as he has every day for the last two years, takes his vitamins--all 16 of them.

Bob swallows 800 international units (IU) of vitamin E, 25,000 IU of beta carotene, and 1,000 milligrams of vitamin C. At lunch, the 62-year-old geologist takes more vitamin E and C, and more again at dinner. Bob, whose father and first wife died of cancer, began taking antioxidant vitamins after reading that they may help ward off the dreaded illness.

"I look at it as preventative medicine," he says. "I try to keep my automobile in repair by doing preventative maintenance, and I try to use that same philosophy on my body. Maybe it works, maybe it doesn't. But I don't have cancer."

After learning several years ago that these antioxidants don't just correct nutritional deficiencies but may actually reduce the risks of heart disease, cataracts, and certain forms of cancer, people began swallowing them in megadoses. About 100 million Americans took vitamin and mineral supplements in 1993, according to the Council for Responsible Nutrition, a trade association in Washington, D.C., that represents vitamin supplement manufacturers. Many are buying the big three--vitamin C, vitamin E, and beta carotene.

But recent studies have shown that antioxidants may not be able to reverse a lifetime of poor habits. As doctors and nutritional experts debate the preventative powers of antioxidants, confused consumers are left wondering, should we or shouldn't we?

What is an antioxidant? Antioxidants are substances that fight free radicals in our bodies. All molecules contain electrons, and these electrons normally occur in pairs. Occasionally, a free radical--an unstable molecule with an unpaired electron--shows up. Left unchecked, that molecule will steal an electron from a neighboring molecule, and the next molecule will rob from its neighbor, and so on, wreaking havoc in cells along the way.

Antioxidants combat free radicals by giving up an electron of their own, stabilizing the free radical. Some antioxidants occur naturally in the body, but research shows that additional antioxidants taken in as food or supplements help boost the good works.

What do antioxidants do? Here's a quick look at the big three and how they may benefit our bodies.

Vitamin C: Several studies have suggested that vitamin C, found in leafy greens and citrus fruits, may boost the immune system and prevent the formation of nitrosamines, which are potentially cancer-causing compounds. In some studies, people who eat foods that are rich in vitamin C have a lower risk of cancer of the stomach, cervix, and esophagus.

Vitamin E: This vitamin, found in nuts, vegetable oils, and wheat germ, may have a protective role in heart disease and cancer. Research that began in 1976 at Harvard Medical School has shown a lower risk of heart disease and stroke among participants who took vitamin E supplements. But researchers aren't certain whether people who take vitamin E supplements also do other things that reduce their chances of getting cancer or heart disease.

Taken in large amounts, vitamin E also may help prevent colon cancer, especially in women under age 65. Researchers conducting the Iowa Women's Health Study followed 35,000 women, ages 55--69, for over five years and found that the women who developed colon cancer were less likely to have taken vitamin E supplements.

Beta carotene: People who eat fruits and vegetables rich in beta carotene (which converts to vitamin A in our bodies) have a reduced risk of cancer and possibly heart disease. Beta carotene is found in many vegetables such as carrots and spinach, and eating more vegetables is thought to lower the risk of several cancers, including lung, cervix, and colon.

Do they really work? Until results from ongoing clinical trials are complete, experts will continue to disagree on the benefits of antioxidants. Some say only a healthy diet has been proven helpful with certain diseases. Others say we need supplements because we are not getting all the minerals and vitamin nutrients we need from diet alone. Besides, they say, vitamins are a cheap insurance policy for a few dollars a month that could one day pay off.

There have been several major studies on the powers of antioxidants in the body. One of the largest was published in 1993 in The Journal of the National Cancer Institute. Researchers studied 30,000 men and women in China. Some were given daily doses of vitamins, including beta carotene and vitamin E, and the others, a placebo. Those who took the supplement had a 21 percent lower death rate from stomach cancer.

Kenneth Cooper, M.D., the man credited with starting the aerobics revolution and author of Dr. Kenneth Cooper's Antioxidant Revolution (Thomas Nelson, Nashville, 1994, $22.99) is so convinced that some antioxidants can help prevent illness that he advises people to take them in doses much larger than the Recommended Dietary Allowances (RDAs). RDAs are nutritional intakes suggested by the Food and Nutrition Board of the National Academy of Sciences to maintain health in the United States.

Cooper recommends mixing up a daily "antioxidant cocktail" of 400 IU of vitamin E, 1,000 mg of vitamin C, and 25,000 IU of beta carotene.

"I reviewed over 200 articles in scientific journals before writing my book, and I was just as much a skeptic as anyone," Cooper says. "I think this is the next major breakthrough in preventative medicine. The proof is out there."

However, a high-profile study reported in April 1994 by a team of Finnish scientists has suggested that vitamin E and beta carotene may not offer protection from chronic disease after all. Among a group of 29,000 middle-aged male smokers taking either vitamin or both, the study found that there was no reduction in risk of lung cancer, and even an 18 percent increase in the disease in those taking beta carotene.

"The word that most of us use to describe the Finnish finding is 'unexpected,'" says Julie Buring, a research epidemiologist with the Harvard Medical School.

Buring adds that there are some problems with the study. Six years may not be enough time to reverse years of damage from smoking, she says. Also, because participants were smokers, there may have been other detrimental factors involved. "That study doesn't prove to me that antioxidants don't work," says Buring. "But it does raise the suspicion that the benefits may not be as great as we expected, or even that there might be some harm that was not suspected before."

In July came another disappointment: Researchers at Dartmouth University found no lower risk of potentially precancerous colon polyps in men who were given beta carotene, vitamin E, and vitamin C supplements.

Do you need supplements? Most doctors agree that the best way for your body to get vitamins and minerals is to eat a well-balanced diet that includes a minimum of five to nine servings of fruits and vegetables a day.

"Each fruit and vegetable is a storehouse of literally hundreds of antioxidants, pro-oxidants, carcinogens, anticarcinogens--all of which tend to balance each other out," says Victor Herbert, M.D., professor of medicine at Mt. Sinai School of Medicine in New York City and coauthor of The Vitamin Pushers: How the "Health Food" Industry is Selling America a Bill of Goods (Prometheus Books, New York, 1994, $26.95). Herbert argues that vitamin supplements help some people and harm others, so the bottom line is a wash.

If you are not eating a balanced diet, however, you may want to consider a supplement. Bonnie Liebman, director of nutrition for the Center for Science in the Public Interest in Washington, D.C., says sometimes it's just not realistic to say that adults are getting all the necessary nutrients from food alone. Less than 20 percent of Americans eat the recommended five servings of fruits and vegetables.

How much should you take? Whatever supplements you choose to take, be sure to do so wisely. There may be side effects if you take too large a dose.

For example, Vitamin C taken at levels greater than 1,000 mg a day may cause diarrhea. In his book, Dr. Cooper cautions against taking daily doses of vitamin E at levels above 3,200 IU, which could raise blood pressure and bring on headaches. More than 50,000 IU of beta carotene a day may turn your skin yellow.

Here are the current RDAs for adults: Vitamin C, 60 mg; vitamin E, 12 IU for women and 15 IU for men; and beta carotene/vitamin A, 4,000 IU for women and 5,000 IU for men. Fat-soluble vitamins such as vitamins A, D, and E are measured in international units. Water-soluble vitamins, such as vitamin C, are expressed in either milligrams or micrograms.

Page 2 >>>