- The Washington Times - Sunday, February 4, 2001

Many Americans consume too much sugar, salt and fat and not enough fruits, vegetables and whole grains. To make up for the deficit, about 40 percent of adults take multivitamins, the U.S. Department of Agriculture estimates.

In the long run, popping a pill might help protect against certain diseases and lower the risk of some disorders, such as birth defects. However, it should supplement, not substitute for, a healthy diet, says Dr. Joanna Dwyer, professor of medicine at Tufts University School of Nutrition in Boston.

"I like to think of nutrition as a foundation for a house," Dr. Dwyer says. "You should start with fortified foods and build from there. Vitamins are a good idea, but I wouldn't want to build a foundation on them."

Ruth Kava, director of nutrition for the American Council on Science and Health, a consumer science organization, says the vitamins and minerals that come from foods are a complex mixture, one that makes it hard to pinpoint exactly where the benefits come from.

"Vitamins are essential," she says. "We have known that for 50 years. If your diet is not providing enough vitamins, it can be supplemented. But we tend to try and oversimplify things. When we eat foods, we are getting an incredible mixture of vitamins and minerals. The phytochemicals that are found in plants really play a part in supporting good health.

"Taking vitamin supplements is sort of a magic-bullet theory that goes back to the early days of nutrition, when certain vitamins such as niacin to cure pellagra helped eradicate debilitating disease," Ms. Kava says. "People still have an 'if a little is good, then more is better' mentality, but whether we need the extra insurance is debatable."

Still, there are several subgroups that could benefit from taking a daily multivitamin, Ms. Kava says. Children's vitamins are a good idea, especially if a child is a picky eater, she says.

"Pediatricians are pretty aware of nutritional needs," Ms. Kava says, "but it is more important that people look at the overall diet."

Adolescents could benefit from taking children's vitamins through puberty, when they are growing rapidly and have greater nutritional needs than adults, she says.

The elderly are another group that should take a daily supplement, Ms. Kava says. Older people commonly do not eat right because of a number of factors, including depression, loss of appetite and ill-fitting dentures, she says.

In addition, the elderly tend to lack vitamin D because they are not drinking milk From page D1

or getting enough sunlight, she says. The skin's ability to synthesize vitamin D from sunlight also declines with age. Vitamin D is crucial in the absorption of calcium, which protects the body against osteoporosis.

"I advise elderly patients to talk to their physician," Ms. Kava says. "If they are not getting out in the sun much, they need to get supplemental vitamin D. To prevent osteoporosis, they need to start thinking about this before it is too late."

Many middle-aged and older people don't produce enough stomach acid to absorb vitamin B12 properly from food. B12 is essential for maintaining neurotransmitters in the brain. Getting supplemental B12, either in pill form or in enriched cereal, can allay symptoms such as mental confusion, says Barbara Gollman, a registered dietitian in Dallas and a spokeswoman for the American Dietetic Association.

Women who are pregnant or likely to become pregnant also should pay particular attention to their diet, Ms. Kava says. Several studies have shown that getting 400 micrograms of folic acid a day can dramatically decrease the risk of neural-tube defects such as spina bifida, she says.

"So many pregnancies are unplanned," Ms. Kava says. "If a woman is potentially capable of getting pregnant, then she should pay attention. A multivitamin should provide enough folate, but it is also in orange juice and enriched grains and cereals."

Stock up on calcium, iron

Calcium and iron are two essential minerals that many people don't get enough of, Ms. Kava says. They are also two minerals that are hard to cram into one multivitamin pill, she says.

"Multivitamins don't have that much calcium because it is a rather dense substance," Ms. Kava says. "For women in their 30s, particularly if they don't eat a lot of dairy products, it might not be a bad idea to take additional calcium."

Says Dr. Dwyer: "You have to look at a multivitamin to see what it has in it. A lot of people think a vitamin has calcium in it, but what it often has is just a dusting of it. Most multivitamins do not have a heck of a lot of calcium."

A multivitamin, which typically contains about 45 percent of the recommended daily allowance of calcium (about 450 milligrams), may help fill in the gaps for someone who eats a lot of dairy products or fortified foods.

For others, a supplement may be necessary to meet the National Academy of Science's recommendation of 1,000 milligrams (up to age 50) to 1,200 milligrams (for men older than 50, teen-agers and post-menopausal women who take bone-bolstering drugs) to 1,500 milligrams (other post-menopausal women and everyone older than 65).

A calcium deficiency could result in osteoporosis, the thinning of the bones that affects more than 28 million Americans, 80 percent of whom are women. Osteoporosis, which typically occurs after age 50, is responsible for 1.5 million bone fractures annually, according to the National Osteoporosis Foundation.

Iron is needed for normal red blood cell growth and intellectual development. It commonly is found in red meat and green, leafy vegetables. Most people who take a multivitamin probably are getting enough, Ms. Kava says. However, people who suffer from anemia or women who have exceptionally heavy periods may benefit from taking supplemental iron, she says.

It is important not to get too much iron, she adds. A genetic disorder called hemochromatosis causes iron to build up in the blood. It affects roughly one in 250 people. High levels of iron may lead to heart and kidney damage, Ms. Kava says.

Anti-oxidants for anti-aging

It is worth checking the label of a multivitamin to see its levels of vitamins E and C, which are anti-oxidants, says Melanie Polk, director of nutrition for the American Institute for Cancer Research.

Anti-oxidants protect the body's cells from damage from free radicals oxygen-depleting molecules that are a factor in age-related ailments such as heart disease, cancer and arthritis.

"Free radicals can inflict damage on healthy cells," Ms. Polk says. "They are implicated in many diseases, but anti-oxidants try to turn that process around."

It is important to fight the free radicals with a healthy diet first, then boost it with supplements, she says.

"There are many studies pointing to the fact that nutrients work as a team," Ms. Polk says. "The most important thing to focus on is getting anti-oxidants from a large variety of fruits and vegetables."

Great sources of vitamin C include citrus fruits, broccoli and strawberries, she says.

Vitamin E is a more difficult nutrient to stock up on, but it can be found in egg yolks, salmon, nuts, seeds and vegetable oils as well as some fortified fruit juices, Ms. Polk says.

Most multivitamins contain 30 to 60 international units (IU), which is the recommended daily value of vitamin E, but far less than the higher doses needed for disease-fighting protection.

Those who take supplemental vitamin E commonly take 100 to 400 IU daily, Ms. Polk says. Some studies have shown that 800 IU can fight cancers of the colon, lungs and esophagus, she says.

The dosage of vitamin C as an anti-oxidant varies, but many experts think 500 milligrams daily will provide benefits. A recent study conducted at the University of California at Los Angeles of 11,000 adults ages 25 to 75 found that a daily intake of 300 milligrams of vitamin C from food and supplements may increase life expectancy by six years.

However, Ms. Kava warns consumers to weigh the results of vitamin studies carefully because the evidence is changing rapidly.

"One study will find an effect, and one will not," she says. "The nature of the effects in some studies is likely to be small. Also, it is notoriously difficult to ascertain what people are eating. These studies depend on people keeping track of what they eat, and most people's knowledge of food portions is pretty poor. Their ability to recall can affect analysis."

Ms. Kava also warns people to stay within recommended dosage ranges when adding supplemental vitamins to their diet. Depending on the person and the vitamin, mega-doses can have side effects ranging from stomach upset to liver damage.

"Vitamins are natural and essential," she says, "but there seems to be a feeling that more is better, which it is not. Taking the appropriate recommended daily allowance for your age and gender is not going to be harmful.

"The whole subject is paradoxical," Ms. Kava says. "The people who take vitamins are usually the same people who are already paying attention to what they are eating."

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