"I never get sick. I've got loads of energy," said Melissa Norris, 46, a former nurse who's studying to become an interior designer.

	Tony Tye, Post-Gazette Melissa Norris of Franklin Park swears by her supplements regimen. Click photo for larger image. Related article Alphabet soup: What all those vitamins will do

The tall, slim mother of three owes her health and vitality mostly to proper diet (she eats lots of fruits and vegetables, 80 percent of them certified organic); to exercise (she runs five miles four to five times a week); and maybe to good genes.

But Ms. Norris thinks much of the credit should go to the vitamin and mineral supplements she's been taking "on and off" for 20 years.

"I feel great," she said. "I have much more energy than when I didn't take them."

Vitamins are organic substances necessary for normal health and growth in higher forms of animal life, including humans. We must obtain the vitamins we need from food or from supplements because our bodies can't produce them.

Lack of a vitamin in our diets may lead to a deficiency disease -- this is how vitamins were discovered. In 1747, James Lind, a surgeon on a British naval ship, noticed that eating citrus fruits could prevent scurvy, which is marked by spongy gums, thin hair and poor healing of bruises.

Dr. Lind never did learn exactly what it was in citrus fruits that kept his sailors healthy, but scurvy largely disappeared when they ate limes (which is how British sailors came to be known as "Limeys.). It would be a century and a half before the nutrients that prevented scurvy and other diseases were isolated.

In 1905, English scientist William Fletcher was researching the cause of the disease beriberi, whose symptoms include pain and muscle wasting. He noticed it could be prevented by eating unpolished, rather than polished, rice. He concluded that the husk of rice must have special nutrients.

The term "vitamin" was coined in 1911 by a Polish scientist, Cashmir Funk, the discoverer of vitamin B-1. It is a compound of "vita" (meaning life) and "amine," because all vitamins were thought then to have a nitrogen-containing compound called an amine. The final e was dropped when it was learned that some vitamins contain no nitrogen.

Vitamin C, the nutrient in citrus fruits that prevents scurvy, was the first vitamin to be artificially synthesized, in 1935.

		Your minimum daily requirement The key vitamin supplement, Drs. Bonci, Istkowitz and Vactor agree, is a good multivitamin. The major commercial brands -- One a Day and Centrum, for instance -- are satisfactory, though they spend too much on advertising to suit Dr. Vactor's taste. Better quality vitamins can be purchased from health food stores or through chiropractors' offices. (Dr. Vactor sells vitamins through his practice.) In its February issue, Consumer Reports gave its seal of approval to the major brands, but warned against buying super-cheap vitamins at discount stores. Of 18 discount brands tested, "nearly half failed to contain the labeled amount of at least one nutrient, and several did not dissolve adequately," Consumer Reports said. If you decide to take a multivitamin, make sure it is age specific, Dr. Bonci said. "As you get older, your vitamin D needs go up, while your need for vitamin A and iron goes down," she said. Dr. George Obikoya, who sells vitamins online, said it is better to take them in liquid rather than pill form. But Drs. Bonci, Istkowitz and Vactor said this doesn't matter, except for people with digestive problems. -- Jack Kelly

Ms. Norris, who lives in Franklin Park, routinely takes vitamin C to ward off colds; a multivitamin; a calcium and mineral supplement to build up bones; and omega-3 fatty acid to retard aging and reduce the risk of heart disease.

When required, she takes glucosamine sulfate to relieve joint pain from running, and primrose oil and a magnesium/calcium/herbal supplement to ease premenstrual discomfort.

Ms. Norris spends about $30 a month on the vitamins she takes.

What about proper diet?

It isn't necessary for most people to take vitamin supplements if they eat properly, said Dr. Leslie Bonci, director of sports nutrition for the University of Pittsburgh Medical Center.

"With the abundance of what we have in our food supply, it's not all that difficult to get [vitamin] needs met across the board," she said. Nor are vitamins a substitute for a poor diet, she added.

Dr. Marc Istkowitz, an internist at Allegheny General Hospital, agreed.

"We recommend that people eat a healthy, balanced diet," he said.

Dr. Istkowitz said he recommends supplemental vitamins and minerals only for patients at risk for bone disease, and for women who are pregnant or contemplating pregnancy.

Dr. Bonci recommends vitamin supplements for three groups of people:

Women who are lactating or pregnant.

Chronic dieters. "If you are restricting your food intake, you are shorting nutrients."

"People who are vegetarians and are not doing it well." (Many vegetarians fail to get enough vitamin B12, she said.)

Dr. Bonci doesn't fit any of those categories, but she takes calcium and a multivitamin supplement because she travels a lot and can't count on getting all the vitamins she needs in restaurant food, she said.

"I look upon it as an insurance policy," Dr. Bonci said. "I don't look at it as replacement."

Taking vitamins is not a substitute for eating properly, she said. "A lot of people think vitamins become the magic bullet. They have a well-supplemented crappy diet.''

Dr. Raymond Vactor, a chiropractor and the co-host of a radio show on health and nutrition (Quantum Health, which airs Tuesdays at 11:00 a.m. on WKHB 620 AM), agrees with Dr. Bonci that supplements do not replace food.

But he thinks just about everyone should be taking vitamin and mineral supplements.

A survey by the National Cancer Institute indicated only 10 percent of Americans eat the five servings of fruit and vegetables each day that are considered the minimum for a healthy diet.

Even people who eat lots of fruit and vegetables may not be getting enough vitamins because chemical fertilizers and pesticides kill off nutrients; cooking and canning deplete nutrients; and, in winter, fruits and vegetables are shipped a long distance, with nutrients lost in the process, he said.

Drinking coffee, taking prescription drugs and smoking cigarettes also deplete nutrients, Dr. Vactor said.

Everyone should take a multivitamin, a vitamin C product to ward off colds, and an anti-oxidant, he said.

Many people also would benefit from taking an acidophilus product, which aids in digestion, Dr. Vactor said.

"You can eat the best foods in the world, but if you're not digesting them properly, you're not getting the full benefit from them," he said.

In addition, "every woman should be on a bone-building supplement," he said.

"I think if everybody were on those particular products, the improvement in their health would be amazing," Dr. Vactor said.

What makes sense

The Harvard School of Public Health agrees more with Dr. Vactor.

"If you eat a healthy diet, do you need to take vitamins?" the school asks on its Web site.

"Not long ago, the answer from most experts would have been a resounding 'no.' Today, though, there's good evidence that taking a daily multivitamin makes sense for most adults."

Evidence is accumulating that vitamins do more than ward off diseases of deficiency, the Harvard School of Public Health said. "Intake of several vitamins above the minimum daily requirement may prevent heart disease, cancer, osteoporosis, and other chronic diseases."

Dr. Bonci, Dr. Istkowitz and Dr. Vactor think there is little to be gained by taking megadoses of vitamins, as some health gurus recommend.

"There is no strong evidence that megadoses of any vitamin are helpful," Dr. Istkowitz said. "There's lots of research that shows no benefit, and even some research that shows harm."

For instance, vitamin A can build up in the body, and megadoses can cause kidney stones, Dr. Istkowitz said.

The Harvard School of Public Health said research into the effectiveness of megadoses of vitamin C to ward off colds has had disappointing results.

"Small trials suggest that the amount of vitamin C in a typical multivitamin taken at the start of a cold might ease symptoms, but there's no evidence that megadoses make a difference," the school said.