Today, the buzzwords for selling vitamins have been modernized—though vitamins themselves, and the human body's limited need for them, have remained the same. A recent trend is to push vitamins for the relief of "stress." Almost everyone, of course, experiences stress. If it follows that almost everyone needs vitamin supplements, commercial logic is satisfied—if not the scientific method.

In 1985, the U.S. Food and Drug Administration (FDA) and the Pharmaceutical Advertising Council began a major campaign of public-service ads attacking quackery and encouraging people to ask their physician or pharmacist about claims that seem too good to be true. Curious about what advice pharmacists give their customers about vitamins, CU sent reporters, posing as customers, to 30 pharmacies in Pennsylvania, Missouri, and California.

Our customers told the pharmacists that they'd been feeling nervous or tired lately, and asked whether a vitamin would help. In fact, neither nervousness nor fatigue calls for vitamin supplementation. But most of the 30 pharmacists seemed more than willing to sell vitamin pills for those purposes. Only nine mentioned the possibility of seeing a physician.

Pharmacists are only one part of the picture. Drug-company advertising is another big part. Pushed by the ads, the public has developed quite an appetite for vitamin pills—as well as for many other types of "dietary supplements". Surveys suggest that about half of all Americans take a vitamin pill either regularly or occasionally—and some people take a handful or more every day.

Most vitamin users, concerned that their diet may not be adequate, take their daily doses as "insurance" against deficiency. Others—operating on the dangerously mistaken theory that if some is good, more must be better—hope that the products will provide extra energy, prevent or cure disease, protect against stress, or enhance athletic ability.

What Vitamins Are and How Much You Really Need

A vitamin is an organic substance required to promote one or more essential biochemical reactions within living cells. Unlike foods, vitamins are needed only in tiny amounts and are not a source of energy (calories). For a substance to qualify as a vitamin, its absence must cause a specific deficiency disease that is cured when the substance is resupplied. (Lack of vitamin C, for example, causes scurvy, which can be cured with vitamin C.)

There are 13 known vitamins required by humans. Four are fat-soluble (A, D, E, and K), and nine are water-soluble (C and the eight "B-complex" vitamins—thiamin, riboflavin, niacin, B6, folic acid, B12, pantothenic acid, and biotin). Do any more remain to be discovered? Probably not, since patients have survived for years on intravenous feedings fortified with only these vitamins. Hucksters continue to tout non-vitamin substances such as P, B15, and B17 as vitamins, but they are not and never will be.

The Food and Nutrition Board of the National Academy of Sciences/ National Research Council publishes guidelines known as the Recommended Dietary Allowances (RDAs) for essential nutrients—protein, carbohydrates, fat, minerals, and vitamins. The RDAs are defined as "the levels of intake of essential nutrients considered adequate to meet the known nutritional needs of practically all healthy persons."

These are not "minimums" or "requirements." The level for each nutrient is deliberately set higher than most people need. The RDA for each vitamin is usually derived by estimating the range of normal human needs, selecting the number at the high end of that range, and adding a safety factor. The values vary somewhat by age and sex, and are increased for women during pregnancy and breast-feeding.

For three vitamins—K, pantothenic acid, and biotin—the Food and Nutrition Board has published "estimated safe and adequate intakes" rather than RDAs. This was done because part of people's need for those vitamins is supplied by bacteria within the intestines; how much must come from food is not known.

The FDA took the National Research Council's figures and simplified them to create the U.S. Recommended Daily Allowances (U.S. RDAs), which you see on many food labels. U.S. RDAs generally represent the highest level of the National Research Council's RDAs for each nutrient. Therefore, few if any people need more than the U.S. RDAs. Most people can do just fine on less. (In our discussion, RDA refers to the National Research Council's Recommended Dietary Allowances.)

False Alarms About Nutritional Deficiencies

Many vitamin enthusiasts suggest that everyone should take supplements to be sure of getting enough. They say, for example, that "eating on the run" and "overprocessing" of foods place the typical American in danger of deficiency. Some also speak of "soil depletion" and dieting as reasons why people need vitamin supplements.

Such arguments amount to false alarms.

It's true that many Americans commonly eat on the run, skip entire meals, and watch their weight. But it's unlikely that those habits are breeding vitamin deficiencies.

Fast-food meals, for instance, can be reasonably nutritious, especially if you patronize the salad bar. The main problem with fast food is not what's missing but what's present—a lot of calories, sodium, and fat.

As for skipping meals, many people do, but those who eat only one or two meals daily during the week usually more than make up for any deficits with snacks and with increased variety and abundance on weekends.

Dieting should be done sensibly, of course. But only prolonged or highly unbalanced diets (such as very low calorie diets or macrobiotic diets) could create a risk of vitamin deficiency.

The argument about "overprocessing" of foods oversimplifies a complex issue. Processing can remove some vitamins and other nutrients, but it can also restore them or add missing ones.

Our consultants scoff at the idea that depleted soil robs the American diet of vitamins. A plant's mineral content may be influenced somewhat by soil composition, but its vitamin content is largely determined by the plant's heredity. A carrot grown in depleted soil, for instance, may be stunted—but its vitamin A content (per unit weight) will be the same as if it had been grown in enriched soil.

Finally, some vitamins are lost in cooking. But losses of that sort are usually only partial, and are compensated for by including uncooked fruits and vegetables in your diet.

The suggestion to buy "nutrition insurance" in pill form can be very appealing, and vitamin manufacturers have run ad campaigns to promote use of their products for that purpose.

But nutrition authorities question the need for such supplements. According to Victor Herbert, professor of medicine at Mount Sinai School of Medicine in New York City, "Vitamin pushers use deception by omission. They list all the terrible things that can happen if your diet is lacking. But they never tell you that vitamin deficiency is rare unless a person's diet is extremely unbalanced. Most important, they never tell how to measure whether or not your diet is adequate. If they did, they'd lose customers. Determining dietary adequacy is actually quite easy."

You can get an adequate amount of all essential nutrients by planning your meals to include what nutritionists call the Basic Four Food Groups. Your average daily intake should include:

• Four servings of vegetables, fruits, and fruit juices, at least one of which should be fresh.
• Four servings of grain and cereal products (including cereals, breads, rice, macaroni, and the like).
• Two to four servings of meats or alternatives such as fish, poultry, eggs, or beans.
• Two to four servings of milk or dairy products.

Because foods within each group differ in nutrient content, choosing a variety within each group is important. Adhering to the recommended number of servings, with reasonable portion sizes, would provide about 1200 calories and sufficient amounts of all essential nutrients. Since most people eat more than that, it should be clear that eating a wide variety of foods from the Basic Four will easily provide the nutrients you need. Further, though some advocates would lead you to believe otherwise, a few days without one vitamin or another will do you no real harm.

Hype About Stress

If the "nutrition insurance" appeal is old news, the new ploy in selling vitamins is to offer you protection against stress. Typical "stress formula" vitamin products contain 10 or more times the RDA for vitamin C and for several of the B vitamins. While some vitamin promoters refer only to physical stresses, others include mental stress, overwork, and the like. Some make no health claims at all, but rely on the word stress in the product's name to sell it.

According to Lederle Laboratories, makers of Stresstabs 600, the concept of high-dosage stress vitamins is based on a 1952 National Research Council report that recommended extra vitamins for people suffering from stresses such as general surgery, serious burns, and major fractures.

However, the report explicitly stated that "in minor illnesses or injury where the expected duration of the disease is less than 10 days and when the patient is essentially ambulatory and is eating his diet ... a good diet will supply the Recommended Dietary Allowances of all nutrients."

Nutrition experts advise that although vitamin needs may rise with certain physical conditions, they seldom rise above the Recommended Dietary Allowances—and are easily met by proper eating. Someone who is under enough stress to incur vitamin deficiency would probably be sick enough to be in a hospital. But ads for "stress vitamins" have generally been aimed at well-nourished members of the general public.

No evidence exists that emotional stress increases the body's need for vitamins.

Hype for Athletes and Smokers

Athletes, from the professional to the weekend jogger, may be tempted to pop vitamin pills to achieve better performance or to replenish vitamins lost through vigorous activity.

It is true that strenuous exercise increases the need for calories, water, and a few nutrients. However, vitamin needs are unlikely to rise above the RDA amounts available from a balanced diet. The notion that extra vitamins are useful to athletes is also tied to the idea that extra vitamins provide extra energy—which is untrue. Energy comes from the calories in food, and vitamins have no caloric value.

A cascade of advertising hypes vitamins for athletes. Revco's Competition Plus—"for extra effort sports"—have claimed to "meet the special nutritional needs of sports active people."

Smokers are known to have lower blood levels of vitamin C than do nonsmokers, which has led some promoters to suggest that smokers should take extra vitamin C. But according to Victor Herbert, "There is no credible evidence that smokers need more than RDA amounts of vitamin C. The 1980 RDA amounts are at least four times as much as a normal person would ever need in a day."

Alfred E. Harper, professor of biochemistry and nutrition sciences at the University of Wisconsin, who chaired the 1974 National Research Council RDA Committee, says, "Since most subjects used in the major experiments that served as the basis for present vitamin C allowances were smokers, the suggestion that smokers need high doses of vitamin C seems incongruous. If anything, it would seem much more appropriate to suggest that nonsmokers need less."

Other Popular Vitamin Myths

Vitamin C and Colds Proponents of vitamin C—most notably the chemist and Nobel laureate Linus Pauling—claim that it can help prevent colds in daily doses of 1000 milligrams or more. But at least 16 double-blind studies over the past decade have found no such benefit.

The classic series of studies was conducted by researchers at the University of Toronto. They concluded that vitamin C did not prevent colds at all, but did help to reduce slightly the severity of certain cold symptoms. This mild benefit was achieved with a daily dose of 250 milligrams (about the amount in two 8-ounce glasses of orange juice). Higher doses provided no extra benefit. Indeed, the researchers eventually concluded that only 120 milligrams daily was enough.

Vitamin C and Cancer Pauling and some others also believe that massive doses of vitamin C can prolong the life of cancer patients. This claim is based on a study he reported with Ewan Cameron, a Scottish physician. However, researchers who analyzed the report concluded that the study was not properly designed.

The Mayo Clinic has conducted two clinical trials to test the effectiveness of vitamin C and cancer, each involving 100 or more patients in the advanced stage of the disease. Half the patients received vitamin C, half a placebo. The researchers found no differences in survival time, appetite, severity of pain, weight loss, or amount of nausea and vomiting.

Vitamin E and Breast Lumps Several years ago, preliminary studies by Robert London, M.D., and colleagues at Sinai Hospital of Baltimore suggested that vitamin E supplements might help women with mammary dysplasia (also called benign fibrocystic disease of the breast). But two well-designed, double-blind studies reported in 1985—including one by Dr. London's team—found no significant benefit.

B6 for Premenstrual Syndrome High dosages of vitamin B6 have been widely advanced as a treatment for premenstrual syndrome. The evidence supporting this practice is thin—mixed results in small scale studies. Since most water-soluble vitamins are relatively safe in large doses (in contrast to fat-soluble vitamins, which are not), some physicians felt comfortable in recommending B6 in the range of 200 to 800 milligrams daily. (That dose is 100 to 400 times the RDA.)

In recent years, however, physicians have reported seeing damage to the nervous system in individuals who took 500-milligram doses of B6, and in one person whose reported intake was 200 milligrams a day for three years. Their symptoms, which resembled those of multiple sclerosis, included numbness and tingling of the hands, difficulty in walking, and the sensation of electric shocks shooting down the spine. In light of these cases, we advise against megadoses of vitamin B6. CU's medical consultants take a dim view of megadose B6 therapy because of possible peripheral nerve toxicity.

Genuine Nutritional Shortages

Although vitamin deficiencies are rare among people who eat a reasonably varied diet, a fair number of Americans may need more of certain minerals. Some people—especially women—should pay special attention to these three:

• Calcium deserves particular attention because inadequate calcium intake is a factor in the development of osteoporosis, or thinning of the bones, especially in women. Those who like milk, cheese, and other dairy products may get what they need from diet alone. But those consuming little calcium-rich food should seek advice on supplementation from a physician or registered dietician.
• Iron is needed to make hemoglobin, the component in red blood cells that carries oxygen to the tissues. Lack of sufficient iron causes iron-deficiency anemia. Women who are pregnant or who menstruate heavily should be checked by a physician to be sure they are not anemic and for advice on possible iron supplements.
• Fluoride intake throughout childhood helps build decay-resistant teeth. The most efficient, economical way to get it is through fluoridated water. Children who grow up in nonfluoridated communities should take supplementary fluoride (by prescription) from birth through age 12.

Dangers of Excess

Fat-soluble vitamins are not excreted efficiently. They are generally stored in the body until they can be used up, and thus can accumulate to toxic levels. For example, prolonged excessive intake of vitamin A can cause headache, increased pressure on the brain, bone pain, and damage to the liver. Excessive vitamin D can cause kidney stones and eventual kidney damage.

Though water-soluble vitamins are generally excreted in the urine when taken in excess, some of them can cause trouble. There's the risk of permanent damage to the nervous system resulting from sustained high doses of vitamin B6, mentioned above. Large doses of niacin can cause severe flushes, skin rash, and abnormal liver-function tests. And high doses of vitamin C can cause diarrhea.

Reported cases of actual vitamin toxicity are uncommon. But they are particularly sad because most people who get into trouble with vitamins have essentially poisoned themselves in the pursuit of health.

Recommendations

The best way to get vitamins is from foods in a balanced diet. Vitamin supplementation may be appropriate for children up to two years, for older children who have poor eating habits, for some people on prolonged weight-reduction programs, for pregnant women, for strict vegetarians (those who avoid eggs and milk as well as meat), and for people with certain illnesses, as directed by a physician.

Rather than taking vitamins for "insurance," evaluate your diet to determine whether you are eating a variety of foods from the Basic Four groups. If you have trouble figuring that out by yourself, record what you eat for a week and ask a registered dietitian or a physician whether you are missing anything. If you are, the best course of action will probably be to improve your eating habits, not to take supplements.

As a rule, don't take more than the RDA amounts except on medical advice. And avoid doctors or nutrition consultants who recommend vitamins as a cure-all.

CU urges that several things be done to clean up the vitamin marketplace. The FDA should evaluate the claims made by promoters of vitamins and publicize its findings. It should also work with the pharmaceutical industry to develop voluntary standards for vitamin-product formulations. The Federal Trade Commission should attempt to stop misleading advertising related to vitamins. And the pharmaceutical profession should recognize the pushing of unnecessary supplements as an ethical issue that deserves its serious attention.