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Are Vitamins Really Good For You?

As far back as the mid-1700s a Scottish surgeon proposed that lemons and limes could prevent and cure scurvy, a potentially fatal disease common to sailors and others without access to fresh foods. But it wasn’t until the early 1900s that scientists figured out the fruits contained a chemical we now call vitamin C.

Today, we know a lot more about vitamins and they way they influence our health. But, misinformation still abounds. This article will help you decide whether you need vitamin supplements and how to get the most inexpensive, effective dosages.

You Need Your Vitamins
Vitamins are micronutrients – substances your body needs in very small amounts for growth, digestion and the healthy function of nerves.

In most cases the body can’t make its own micronutrients. Ideally, they’re supplied by a well-balanced diet. Fruits, vegetables, whole grains and fresh meats are good sources of a wide range of vitamins and other essentials.

Although severe vitamin-deficiency diseases such as scurvy, beriberi (caused by a lack of vitamin B1), and rickets (the result of inadequate vitamin D) have been all but eliminated in developed countries, more subtle deficiencies are not uncommon even in North America.

According to a scientific review published in the Journal of the American Medical Association (JAMA) in June 2002, less than optimum vitamin intakes, “even well above those causing deficiency syndromes, are risk factors for chronic diseases such as cardiovascular disease, cancer and osteoporosis.”

Vitamin deficiency can also reduce resistance to infections and increase the risk of birth defects.

The article goes on to say that “A large proportion of the general population is apparently at increased risk for this reason.” The authors conclude that it seems “prudent” for all adults to take a vitamin supplement.

That doesn’t mean vitamins can prevent all diseases or that more than the recommended dietary allowance (RDA) is better. Indeed, the RDAs of vitamins meet the needs of an estimated 97 percent to 98 percent of healthy individuals, says the National Academy of Sciences.

Who Should Take Vitamins?
Whether you should take vitamin supplements depends mostly on how well-balanced your diet is. You’re more likely to need a vitamin supplement if you:

  • Don’t eat five servings of fruits and vegetables daily

  • Are a vegetarian

  • Are on a low-calorie diet or tend to skip meals

  • Have a limited diet as a result of food allergies

  • Have a digestive disorder

  • Smoke

  • Drink alcohol to excess

  • Are pregnant

Don’t confuse vitamins with other forms of dietary supplements. The supplement category includes vitamins as well as minerals, herbal and botanical preparations, enzymes and other ingredients. Although the body has daily requirements for vitamins and minerals, no need for the other kinds of supplements has been established.

If you’re unsure about the contents of a product, check the package. All supplements must include a Supplement Facts Label indicating how much of the daily requirement the product contains. If you see an asterisk (*) instead of a number in the Daily Value column, it means no daily value has been established.

If your eating habits could be better, a daily multivitamin that offers no more than 100 percent of daily requirements does no harm and may do you good. If you have a chronic illness or take prescription medicines, discuss it with your doctor first.

For most people a single multivitamin tablet fills the bill. The authors of the 2002 JAMA article recommend multivitamins rather than a handful of specific vitamin pills because “multivitamins are simpler to take and cheaper than the individual vitamins taken separately.”

Bottom line: Think of vitamins as an inexpensive insurance policy and a complement to, not a substitute for, a healthy diet.

Take The Right Vitamins For Your Age
Children need vitamins formulated specifically for them because their RDAs are lower than those for adults, and overdoses can be harmful.

After age 18, young people can take adult multivitamins.

Healthy men and women under 50 have similar daily requirements for most vitamins, but there are some special cases.

Pregnant women should ask their physician about prenatal vitamins, and women of childbearing age may benefit from supplemental folate (vitamin B9) to help prevent birth defects of the brain and spinal cord.

Adults over age 50 have a few specific needs. The RDA for vitamin B6 (found primarily in fortified cereals) increases about 30 percent for men and 15 percent for women. The requirement for vitamin D, needed especially for bone health, doubles in both sexes. And because some older people are less able to absorb vitamin B12 from food, some experts recommend they take a supplement.

Those who need higher doses of specific vitamins should buy them as individual supplements rather than double up on multivitamins, doctors advise.

Be Cautious When Taking Vitamins
The primary caveat with multivitamins is that more than the RDA is not better – and can be harmful.

Too much vitamin A can reduce bone density and cause liver problems. In pregnant women, it can cause birth defects. Excessive vitamin D can also be toxic and cause calcium deposits. Overdoses of vitamin B6 may cause damage to nerves in the arms and legs.

Megadoses of vitamin E pose dangers, too. An analysis of 19 studies, reported in the Annals of Internal Medicine in 2004, indicates that people who take more than 400 IU of vitamin E daily for at least a year had a higher death rate from all causes.

In a few cases vitamins don’t combine well with drugs. For instance, vitamins E and K both have blood thinning effects, so taking them along with a prescription drug such as Coumadin – or even aspirin or herbal supplements such as ginkgo biloba – could make internal bleeding more likely.

Also be aware that taking a multivitamin doesn’t exempt you from eating your veggies and whole grains. These food groups also contain fiber and biologically valuable compounds that build health and help prevent disease. Scientists are continually learning more about these food components, and it’s unlikely all will ever be available from pills alone.

If you’re healthy, there’s probably no need to make a special appointment with your physician before taking vitamins. The next time you visit your doctor, discuss the fact that you’re taking a multivitamin or thinking about it.

But if you have questions about supplementation or have health problems, talk things over with your doctor. The FDA’s Center for Food Safety and Applied Nutrition advises, “If you are pregnant, nursing a baby, or have a chronic medical condition such as diabetes, hypertension or heart disease, be sure to consult your doctor or pharmacist before purchasing or taking any supplement.”

Finally, if you’re a candidate for surgery, you may need to discontinue some supplements several weeks beforehand. Inform your doctor about everything you’re taking.

Weigh The Cost Of Vitamins
Vitamins are inexpensive to produce, yet manufacturers offer hundreds of options whose annual cost ranges from less than $10 (basic formulas) to $600 or more. In 2003 alone the U.S. supplement industry as a whole pulled in an estimated $18.8 billion in sales, according to a report published in Nutrition Business Journal.

Companies charge more for vitamins in liquid, chewable and time-release formulas as well as those with added herbs, botanical ingredients or antioxidants and those touted as “all-natural.”

Of course, big-name brands with heavy marketing and advertising expenses cost more than house brands.

For example, you could spend more than $650 a year on Dr. Weil’s Select Formulas Memory Support, which includes a mix of multivitamins, antioxidants and herbs.

But there’s no need to get fancy. You can buy a year’s supply of Rite Aid One Daily multivitamins for about $6, Walgreen’s Gold Seal for around $8, and One-A-Day Essential for approximately $26.

Does brand matter? Not really. The JAMA report notes that “the contents of basic multivitamins are remarkably similar across brands.”

In addition, in June 2007 the FDA announced a ruling that established stronger good-manufacturing-practice requirements for the makers of all dietary supplements, including vitamins. In a 2007 news release the FDA states that the rule “ensures that dietary supplements are produced in a quality manner, do not contain contaminants or impurities, and are accurately labeled.”

For More Information
To learn more, visit these government-sponsored and independent Web sites.

The National Institutes of Health Office of Dietary Supplements
News, nutrient recommendations and a searchable database of supplements
http://dietary-supplements.info.nih.gov/

Consumerlab.com
An independent site with news on supplements, and prescription and over-the-counter medications
http://consumerlab.com

Vitamins A to K
A patient page prepared by the Journal of the American Medical Association and published in June 2002
http://jama.ama-assn.org/cgi/reprint/287/23/3166.pdf