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Resource Description: 
Learn more about nutritional supplements from the doctor who coined the term.
The U.S. Food and Drug Administration's Center for Food Safety and Applied Nutrition offers tips for making informed decisions about food supplements.
Information about complementary and alternative medicine from the National Institute of Health.
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Nutritional Supplements, often referred to as "nutraceuticals", are not magic pills. They are food substances that can provide medical or health benefits, including the prevention and treatment of disease. Considered a non-traditional, alternative medicine, they can also pose risks. In this episode of Second Opinion, you will learn about the importance of communicating with your doctor to determine whether traditional medicine, alternative medicine, or a combination of the two is the best approach for you.

"Nutraceutical" is a term that was coined in the late 1980's by Stephen DeFelice, M.D., founder and chairman of the Foundation for Innovation in Medicine. He defined nutraceutical as "any substance that is a food or a part of a food and provides medical or health benefits, including the prevention and treatment of disease."

While the term has since taken on a range of different meanings, DeFelice was very specific in outlining the types of products that fall under the nutraceutical umbrella. They include:

  • Dietary supplements
  • Isolated nutrients
  • Specific diets
  • Genetically engineered designer foods
  • Herbal products
  • Functional foods such as cereals, soups, and beverages

While nutritional supplements are highly controversial within the traditional medical community, they are in high demand by consumers in the U.S. and other parts of the world. One account puts 2003 sales of nutraceuticals in the U.S. at $31 billion. And that figure is expected to grow substantially over the next several years.

Nutritional supplements can hold great healing potential, as evidenced by products such as Benecol, which helps to reduce cholesterol. But they may also hold the potential for doing harm, which was the case with ephedrine, a widely used botanical ingredient in weight-loss products. The substance was banned by the U.S. Food and Drug Administration after it was linked to significant adverse health effects, including heart attack and stroke.

Even after highly publicized events like the ephedrine ban, vast numbers of consumers continue to buy nutritional supplements - often without having solid information about their safety and effectiveness, possible side effects, interactions with prescription medicines, or the impact they may have on existing medical conditions.

While there is growing acceptance of nutritional supplements by some mainstream physicians, many members of the medical and scientific communities remain concerned that many products entering the market lack adequate efficacy and safety data. Professionals on both sides of the fence agree that there is an urgent need for funding to support high-quality scientific research, testing, and clinical trials before nutritional supplement products are introduced to consumers.


Quick Facts

More than 100 million Americans take dietary supplements daily.

No one disputes the health benefits of diets rich in fruits, vegetables, and whole grains. Scientists are working to identify the exact components in these diets that confer protection against chronic diseases such as heart disease and cancer.

Currently, universities, industry, non-government organizations, and government are collaborating on clinical trials to demonstrate the effectiveness of functional foods.
Many vitamins and minerals are not absorbed well and, as a result, are not retained by the body. 

Some appetite suppressants can create psychological dependence because they contain phentermine, which is chemically similar to amphetamines. Others can cause insomnia, drowsiness, irritability, or depression.

Synthetic vitamins are usually the same as natural vitamins, but natural vitamins usually cost more.

Like prescription medicines, supplements should be kept out of reach of children in a dry, cool place. Avoid hot, humid storage locations, such as the bathroom.

Vitamin E and beta-carotene supplements do not have preventive effects on stroke in middle-aged men who smoke, Finnish and US researchers report. The findings come from further analysis of data from the Alpha Tocopherol, Beta Carotene Cancer Prevention Study, a trial involving more than 29,000 male smokers between 50 and 69 years. It was originally intended to see if these antioxidants cut the risk of lung cancer.
Despite some reports that antioxidant vitamins have cardiovascular benefits, a panel of experts at the American Heart Association (AHA) has concluded that there is too little evidence to recommend taking antioxidant supplements to reduce the risk of heart disease. Instead, the AHA panel advises you to get plenty of antioxidants from food sources such as fruits, vegetables, whole grains, and nuts.

Some people take amino acid (the building blocks of protein) powders to increase muscle. Research shows that eating more protein or more amino acids does not lead to increased muscle building. Exercise determines muscle building.

According to the 2002 edition of the National Center for Health Statistic's National Health Interview Survey, Americans are most likely to use Complementary and Alternative Medicine (CAM) for back, neck, head, or joint aches, or other painful conditions; colds; anxiety or depression; gastrointestinal disorders; or sleeping problems. CAM is most often used to treat and/or prevent musculoskeletal conditions or other conditions involving chronic or recurring pain.

Ask Your Doctor

Mark Hyman, MD
Co-Medical Director, Canyon Ranch
Author, "Ultraprevention, The Six Week Plan that Will Make You Healthy for Life" and "The Detox Box, A Program for Greater Health and Vitality"
Editor-In-Chief, "Alternative Therapies in Health and Medicine"

This list of questions is a good starting point for discussion with your doctor; however, it is not a comprehensive list.

  1. Do the majority of Americans suffer from vitamin deficiencies?
  2. Do you think vitamins just make expensive urine? 
  3. Do vitamins play a role in disease prevention?
  4. What vitamins should I be taking to prevent heart disease, cancer, Alzheimer's, etc?
  5. Are there supplements I should take to prevent and/or treat osteoporosis?
  6. Are all calcium supplements the same? If not, what is the best type?
  7. Is it dangerous to take doses higher than the RDA (recommended daily allowance) or DRI (dietary reference intakes)?
  8. I have heard a multiple vitamin can reduce inflammation.  Is that true?
  9. Are all vitamins the same?  If not how do I choose the best quality?
  10. Do you check for folate deficiency with a homocysteine blood test?
  11. Which supplements are harmful to me or will interfere with other medications or treatments I am on?
  12. Which supplements have not been shown to be beneficial?

Key Point 1

To ensure that your needs are met, you must take an active role in your own health care.

Communication With Your Doctor

Many people come from a generation that did not ask questions of doctors. They expect doctors to figure out their problems and then provide the answers. Others want to ask questions, but do not when the doctor seems rushed. However, good communication requires a partnership. To provide the best possible care, your doctor needs you to provide details about your illness and about other care you are receiving, including medications and supplements.

Product Research

The intent of marketing is to sell services and products. Information often is slanted to accentuate the benefits and downplay side effects, risks, and dangers. Before purchasing and using a nutritional supplement, consider the following points:

  • Ask yourself whether the claims sound too good to be true.
    Do the claims for the product seem exaggerated or unrealistic? Does the product have testimonials but no evidence from clinical trials? Are simplistic conclusions being drawn from a complex study? Learn to distinguish hype from evidence-based science. Question so-called experts on their training and knowledge in nutrition or medicine.
  • Think twice about chasing the latest headline.
    News stories are often too brief to include important details. Sound healthcare is generally based on a body of research, not a single study. Be wary of a quick fix that departs from previous research and scientific beliefs. Science does not proceed by dramatic breakthroughs, but by taking many small steps, slowly building toward a consensus.
  • Check your assumptions.
    • "Even if a product may not help me, it at least won't hurt me."
      When consumed in large enough amounts, for a long enough time, or in combination with certain other substances, all chemicals can be toxic - even those derived from natural sources
    • "When I see the term 'natural,' it means that a product is healthful and safe."
      The term natural on labels is not well defined. There is no guarantee that these food-like substances have milder effects or are safer to use than prescription drugs. Their ingredients may interact with drugs or may be dangerous for people with certain medical conditions.
    • "A product is safe when there is no cautionary information on the product label."
      Dietary supplement manufacturers are not required to include warnings about potential adverse effects on the labels of their products.
    • "A product recall guarantees that all such harmful products will be immediately and completely removed from the marketplace."
      A product recall of a dietary supplement is voluntary and does not necessarily remove all harmful products from the marketplace.
  • Contact the manufacturer for more information.
    If you cannot tell whether the product you are purchasing meets the same standards as those used in the research studies you read about, check with the manufacturer or distributor. The product label includes contact information. Your questions might include:
    • What evidence-based research do you have to substantiate the claims you have made for the product? What tests have you conducted to ensure the safety or efficacy of the ingredients?
    • Do you have a quality control system in place to ensure that the product contains only those ingredients listed on the label and is free of contaminants?
    • Have you received any reports of adverse effects from consumers who have used the product?

While the Internet is a rich source of good health information, it is also a forum for spreading myths, hoaxes, and rumors. Be skeptical of overly emphatic language. Ask your doctor to recommend respected organizations, search those sites, and discuss your findings with your doctor. Ask yourself the following questions:

  • Who operates the site?
    Is the site run by the government, a university, or a reputable medical or health-related association? Is the information written or reviewed by qualified health professionals, experts in the field, academia, government, or the medical community?
  • What is the purpose of the site?
    Is the purpose of the site to educate the public or just to sell a product? Most nonprofit and government sites contain no advertising and offer free access. Be wary of practitioners or organizations whose main interest is in marketing products, either directly or through sites with which they are linked. Commercial sites should clearly distinguish scientific information from advertisements.
  • What is the source of the information and does it have any references?
    In the case of a scientific study, has it been reviewed by recognized scientific experts and published in reputable peer-reviewed journals like the New England Journal of Medicine? Does the information say "some studies show " or does it state where the study is listed so that you can check the authenticity of the references? For example, can the study be found in the National Library of Medicine's database of literature citations?
  • Is the information current?
    Check the date when the material was posted or updated. Dated material may not contain the most recent research or other findings such as side effects or interactions with other products. Health and medical sites should be updated frequently.

Key Point 2

The FDA does not regulate dietary supplements.


In 1994, the Dietary Supplement Health and Education Act  became law, amending the Federal Food, Drug, and Cosmetic Act. DSHEA created a new regulatory framework for the safety and labeling of dietary supplements.

FDA's Center for Food Safety and Applied Nutrition (CFSAN) is responsible for the agency's oversight of dietary supplements. The Federal Trade Commission (FTC) regulates advertising, including infomercials for supplements and most other products sold to consumers. The U.S. Postal Inspection Service has laws that regulate the advertising and promotional material you receive in the mail.

Under DSHEA:

  • Dietary supplements are classified as foods and are assumed to be safe. They are subjected to limited regulatory oversight.
  • Manufacturers do not need to register with the FDA or get FDA approval before producing or selling dietary supplements.
  • Manufacturers are responsible for ensuring that dietary supplements are safe before they are marketed. A new dietary ingredient requires a pre-market review for safety. Otherwise, no law or regulation requires a firm to disclose information about the safety or benefits of its products.
  • The manufacturer is not required to include warnings, precautions, or side effects on product labels.
  • The FDA must prove that a dietary supplement is unsafe before it can take action to restrict the product's use or remove it from the marketplace. 
  • Manufacturers are not required to record, investigate, or forward to the FDA any reports of injuries or illnesses that may be related to the use of its products.

Because the FDA has limited resources for analyzing the composition of food products, it focuses first on public health emergencies and products that may have caused injury or illness. Enforcement priorities then go to products thought to be unsafe, fraudulent, or in violation of the law.
In 2004, American Medical Association (AMA) Trustee Ronald M. Davis, MD, told Congress, "Because existing law treats dietary supplements as foods, many consumers think they are safe. Many consumers believe these products have been approved by the government, when in fact they have not. Ephedra, for example, was on store shelves long after the risks of heart attack, stroke, seizure, and death were well documented. It took the FDA seven years to ban ephedra because DSHEA makes it difficult for the FDA to prove that a dietary supplement is unsafe. Yet, other dietary supplements such as bitter orange contain ephedra-like substances and are still available to consumers."


FDA regulations require dietary supplement labels to include the following information:

  • Descriptive name of the product, stating that it is a supplement
  • Name and place of business of the manufacturer, packer, or distributor
  • Supplement Facts panel, which identifies each dietary ingredient contained in the product
  • Ingredients list beneath the Supplement Facts panel, which includes all other ingredients

Manufacturers may make the following claims for their products:

  • Amount of a nutrient or dietary substance in a product
  • Intended benefits of using the product
  • Links between a food substance and disease or a health-related condition

Nutritional supplements cannot claim to treat specific conditions. A supplement promoted on its labeling as a prevention, treatment, or cure for a specific condition would be considered an unapproved - and thus illegal - drug.

Different requirements generally apply to each type of claim, as described in more detail on the FDA web site

For example, with certain claims, DSHEA requires the label disclaimer: "This statement has not been evaluated by the FDA. This product is not intended to diagnose, treat, cure, or prevent any disease."


Key Point 3

Anything you put into your body has an effect.

Supplement Choices

Many people do not receive all of the nutrients they need from their diets. Some groups, like pregnant women and older adults, have special nutritional needs and may benefit from dietary supplements. Though supplements do not replace the nutrients and benefits of eating whole foods, they can complement the diet.

Vitamins and minerals are substances your body needs in small but steady amounts for normal growth, function, and health. Your body cannot make these nutrients, so you must get them from the foods you eat or from supplements.

For recommendations about nutrients needed in the diet

In general, choose a multivitamin-mineral supplement that provides about 100% daily value (DV) of all the vitamins and minerals, instead of one that supplies, for example, 500 % DV of one vitamin and only 20% DV of another. The exception is calcium. You may notice that calcium-containing supplements do not provide 100% DV. If they did, the tablets would be too large to swallow.

If you are already taking individual vitamins or mineral supplements and have not told your doctor, discuss it at your next checkup. Before taking anything other than a standard multivitamin-mineral supplement of 100 % DV or less, check with your doctor, pharmacist, or registered dietitian.

Supplements can lose potency over time, especially in hot and humid climates. If a supplement does not have an expiration date, do not buy it. If your supplements have expired, discard them.

Supplement Risks

Many supplements contain active ingredients with strong biological effects. If you have certain health conditions and take these products, you may be placing yourself at risk. These products have the greatest effect on children, women who are pregnant or nursing, or those who have chronic medical conditions such as diabetes, hypertension, or heart disease.

  • Consumers cannot be sure that the product label matches the actual contents of the product.  Studies have shown a wide variation in the content of active ingredients in dietary supplements. For example, in an analysis of 24 ginseng products, one-third had no active ingredient. Worse, there have been reported cases of herbal products testing positive for arsenic, lead, mercury, and pesticides. 
  • Some supplements can be toxic.  High doses of some vitamins or minerals may cause health problems. For example, high doses of vitamin B-3 (niacin) can create or worsen liver problems. Over time, too much vitamin A may cause liver problems or weaken bones in women.
  • Some supplements may interact with prescription and over-the-counter (OTC) medicines. Taking a combination of supplements and medications (whether prescription or OTC drugs) could produce adverse effects, some of which could be life threatening. Be alert to advisories about these products, whether taken alone or in combination. For example: Coumadin (a prescription medicine), ginkgo biloba (an herbal supplement), aspirin (an OTC drug), and vitamin E (a vitamin supplement) can each thin the blood, and taking any of these products at the same time can increase the potential for internal bleeding. Combining St. John's Wort with certain HIV drugs significantly reduces their effectiveness. St. John's Wort may also reduce the effectiveness of prescription drugs for heart disease, depression, seizures, certain cancers, or oral contraceptives.
  • Some supplements can have unwanted effects during surgery. It is especially important before elective surgery to fully inform your doctor about any supplements you are taking. Supplement/drug interactions can cause changes in heart rate and blood pressure and increased bleeding, which could adversely affect the outcome of your surgery. You may be asked to stop taking these products at least 2 to 3 weeks prior to the procedure.

Medline Plus

Medline Description: 

Conduct an off-site search for Nutritional Supplements information from MedlinePlus.  These up-to-date search results are based on search terms specific to Second OpinionKey Points.

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