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Hot Topics In Nutrition:  Supplements

Supplements take many forms, including multivitamins, individual vitamins and minerals, meal replacement drinks and bars, herbal preparations, and aids advertised to increase muscle (“bulk up”), decrease body fat (“fat burners”), or increase energy (“ergogenic aids”).

Important considerations apply to all of these. Unlike prescription medications, supplements are not highly regulated by the Food and Drug Administration (FDA). This means that health claims can be made that are not backed by evidence, and contents may not necessarily correspond with labels. For example, the potentially active ingredient in a product may not be present in the amount indicated, if an amount is indicated at all. Even more worrisome, other additives or contaminants may be present that are not listed on the label, some of which may be either toxic or banned substances.

The supplement industry in the US is a multibillion dollar one. Populations that are highly targeted by supplement industry advertising include athletes, young adults, people interested in weight loss, and the elderly.

Unfortunately, it is not clear which supplements are effective and without risk. Innumerable products are available, with more appearing all the time. So, it is important to be skeptical about supplements that promise magical results. Claims about fat burning, weight loss, muscle building, and energy promoting are often the most suspect. 

Magic is not the most reliable substitute for a healthy lifestyle that incorporates good nutrition, a reasonable amount of rest, and a healthy exercise/ training pattern. A balanced food intake usually includes all the vitamins and minerals needed to maintain health.

Inadequate nutrient intake or a specific nutrient deficiency (such as iron deficiency) would be reasons to consider a multivitamin or mineral supplement. It is best to consult with a health professional when considering supplements other than multivitamins produced by a reliable manufacturer.

Consider these questions

You may find that asking these questions about a supplement will inform your decision about whether or not to use it. 

1. Is the information I’m getting from a reliable source? Are there any long-term studies? (Note that advertising and information from the web are not always reliable sources.) Do the claims sound too good to be true?
2. What about short-term or long-term risks—are there any long-term studies?
3. What is the cost?
4. Do the benefits outweigh the costs and risks, or are there too many unknowns?
5. Is the manufacturer reliable? Is the item certified by US Pharmaceuticals (USP)?
6. Why do I think I need this supplement, and would it be better to consult with a medical professional?

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Example

An example of a supplement that can potentially cause problems is St. John's Wort, an herbal preparation popularly used to self-treat depression. 

Potential advantages include:

1. It may be lower in cost than antidepressant medications.
2. It may seem more natural and self-empowering to use an herbal product.

Disadvantages include: 

1. The active ingredient(s) are present in variable and unmeasured dosages depending on preparation.
2. St. John's Wort can make some forms of depression worse.
3. It is known to interact with other medications and make them less effective (for example, birth control pills).
4. Its use may discourage more effective modes of treatment.

For more information

More information about supplements is provided by the FDA (e.g., "Tips for the Saavy Supplement User: Making Informed Decisions and Evaluating Information" )and the New York Online Access to Health (NOAH) Nutrition.