Millions of people take supplements with the hope of living longer or having healthier life. It is estimated that about 150 million Americans take dietary supplements regularly.1
Pharmacists and other health-care professional receive a lot of inquiries about dietary supplements. It is obvious that consumers want to know more about the dietary supplements they are taking.
Dietary supplements by law are products taken by mouth that contain dietary ingredients to supplement the diet. The dietary ingredient may include vitamin, mineral, amino acid, a concentrate, metabolite, extract, enzyme, herb or other botanicals.2,3 This means that dietary supplements are more than vitamins and minerals. They come in a variety of forms such as tablets, capsules, powders, energy bars or drinks.
Any of the dietary supplements can be purchased without prescription. They are assumed to be safe unless proved otherwise. Unlike prescription medications, they are not required to go through clinical testing to establish their safety and efficacy. Therefore, dietary supplement manufacturers can market their product without any approval from the Food and Drug Administration (FDA), the federal agency that oversees the dietary supplement industry.
FDA has no power over which dietary supplement enters the market. However, the FDA has the power to have a supplement withdrawn from the market if it is determined to be dangerous and unsafe to use. Usually, the FDA starts the investigations into the safety of a dietary supplement after receiving side effects complaints from consumers and health professionals. That is why it is very important to report any unusual symptoms after taking a dietary supplement to the FDA at 1-800-FDA-1088 or www.fda.gov/medwatch/how.htm. FDA does not have the power to have a supplement withdrawn from the market if it does not do what it is promoted to do.
DIETARY SUPPLEMENTS are not expected to cure or treat diseases. Manufacturers of dietary supplements cannot make such claims. They can promote their product by claiming that it can help to reduce the incidence of a disease or related condition. For instance, a calcium supplement manufacturer can legally claim that calcium may reduce the risk of osteoporosis or calcium builds stronger bones. The manufacturer cannot claim that the calcium supplement can prevent or cure osteoporosis.
Many of the supplements are marketed without the need for extensive clinical trials required by prescription drugs. As a result, manufacturers of herbal supplements sometimes make claims based on their own presentation of studies without any FDA approval. This has created some concerns within the Federal Trade Commission (FTC). In 2003, the FTC sent more than 280 advisory letters to different retailers of dietary supplements warning that their Web site claims must be supported by scientific evidence.4 The absence of such scientific evidence makes it difficult for consumers to know what they are taking, or if the ingredients match what is on the label.
Here are some steps to take before choosing a dietary supplement:
* Talk to your pharmacist or doctor about any dietary supplements you are taking or considering taking since most of the ingredients in the products can interact with prescriptions or over-the-counter medications you may be taking.
* While some people may benefit from some supplements, there can also be a potential risk for using them. Many dietary supplements on the market contain substances that can be harmful or life threatening when taken with some prescription or over the counter medications. For example:
A combination of the prescription heart medication digoxin and a supplement containing calcium can lead to improper heartbeat and heart failure.5,6
A supplement that contain vitamin K when taken together with warfarin (Coumadin) the blood thinner medication can prevent the blood from being ‘thin’ and lead to clots.7 This can be dangerous and life threatening.
St. John’s Wort supplement can reduce the potency of a class of antidepressant medications called SSRI (e.g. Prozac, Paxil Celexa, Zoloft) when taken together. St. John’s Wort supplement can make about 50 percent of prescription medications ineffective and may need higher doses of the prescription medication to be effective.8
* Be cautious about label claims. Labels that sound too good to be true are usually the case. Example of false claim labels can be, "cure all," "can treat or cure a disease," "lose weight easily," "totally safe" and "no side effect."
* Look for the United States pharmacopoeia (USP) label. This label on the product indicates that the supplement product has been tested for purity, identity and potency and also the manufacturing process and package inserts have been voluntarily verified by USP, a nonprofit organization that sets standards for pharmaceuticals in the U.S.
* Do not jump onto headlines by the media to buy dietary supplements. Health advice is usually based on research over time and not just a single study that the media is excited about.
In the absence of required rigorous clinical trials by the FDA to establish the safety and efficacy before dietary supplement enters the market, the burden lies with the consumer to make informed decisions and choices on what dietary supplements to take and when to take them. While a lot of supplements are out there that may be exaggerated in their functions, good products are on the market that can help to promote good health outcomes. But until established quality and efficacy become a requirement before a supplement is put on the market, most of that work will have to be done by the consumer, preferably with the assistance of a medical doctor or a pharmacist. As a consumer, your best protection is curiosity and scrutiny.
A resident of Springfield, George O. Ofosu is pharmacy doctoral candidate at Virginia Commonwealth University and Consumer Health Information Corporation of McLean.