Abstract and Introduction
The goal of this review is to evaluate the efficacy of commonly available dietary supplements in the treatment of hypertension, using the average blood pressure reduction achieved with the implementation of lifestyle modifications as a standard. For this reason, the authors focus on the antihypertensive potential of these agents rather than pharmacology, pharmacokinetics, adverse effects, or supplement-drug interactions. For the purpose of this review, dietary supplements are defined as exhibiting some evidence of benefit if a systolic blood pressure reduction of 9.0 mm Hg or greater and/or a diastolic blood pressure reduction of 5.0 mm Hg or greater has been observed in previously published, peer-reviewed trials. These defining limits are based on the average blood pressure reduction associated with the implementation of certain lifestyle modifications. Agents with some evidence of benefit include coenzyme Q10, fish oil, garlic, vitamin C, and L-arginine.
Dietary supplements have become the focus of debate among suppliers, the health care community, government regulatory agencies, and the general public. While being used for centuries to treat a wide variety of health conditions, contemporary concerns primarily surround the issues of safety and efficacy. In 1994, the US Food and Drug Administration defined "dietary supplement" in the Dietary Supplement Health and Education Act as "a product taken by mouth that contains a 'dietary ingredient' intended to supplement the diet." Dietary ingredients may include vitamins, minerals, herbs or other botanicals, amino acids, and substances such as enzymes, organ tissues, glandulars, and metabolites. Supplements may also be extracts or concentrates of those substances. Because dietary supplements are easily accessible and because of the frequent misinterpretation that all natural products are also safe, patients may choose these agents for blood pressure control. Self-treatment with dietary supplements without the supervision of a health care provider may be very dangerous. For example, patients often utilize garlic in the treatment of hypertension, and garlic is known to interact with numerous medications. Garlic may enhance the anticoagulant effects of warfarin and the hypoglycemic effects of oral diabetic agents. Concomitant use with garlic can also result in decreased serum levels of several drugs used in the treatment of human immunodeficiency virus. Health care providers must be familiar with the available supplements used, for example, to "support a healthy cardiovascular system" and address the appropriate use of supplements with patients along with issues like medication interactions. Information of questionable reliability is readily available to the public and providers must be prepared to authoritatively answer questions concerning these agents.
In a recent analysis tracking the amount and quality of information available on the Internet, out of 2600 Web sites identified by using the search terms "high blood pressure" and "treatment," 58% focused on alternative therapies and only 36% discussed conventional antihypertensive drugs. In the same study, it was noted that 12 of the 14 herbs listed on the Internet as effective remedies for high blood pressure have actually been shown to raise blood pressure in valid scientific studies. A survey conducted in Alabama in 2000 revealed that 46% of the population was taking nutritional supplements and 26% were taking herbal supplements. As self-treatment with dietary supplements continues to increase in popularity, health care providers must be responsible for educating patients about the efficacy, or lack of efficacy, of these agents.
The goal of this review is to evaluate the efficacy of dietary supplements in the treatment of hypertension, using as a benchmark the average blood pressure reduction noted with the incorporation of lifestyle modifications. For this reason, only the antihypertensive potential of these agents, rather than pharmacology, pharmacokinetics, adverse effects, or drug interactions, is discussed.
© 2004 Le Jacq Communications, Inc.
Cite this: The Natural Treatment of Hypertension - Medscape - May 01, 2004.