L-Arginine, readily available in the form of dietary supplements (100, 250, 500 mg capsules and tablets), is regulated by the provisions of the Dietary Supplements Health and Education Act (DSHEA) of 1994. A dietary supplement is “a product (other than tobacco) that is intended to supplement the diet that bears or contains one or more of the following dietary ingredients: a vitamin, a mineral, an herb or other botanical, an amino acid, a dietary substance for use by man to supplement the diet by increasing the total daily intake.”33 However, the DSHEA regulations are extremely lax and there are essentially no requirements for content uniformity, stability, dissolution characteristics or bioavailability. Consumers may incorrectly conclude that since the product is sold in a pharmacy and shelved in the general vicinity of over-the-counter drugs like acetaminophen or aspirin (regulated as drugs), the product was produced with the same rigorous manufacturing controls required of all drugs. While there are no reports indicating problems with L-arginine-containing dietary supplements, the number of products that undergo pharmaceutical and quality assurance testing is unknown. A product for L-arginine supplementation in the form of a medical food has recently been developed (HeartBar); it delivers L-arginine and a number of other antioxidants, vitamins and fiber. These other components have been shown to be of some benefit to patients with cardiovascular disease. A medical food is “formulated to be consumed or administered enterally under the supervision of a physician and is intended for the specific dietary management of a disease or condition for which distinctive nutritional requirements on the basis of recognized scientific principles are established by medical evaluation.”33 Sold as a medical food, this product is intended to be used under a physician’s supervision and generally would be expected to be of a higher pharmaceutical quality than dietary supplements. Healthcare providers should be aware of the effects of medical food use, whereas there may be a lack of knowledge associated with use of dietary supplements. |