Market Importance of Herbal Products
The use of herbal medicines in the USA is less widespread than in the majority of developed nations. The reason is that their distribution has mostly been limited to health food stores which are frequented by only a small proportion of the population. Wider distribution through pharmacies is difficult because no medical claims may be made and consumers are dependent on advice from pharmacists who, in a majority of cases, have little knowledge about medicinal herbs .
In the late 1930s, the Food, Drug and Cosmetic Act was passed and, from that time on, the Food and Drug Administration (FDA) has regulated as drugs any products which claim to treat, cure, mitigate or prevent a disease. Thus, for any herbal medicine claims to be allowed, the same procedures must be followed as for a chemical drug. Most natural products in the United States are regulated as foods or food additives even though many are used by consumers as folk medicines. As such, most of the regulatory action occurs in the area of safety. Where a herb is "generally recognized as safe" (GRAS), this means ensuring that no claims are made and products are not being misbranded or adulterated. Natural products theoretically have GRAS status, so long as qualified experts confirm this and are not contradicted by other experts. According to a court case in 1983, the requirement of "common use in food" was not restricted to use in the USA, but applied also to herbs without a history of use in the USA .
Some better known medicinal herbs are listed by the FDA for over-the-counter status. However, an 18-year review of over-the-counter drugs has resulted in most of those medicinal herbs being dropped, mainly because the US herbal industry failed to submit evidence to support their use as such. In November 1992, the FDA established a new advisory committee of outside experts for over-the-counter drugs .
Since 1976, following the "Proxmire Bill", a civil regulation for the Health Food Market states that foods, including dietary supplements and herbs, are not drugs. This law kept the FDA from making monographs on dietary supplements, vitamins, minerals and herbs, as has been done for several kinds of drugs .
In 1990, Congress passed the Nutrition Labelling and Education Act (NLEA) which required that all food products must have nutritional labelling, and that the FDA has to establish criteria for approving health benefit labelling for foods. An exemption to the NLEA was introduced noting that vitamins, minerals, herbs and similar nutritional substances are consumed differently from conventional food and thus should be subject to more lenient standards of evidence for their health benefits. Congress gave the FDA one year to receive public comment as to how to establish standards and procedures for the assessment of health claims for the supplements that where exempted from the rest of the NLEA. A proposal submitted by the American Herbal Product Association was rejected by the FDA .
Dietary Supplements, not Food Additives
In October 1994, the Dietary Supplement Health and Education Act  recognized that dietary supplements have been shown to be useful in preventing chronic diseases and therefore help limit long-term health care costs. Herbs and other botanicals, vitamins and minerals now fall under the definition of a dietary supplement which is presented in a dosage form such as capsules, tablets, liquids etc., and which is not represented as a conventional food, but which is labelled as a dietary supplement. Dietary supplements do not include substances first sold as drugs and later as dietary supplements, nor do they include substances undergoing clinical studies which were not first sold as dietary supplements. The law provides that a dietary supplement is considered to be a food which does not need pre-market approval by the Food and Drug Administration (FDA), and not as a food additive which needs a pre-market approval by the authority. A statement on the label of a dietary supplement is allowed if a benefit is claimed related to a classical nutrient deficiency, if the role of the nutrient or dietary ingredient is described, or if the documented mechanism of action to maintain a function is characterized. In addition, however, it must be clearly stated that this statement has not been evaluated by the FDA, and that this product is not intended to diagnose, treat, cure or prevent any disease. Furthermore, the ingredients, and the plants or parts of plants respectively, and their quantity must be clearly listed. If the supplement claims to conform to an official compendia standard (USP) for which there is an official specification, and fails to meet that standard, the product is regarded as misbranded. This also applies in the case of a product which is not covered by an official compendium, but which fails to have the identity, strength, quality, purity which it may claim to have.
The new law provides for the establishment of an Office of Dietary Supplements within the National Institutes of Health, which should explore the role of dietary supplements to improve health, and should promote scientific studies of the benefits of the dietary supplements .
The signing into law of the Dietary Supplement Health and Education Act in October 1994 may accelerate the recognition and increase the importance of herbal products in the US market, because the law may give an opportunity to market these products as dietary supplements, providing there are data to show that the products are safe and to support any claims with reasonable substantiation. The chances, however, to market a herbal product as a drug and to give it medicinal claims are low, because at present the FDA does not accept bibliographic evidence of effectiveness, but prefers randomized controlled trials as evidence of efficacy .