Vitamins, minerals, amino acids, some steroids, the pineal hormone melatonin, and herbal supplements all fall under the heading of nutritional products. The Food and Drug Administration classifies dietary supplements as foods, and not as drugs, so they are regulated differently than prescription drugs.

The FDA requires the manufacturer ensure the safety of their product before it goes to market. The Food and Drug Administration will only take action against any unsafe nutritional supplements after it reaches the marketplace.

Nutritional supplements are any product that is intended to supplement the diet and contain any of the following dietary ingredients:

A vitamin

A mineral

An herb or other botanical (excluding tobacco)

An amino acid

A dietary substance for use by people to supplement the diet by increasing the total dietary intake, or

A concentrate, metabolite, constituent, extract, or combination of any of the above

Furthermore, it must also conform to the following criteria:

It is intended for ingestion in pill, capsule, tablet, powder or liquid form.

It is not to be represented for use as a conventional food or as the sole item of a meal or diet.

It is labeled as a dietary supplement.

While hormones are not included in the above list, some hormones are labeled as "dietary supplements".

Keep in mind the possibility of interactions between a prescription drug and nutritional products. Just because a product is derived from "natural" or "herbal" sources does not assure its safety. Many herbal products produce pharmacological side effects. Just because herbal products are available without a prescription, medical advice is necessary because of the adverse effects of these products and the potential for drug interactions.

Dietary supplements are permitted to make structure and/or functional nutritional value claims. These are broad claims that the product can support the structure or function of the body, as in "glucosamine helps support healthy joints", "the hormone melatonin helps establish normal sleep patterns". The FDA must be notified of these claims within 30 days of their first use, and there is a requirement that these claims be substantiated.

When considering nutritional products, first evaluate whether or not you are getting enough of the vitamin, mineral or herbal supplement through your daily dietary consumption. Getting recommended daily allowances through a healthy, nutritious diet if favored over supplementation if that is a likely option.

However, if you recognize you are not getting what you need through diet alone, it is a good idea to ask your doctor or nutritionist what supplements and dosages he recommends. Always investigate before you begin taking any nutritional supplements to make sure the latest studies demonstrate the safety and effectiveness of its use.