Attachment A: The Choices Doctors Face When Using Dietary Supplements.  How Products are Made.

Are there differences among the various products made of particular supplements such as vitamin C and vitamin A?

Yes. Supplements containing Vitamin C (whether alone or in combination) can come from different sources; corn, beet, and sago palm. In addition, Vitamin C may be buffered or esterized, and different manufacturing processes may result in the introduction of various flowing agents, lubricants and fillers.

About 20 different vitamin A products are offered for use in the nutritional industry. Almost all contain some stabilizing agents such as BHT, BHA, “edible vegetable oils,” sodium benzoate, sorbic acid, DI-alpha tocopherol, methylparaben, propylparaben and potassium sorbate. Many as well contain modified food starch, sugar, acacia, lactose, fractionated coconut oil or peanut oil.

Can these differences affect the patient?

Yes. There is the possibility of patient sensitivity to some of the sources and additives utilized in the manufacture of tablets and capsules. There is the additional factor that different patients have ranges of absorption and utilization. A physician may encounter patients returning “time release tablets” that didn’t produce the desired therapeutic effect. The company that produced the product may be high quality manufacturer and the tablets in question will disintegrate every time, at the correct dissolution rate according to USP (United States Pharmaceutical) procedure. Unfortunately, the GI tract of that particular patient does not fall into the standard.

  What would cause a sensitive patient to react?

  • Potentially allergenic ingredients may be present in the encapsulation of tableting process itself and therefore may or may not be labeled as part of the supplement ingredient. Examples are Sodium benzoate, BHT, BHA, Lactose, peanut oil, hydrogenated Cottonseed oil, sorbic acid, fractionated coconut oil, and cornstarch.
  • Polymer plastic solvents in tablets cause the time release action. A patient with chemical sensitivity may react to one solvent and not another, and again not or maybe only if bleach is present in the mix.
  • Tablets are glazed. The terms pharmaceutical glaze, resinous glaze, Pure Food Glaze all mean shellac, which may or may not have more Acetone per tablet than an equal amount of nail polish remover.
  • Capsules are made of pork skins or beef bone and skin, which is natural enough, but even hypoallergenic capsules may be coated with ZEIN. The label may not explain that ZEIN is actually water soluble protein of corn, and can still cause allergic reaction in corn sensitive patients.

Are there other concerns besides allergy sensitivity and bio-availability?

Persons requiring vegetarian or kosher products would be concerned about animal based capsules. More unknown, is that USP Oleic acid and glycerin, used in table coating, are loosely standardized formulas obtained by the hydrolysis of various animal and vegetable fats and oils.

Why is this an issue for supplements and not drugs?

Tablets used in nutritional field, by necessity are composed of high dosage active ingredients (such as Ascorbic Acid…1000mg.), not high potency, low dosage ingredients found in the pharmaceutical industry (such as Valium, 10mg). Larger tablets in most cases require the use of binders such as hydrogenated oils, while small tablets may be manufactured using simple cellulose derivatives.

Position: To assure quality of care in the therapeutic use of dietary supplements, patients must be able to freely access them through physicians who are educated and trained in their preparation and use.


  1.  U.S. Congress, Office of Technology, Assessment Unconventional Cancer Treatments, OTA-H-405 (Washington, DC: US Government Printing Office, September 1990)
  2. JAMA 193;269;3030 The Uncritical Acceptance of Technology
  3. (1846) Article 16, §31
  4. Texas Criminal Court of Appeals, Ex parte Halsted, 182 S.W.2d 479, 1944