Therefore, exploitative dietary supplement makers — often com­pounding pharmacists not regulated by the Food and Drug Administra­tion (FDA) — have introduced and heavily marketed so-called bioidenti­cal, “natural” hormone preparations that contain plant-based estrogens derived from soy or yams. These sup­plement makers attempt to fool the public into thinking these hormones are better and safer than prescription estrogens.

None of these supplements have been approved by the FDA, and according to the widely respected journal Medical Letter on Drugs and Therapeutics, these products are “chemically modified to be structur­ally identical to endogenous [natural­ly occurring] hormones. Most FDA-approved single-entity hormones are also [natural] derivatives of soy or plants extracts and are structurally identical to hormones produced by the ovary.”

The May 31, 2010, issue of Medi­cal Letter contained a table (Table 1) describing the content and origin of several of these popular products:

According to the Medical Letter, “The FDA has reported sub-potency, super-potency and contamination of pharmacy-compounded drugs. In one 2006 survey, their potency ranged from 67.5 percent to 268.4 percent of the amount specified on the label­ing, and both sub- and super-potent active ingredients were found within the same sample.”

It goes on to say that:

Bioidentical products that contain progesterone, testosterone and estrogen can be expected to have the same adverse effects that con­ventional preparations have. Most bioidentical hormone preparations contain estriol … No drug product containing estriol has been ap­proved by the FDA and the safety and effectiveness of supplemental estriol is unclear. Endometrial cancer associated with bioidenti­cal hormone therapy has been reported.

The appropriately strong conclu­sion of this matter is that “there is no acceptable evidence that ‘bioidenti­cal’ hormones are safe or effective. Patients should be discouraged from taking them.” We strongly agree.

What You Can Do

Aside from avoiding bioidentical hormones for reasons stated above, even FDA-approved prescription estrogens should be used at the lowest effective dose and for the shortest duration consistent with treatment goals. This is because these products increase the risk of breast cancer, car­diovascular disease and dementia.

There is no question that an epidemic of breast cancer in women, now abating somewhat, was caused by several decades of massive use of estrogen-containing products (that has now decreased significantly).

Table 1. Some Preparations of Bioidentical Hormones