The Medical Letter recently evaluated “bioidentical” hormones and concluded
There is no acceptable evidence that “bioidentical” hormones are safe or effective. Patients should be discouraged from taking them.
“Bioidenticals” include progesterone, estrogens (estriol, estradiol, and estrone), and testosterone. They have mainly been promoted as a safer, more natural alternative to menopausal hormone replacement therapy (HRT), but they are also claimed to increase energy, well-being, and quality of life, and to have an anti-aging effect. Suzanne Somers recommends them for all age groups and both sexes. There is no evidence to support any of those claims.
The whole “bioidentical” thing is a pseudoscientific concept: it is a marketing term rather than a scientifically meaningful one. Bioidenticals are promoted by celebrities like Suzanne Somers, a few maverick medical doctors like Kent Holtorf, proponents of “natural” medicine, patients who were frightened by the Women’s Health Initiative study of hormone replacement therapy, and critics of Big Pharma. The mainstream scientific community is in consensus: a number of medical organizations, from the American Cancer Society to the Mayo Clinic, have issued statements similar to that of The Medical Letter.