Can OTC estrogen supplements like Estroven damage a persons thyroid?

Question

Can OTC estrogen supplements like Estroven damage a persons thyroid?

Answer 1

It is extremely unlikely that Estroven would damage a woman's thyroid gland.  Soy, taken excessively, and all other members of both the legume (pea and bean and pulse) family plus the Cruciferae family (Broccoli, Cauliflower, Turnips, Radishes, Mustards, Brussels Sprouts, et al) can both have a depressant effect on the thyroid gland.  I am unclear however, that the amount of soy isoflavones at or in this product's recommended dosage are enough to have that depressant effect on T3, T4 or thyroxin.  I would probably be actually more concerned that the soy not be GMO, and would like to see the certification for this on the box, or in the product informational materials.

This is the language taken from Estroven's own website:  "Safety of Estroven's Ingredients

The two primary ingredients in our products — isoflavones and black cohosh — have long and safe histories of use. A well-known and well-reputed vendor, Archer Daniels Midland Company, supplies the soy isoflavones used in our formula. In addition, there have been a number of clinical studies about the safety of isoflavones, as well as their positive and protective effects on cardiovascular and bone health.

There has been much safety research done on black cohosh. It is important to note that the kind of black cohosh used in Estroven® products is cimicifuga racemosa, the actual North American herb, rather than the Asian variety, which may not have the same degree of purity. Also, black cohosh does not have the same action in the body as estrogen, which means that it can be used by women who cannot take synthetic estrogens.

Other ingredients used in Estroven® include vitamins and minerals, all of which fall below the Safe Upper Limits as defined by the federal government, as well as various other herbs, which have a similar safety profile to isoflavones and black cohosh.

Using Estroven® with Synthetic Hormones

Estroven® contains phytoestrogens, or isoflavones, natural substances that can be taken safely with hormone replacement therapy (HRT). Phytoestrogens work with your body to support hormonal balance naturally, gently, and safely. Please consult your healthcare professional before taking Estroven® products with HRT.

Using Estroven® with Other Prescription Medicines

Although there are no known significant side effects associated with the recommended use of Estroven® with prescription medications, your medical history plays an important role in the effect that supplements have on your body. Please contact your healthcare professional before using Estroven® with other prescription medicines.

Potential Allergens in the Estroven® Formula

Estroven® does not contain artificial dyes, colors, preservatives, flavors, yeast, wheat, gluten, lactose, or animal products. Estroven® does contain soy, and a small percentage (about 3%) of the population is allergic to soy. Please consult your healthcare professional before taking Estroven® if you have any known allergies.

As with any nutritional supplement, please consult your healthcare professional before taking Estroven®."

So the answer to your question is, "I suppose it's possible, but it's EXTREMELY unlikely."