Researchers find Unlabeled Tamoxifen in Body Building Supplement
British researchers have found varying amounts of the estrogen-blocking breast cancer drug tamoxifen in three out of four bottles of Esto Suppress supplements.
About the Bodybuilding Supplement Study
According to MedPage Today, British researcher Micael Evans-Brown, PhD, of the European Monitoring Center for Drugs and Addiction, and his colleagues found high amounts tamoxifen in three-quarters of Esto Suppress supplement bottles purchased on four different occasions between 2011 and 2012.
The researchers noted that the amount of tamoxifen found in the supplement varied from bottle to bottle and ranged from .9 mg per capsule to 3.8 mg per capsule.
At the suggested dose of two capsules per day, consumers would consume 7.6 mg of tamoxifen per dose. Comparatively, clinical doses of tamoxifen for the treatment of gynecomastia (abnormal breast size in males) range from 10 mg to 20 mg.
The presence of temoxifen was not addressed on the product's label.
Supplements Largely Unregulated
“Often the substances are not listed on the labeling, and products may be marketed as ‘natural,’ exploiting the belief that they are safer and healthier options.” – Study authors as published by MedPage Today
More and more studies indicate that manufacturer of dietary supplements often fail to list all the products ingredients on the products’ labels. Conversely, other products were found to be lacking their designated ‘active ingredients’ entirely.
However, due to loose restrictions and a general lack of regulation from federal regulatory agencies, these products continue to market themselves as safe, effective and often ‘natural’.
Body builders may be at an increased risk, according to MedPage Today, as they often actively seek out investigational compounds that have yet been approved for market.
Side Effects of Temoxifen
- Liver failure
- Cerebral infraction