The Flawed DHEA Study
A study being circulated in Congress purports that DHEA (dehydroepiandrosterone) is an anabolic steroid. The study measured the effects of very high doses of DHEA that were injected into a hybrid strain of castrated mice. The study used DNA microassays to compare the genomic effects of DHEA, DHT (dihydro-testosterone), and placebo (control) on prostate tissues. At autopsy, prostate tissues of the various groups of mice were weighed to assess anabolic stimulatory growth.
Compared to the DHT group, the prostate tissues of mice injected with very-high-dose DHEA weighed 33% less. Even more revealing was the finding that prostate tissues of an intact control group that received neither DHEA or DHT weighed 24% more than the DHEA group—suggesting that DHEA may have had an anti-anabolic effect in the tissues weighed.
In the four-week arm of the mouse study, the amount of DHEA injected daily was 30 times greater than the DHT dose (0.1 mg of DHT compared to 3 mg of DHEA). In the one-week arm of the study, the amount of DHEA injected daily was 62 times greater than the DHT dose (0.1 mg of DHT compared to 6.25 mg of DHEA). Since the dose of DHEA was 30-62 times higher than the dose of DHT, the effects shown on the gene expression assays are not comparable.
The mice were given extremely high doses of DHEA that exceed what any human would ever take. For example, in the four-week portion of the DHEA-DHT study, the numerical human-comparison dose of DHEA based on weight alone was 5,832 mg, whereas in the one-week study, the numerical human-comparison dose was 16,200 mg.
When calculating the correction factor that extrapolates the conversion value of mice to humans, and then computing the mode of administration given to the mice (i.e., injection), the human-equivalent DHEA dose if taken orally would represent about 15,800 mg a day. Typical human doses of DHEA are only 15-75 mg a day, a vastly smaller amount than used in this mouse study being used to discredit DHEA. In other words, the mice in this study were given a human-equivalent dose that was a startling 316 times greater than what the average dose health-conscious people are taking today to restore DHEA to youthful ranges.
The DHEA dose was even higher in the one- week arm of the study, where the extrapolated human-equivalent dose of 43,910 mg of DHEA was administered to mice. To elaborate, when DHEA is injected, it bypasses normal absorption barriers and degradation by the liver, thus becoming much more potent to the organism.
Based on the egregious overdoses of DHEA used in this mouse study, the findings have no genomic relevance to the 15-75 mg a day of DHEA that humans take. Yet certain members of Congress have been led to believe that this study somehow changes the status of DHEA to that of an anabolic steroid.
The findings of the study used to attack DHEA contradict other recent side-by-side gene comparison studies. These studies refute the notion that DHEA is an “anabolic steroid,” but were not even mentioned in the conclusion of the one biased study being used as evidence that DHEA should be outlawed. It is customary to mention contradictory research in the conclusions of scientific studies in order to provide the reader with a glimpse of other research findings that show different outcomes.
The flawed DHEA-DHT study showed that several genes were modulated by both DHEA and DHT in the mouse prostate and seminal vesicles. However, simply because a number of mouse genes are modulated by both DHEA and DHT does not in any way provide information as to favorable or unfavorable changes in gene expression. For a complete report about why DHEA should not be reclassified as an anabolic steroid drug, log on to www.lef.org/featured-articles/dheafact.