RevTest is RevLabs’ testosterone booster. The formula is pretty simple and consists of some of the most common (alleged) test-boosting ingredients…[Skip to the Bottom Line]
Trigonella Foenum Greacum (also known as Fenugreek) is an herbal extract that has gained traction in the supplement industry as a libido enhancer. However, a 2009 study, published in the International Journal of Exercise Science, found that males who supplemented with Fenugreek extract showed no increase in anabolic hormones (i.e. testosterone). A 2011 double-blind, placebo controlled study found that 6 weeks of supplementation with a Fenugreek derived supplement (Testofen) led to scoring 25% higher on a libido test (sexual arousal and orgasm in particular) than the placebo group, but with no increase in Testosterone levels, meaning that the mechanism of action was not an increase in Testosterone.
So if these studies have concluded that Fenugreek does not increase testosterone, then how has this supplement gained traction? Well, one 2010 study, published in “The International Journal of Sports Nutrition”, found that supplementation with 500 mg of Fenugreek extract (Testofen again) resulted in a significant increase in free-Testosterone levels. Ultimately, the results are mixed, with two studies indicating no increase in Testosterone and one indicating increased Testosterone. More research is needed to clear up this discrepancy, but for now it appears Fenugreek is only reliable as a libido enhancer, not a Testosterone booster.
RevTest contains 350mg of Fenugreek Extract, less than the 500mg used in the one positive study, further limiting the possibility of increased Testosterone. That being said, 350mg may be enough to noticeably boost libido.
Epimedium (also known as Horny Goat Weed) is generally used as an aphrodisiac and libido enhancer, but does possess mechanisms by which it may boost Testosterone. These effects are primarily attributed to the active compound, Icariin.
A 2006 study, published in the “Asian Journal of Andrology”, found that Icariin (80mg/kg) was able to increase Testosterone roughly three times as much as the control group in chemically castrated mice. However, the dose used in this particular study would be roughly equivalent to a 200lb human consuming 1150mg pure Icariin daily. That being said, Icariin has demonstrated varying degrees of efficacy at varying doses, so it is possible that there is a slight influence at the dose present in Isa-Test DA3. At the very least, Icariin supplementation is generally associated with enhanced libido and sexual well-being (providing the illusion of increased Testosterone without the strength gains).
RevLabs does not disclose the amount of Epimedium (or Icariin) in the RevTest formula, though it is likely far less than what was used in the above mentioned studies.
7-Keto DHEA is a metabolite of DHEA which has been investigated primarily with regards to weight-loss and hormone interaction. A 2000 study, published in “Current Therapeutic Research”, found that 200mg of 7-Keto DHEA daily for 8 weeks had no influence on circulating Testosterone in adult males. A 2005 study from “The Journal of Steroid Biochemistry and Molecular Biology” found that several DHEA metabolites, including 7-Keto DHEA, exhibited minimal influence on Androgen receptors.
While 7-Keto has shown no efficacy as a Testosterone booster, it has stronger implications for weight-loss. A 2000 study found that 200mg 7-Keto given to subjects who were on a calorie restricted diet resulted in more weight loss than the placebo group (consuming the same diet) over an 8 week period. A 2007 study, published in “The Journal of Nutritional Biochemistry”, found that 200mg of 7-keto DHEA raised the metabolic rate of subjects on a calorie restricted diet by 1.4%, whereas the placebo group experienced a 3.9% reduction in metabolic rate (the normal reaction to calorie restriction). However the length of this particular study was only 7 days, not long enough to measure weight loss, though this provides a likely mechanism of action for the first (2000) study.
RevTest contains an undisclosed amount of 7-Keto DHEA, but given it is listed second in a 245.4mg proprietary blend, there is likely no more than 100mg.
Zinc is required for the conversion of cholesterol (and other lipids) into sex hormones, as well as the existence of Androgen receptors, as evidenced in a 1996 study, in which rats fed a zinc deficient diet experienced a decrease in Androgen receptor sites and an increase in estrogen receptor sites. So while Zinc deficiency can certainly result in low testosterone, there is no evidence indicating that supplemental Zinc can increase Testosterone above normal. In fact, there is ample evidence to the contrary.
A 2009 study, published in the “European Journal of Clinical Nutrition”, concluded that zinc (ZMA) supplementation had no influence on serum testosterone levels in non-zinc deficient men. A similar failure to influence testosterone via zinc supplementation was seen in a 2011 study, the subjects of which were trained cyclists who consumed sufficient dietary zinc.
However, a 2005 study, the subjects of which were wrestlers, demonstrated that zinc supplementation was able to attenuate exercise-induced declines in testosterone levels. So, the inclusion of Zinc in the RevTest formula will not boost Testosterone, but may help maintain consistently normal Testosterone levels.
THE BOTTOM LINE:
RevTest contains a concise blend of a few alleged Testosterone-boosting ingredients, namely Fenugreek, which is unreliable at best. Though the formula as a whole may be moderately effective at maintaining normal Testosterone levels, it is unlikely that users will experience a notable increase in Testosterone levels (beyond normal). RevTest may increase libido, creating the illusion of increased Testosterone, but most likely won’t convey the increases in strength and lean mass generally associated with increased Testosterone.
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