iForce Nutrition Testabolan Review

Testabolan is a simple (three ingredient) “Anabolic Maximizer” by iForce Nutrition…

iForce Nutrition Testabolan



Carnitine comes in a variety of different forms, with Acetyl-L-Carnitine being one of the more bioavailable. Although it has a variety of implications, iForce has included Carnitine in the Testabolan formula because of preliminary research indicating that it can favorably influence (not outright increase) Testosterone.

A 2006 study, this time using mice as the subjects, found that Acetyl-L-Carnitine did not outright increase Testosterone but was effective at preventing Testosterone decline resulting from stress, indicating that Carnitine, similar to Zinc, may help to optimize Testosterone.

Another 2006 study, published in “Medicine and Science in Sports and Exercise”, found that 2g/day L-Carnitine (as L-Carnitine L-Tartrate) for 21 days increased the density of androgen receptors in muscle cells, which would not directly increase Testosterone but may enhance its effects. These findings suggest the same as those of the study involving mice, which is the Carnitine can be effective for maintaining optimized Testosterone levels, but does not outright increase Testosterone.

Assuming two servings daily, Testabolan provides a dose of Carnitine in-line with what has been shown to encourage a favorable hormonal environment.


, 4-Divanillyltetrahydrofuran is a compound which is primarily found in Stinging Nettle, as well as some other related Nettles. Stinging Nettle, in general, is commonly used by bodybuilders in an attempt to block Sex Hormone Binding Globulin (SHGB), a protein that binds to sex hormones (Testosterone and Estrogen), preventing them from entering cells activating their corresponding receptors. Inhibition of SHBG serves as a way of increasing “free” Testosterone, that is, Testosterone that is free to activate Androgen receptors and induce its biological effects. A 1996 in vitro study from the “Journal of Biosciences” found that 3, 4-Divanillyltetrahydrofuran was an effective SHBG inhibitor, but these results have never been replicated in human subjects.

It’s possible that 3, 4-Divanillyltetrahydrofuran can lead to an increase in free Testosterone, but due to a lack of human studies, an optimal dose has not been established. Testabolan contains 400mg of 3, 4-Divanillyltetrahydrofuran, but again, given a lack of human studies, the efficacy of this dose is difficult to interpret.


Naringin is a polyphenol commonly found in Grapefruit and some other citrus fruits which is thought to be one of the primary compounds responsible for the weight-loss benefits of Grapefruit, though other polyphenols are perhaps more potent. While Grapefruit has proven beneficial as a fat-loss agent in multiple studies, Naringin has rarely been studied in isolation.

A 2008 study from “Phytotherapy Research” found that Naringenin (metabolite of Naringin) was able to stimulate peroxisome proliferator-activated receptors (PPAR) activity in vitro, a mechanism which can induce fat-loss via the release of Adiponectin (a protein which facilitates the breakdown of fat). These results lend credibility to the already established notion that Naringenin is one of the main polyphenols responsible for the weight-loss benefits of Grapefruit, noted in several studies, but it’s unclear whether Naringin can induce the same effects (remember Naringenin and Naringin are different compounds).

Naringin has been shown to potentiate the effects of Synephrine, but since there is no Synphrine in the Testabolan formula that doesn’t really matter much. Furthermore, the dose used in this study (600mg) was much higher than the 20mg per serving present in the Testabolan formula.


The direct Test-boosting potential of Testabolan is pretty much limited to a single ingredient, 3, 4-Divanillyltetrahydrofuran, with Carnitine only encouraging an optimal hormonal environment and Naringin having nothing to do with Testosterone at all. Given the speculative nature of 3, 4-Divanillyltetrahydrofuran in the first place, and absolute uncertainty regarding what might qualify as an effective dose, the Testabolan formula is something of a gamble.

Still not sure which Testosterone Booster is right for you?  Check out our Best Testosterone Boosters List! exists to educate the supplement community and seperate the science from the hype.

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