Review: Biotest Carbolin-19…Is Carbolin Better than Anavar?

Posted By elissa on Nov 20, 2007 | 2 comments

“Bottom line, Carbolin 19 can deliver better results than Anavar but without any of the negative side effects, making it the perfect anabolic bridge!”

Can a dietary supplement like Carbolin 19 give better results than an illegal anabolic steroid? Biotest would certainly like us to think so.

Carbolin-19 is colforsin 1,9-ethylcarbonate, which is a derivative of forskolin. Forskolin (aka colforsin) is the active compound in the ancient Ayurvedic medicinal plant, Coleus forskholii.

Coleus forskholii has traditionally been used to treat a variety of disorders, such as heart disease, insomnia and asthma. In recent years, however, it’s been promoted as a fat loss agent—most notably by the Sabinsa Corporation, which holds a patent on Forslean®, a standardized Coleus extract used in various fat loss supplements. Beyond helping with fat loss, it’s also claimed that forskolin can help increase lean body mass.

This is what some bodybuilders take Anavar for. So Biotest assembled some data to prove Carbolin-19 works even better.

One of the members of our research group conducted a university study on an earlier, less-potent version of Carbolin 19. The findings show that pure colforsin literally equals the anabolic effects of Anavar.

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Here’s a chart that compares pharmaceutical-grade colforsin to Anavar. The data for Anavar came from a compilation of two peer-reviewed studies found in the scientific literature. The colforsin data is from the university study that’s pending publication.

As you can see, colforsin blew away Anavar, both in lean mass gained and fat mass lost! And remember, the version of colforsin used in the study is much weaker than Carbolin 19! In addition to being more potent, Carbolin 19 has a longer active life and a substantially greater bioavailability.

Looks like Biotest has done its homework—it’s hard to argue with peer-reviewed studies. Nonetheless, it pays to read the fine print. Let’s take a closer look at Anavar, forskolin and those published studies.

For starters, Anavar (oxandrolone) is considered to be a fairly weak steroid. In Anabolics 2006, author Bill Llewellyn notes that it was designed to be “…an extremely mild anabolic, one that could even be safely used as a growth stimulant in children.”

In other words, Anavar isn’t the sort of drug that yields very impressive results in the first place. Steroid expert Bill Roberts describes it as “…somewhat effective, but not dramatically so, and not a preferred regimen.”

The Biotest ad does not tell us which “two peer reviewed studies found in the scientific literature” were used for the Anavar comparison, but it provides some details we can use to make a pretty good guess.

The studies were 12 weeks long; used 20 mg doses and 100% male subjects. After searching though PubMed and excluding papers using subjects with various disorders/injuries, we’re left with only a few papers on Anavar’s effects on older (> 60 year old) men.

In one study, the average age of the subjects was nearly 73!

Needless to state, studies on older men at risk for metabolic syndrome and sarcopenia are less than ideal for drawing conclusions relevant to bodybuilders.

And the colforsin study…?

As it turns out, the study conducted by “our research group,” was actually performed by Michael P. Godard, Brad A. Johnson and Scott R. Richmond of the University of Kansas. Their study, “Body Composition and Hormonal Adaptations Associated with Forskolin Consumption in Overweight and Obese Men” was funded by Sabinsa—not Biotest—to test ForsLean. The ForsLean extract used in the study was standardized to 10% forskolin—so it was not “pure colforsin,” as claimed in the Biotest ad.

Additional study details appear in a second Biotest article, titled “Dramatic Carbolin-19 Study!” Most of the study numbers are reported accurately, although interestingly enough, the testosterone numbers are not. The article proclaims:

“The Testosterone of the colforsin group rose 33.7 percent, while it decreased 18.35 percent in the placebo group.”

But this is incorrect. The study authors actually wrote:

“The percentage difference among groups that occurred between the initial and final measurements for total testosterone was 16.77 ± 33.77% for forskolin vs. –1.08 ± 18.35% for placebo.”

The Biotest article substitutes the standard deviations for the actual averages, and portrays each value going in only one—preferred—direction. This makes the results look better than they really were, for a parameter most bodybuilders want to increase.

It looks as if Biotest played a little fast and loose with the study description and results. Dr. Godard agrees. In a recent e-mail exchange, he wrote: “I in no way condone or support the inaccurate claims or associated claims that are made by Biotest in regards to my research.”

So much for Biotest’s sales pitch.

Regardless of Biotest’s spin, the question remains: is Carbolin-19 a good supplement for bodybuilders who want to lose fat and gain muscle?

Cell culture studies have shown that forskolin stimulates lipolysis (breakdown of stored fat) via activation of an enzyme called adenylate cyclase. In theory, then, it should boost fat loss—as seen in the study by Dr. Godard and his colleagues. There are a few other studies, however, that show less dramatic results. An example is another Sabinsa-funded study, “Effects of Coleus Forskohlii Supplementation on Body Composition and Hematological Profiles in Mildly Overweight Women.” This paper did not find any significant changes in lean mass or fat, although the researchers did conclude that ForsLean “…may help mitigate weight gain.”

Thus, the information we have on forskolin is positive, but results vary from study to study.

In addition, the data we have in humans was obtained using ForsLean, not purified forskolin. Of course, since forskolin is the only active compound we know of in Forslean, this probably doesn’t matter… It’s reasonable to assume that an equivalent dose of pure forskolin would give similar results.

On the other hand, the forskolin in Carbolin-19 isn’t identical to that in ForsLean. Biotest has made a chemical modification.

We spent the last year extracting and purifying colforsin to pharmaceutical-grade standards and further refining it into a carbonate ester. This reaction extended the duration of action from four hours to 12 hours. The carbonate gave us an increase in bioavailability as well, but it wasn’t enough. So, we incorporated the compound into our Nano-Dispersed Gel, which improved bioavailability to the point of being drug-like.

Does the esterifcation really increase forskolin half-life and bioavailability? No idea. There’s no way to make an independent judgement. Biotest offers no proof for these claims, and there are no studies or other sources of information available. For all we know, it may yield results that are the same, better…or worse than ForsLean.

When in doubt, it helps to consider user feedback. Unfortunately, the comments I’ve seen on Carbolin-19 on various boards make it difficult to reach a conclusion. Some feel it’s helped…others don’t.

In the end, what can we conclude about Carbolin-19?

I think it’s fair to say that forskolin has some promise. In my estimation, it might give a helpful “nudge” to someone already moving in the right direction with his/her diet and workout program. As such, Carbolin-19 could be worth experimenting with—although potential users should bear in mind that the results are likely to be more subtle than implied by the hype.