May the Forskolin be with you!

by Douglas S. Kalman MS, RD, FACN
Despite the odd name, Forskolin is not what they remove from the baby during ritual circumcision.

Prior to being investigated for its ability to enhance thermogenesis, forskolin was thought to have many other health-enhancing properties.(1) Forskolin has been found to have benefits as a bronchodilator (thus it may be helpful in asthma and in wheezing) and an anti-inflammatory. It's also been shown to lower blood pressure, enhance the strength of heart muscle contractions, and to prevent blood platelets from clumping together and possibly forming unwanted blood clots.(2-5)

However, if you're reading this magazine, you're probably more interested in its effects as a fat burner. To better understand its potential uses, it's important to review how this herbal is purported to work.

Background
Forskolin enhances one very important enzyme in the body known as adenylate cyclase, which in turn causes a cascade of hormonal and enzyme reactions resulting in fat being burned for energy. To provide you with an overview of how "A" (forskolin) becomes "Z" (liberated fat), a quick biochemistry lesson is required.

The enzyme adenylate cyclase, when stimulated, enhances the production of cyclic AMP, which in turn activates an enzyme known as protein kinase (a building type of enzyme). Protein kinase, in turn, activates hormone sensitive lipase (which is involved in the breakdown of triglycerides) to stimulate the release of fatty acids from body fat. These liberated fatty acids from body fat can be burned for energy, thus helping you lose fat weight.

Forskolin is also known to stimulate the thyroid (specifically, in stimulating the production of T3).(6) The thyroid, of course, is the master gland for deciding metabolism. If you're unlucky enough to have a sluggish thyroid, you'll have a much harder time shedding fat. On the other hand, If you have an overactive thyroid, you'll be able to eat buffet after buffet and still be one ripped bastard.

In short, forskolin burns fat through two different pathways: causing the body to burn fat for energy and enhancing thyroid function.

Research review:
To date, there have been two clinical studies examining the effectiveness of forskolin as a weight loss aid. Neither have yet been subject to peer-review or published in a medical journal. Additionally, according to the company that manufactures and administers the patented form of forskolin, two more clinical studies are being sponsored.(7)
In the first open-field study, six overweight women were given 250-mg forskolin extract twice daily for eight weeks. It's unclear, however, whether or not the 250-mg capsules were of a 10% forskolin extract, which would have provided 25 mg twice per day, but I'm assuming that was the case.

Participants were asked to maintain their normal diet and physical activity levels. To ensure maintenance of physical activity levels, each participant answered multiple questionnaires throughout the study period. The results indicated that the subjects lost an average of 10 pounds and that the weight loss was progressive. That means that as the study proceeded, weight loss continues in a linear fashion.

The researchers also noted that about 80% of the weight lost was fat weight. This aspect of weight loss is damn impressive. When most people lose weight, they lose a significant amount of muscle, too. And, in what may help appease the "kill all supplements" witch hunters out there, the participants experienced no noticeable changes in heart rate and blood pressure.(8) This isn't the best type of research study design, but the results are undeniable.

In another unpublished study, 26 overweight but healthy subjects were randomized to receive an ephedrine plus forskolin supplement or matching placebo for eight weeks.(9) The study measured the effects of the supplement on body weight, body composition, blood pressure, serial EKGs, lung function, oxygenation of the blood, blood sugar, liver and kidney function, the immune system (white blood cells), and other safety factors.

After eight weeks, the group that took the forskolin lost significantly more body weight and fat then the placebo group. In all, from what I can tell, the test group lost six pounds, along with experiencing a reduction in body fat of 2% (along with minimal to zero loss of muscle tissue).

In short, this study wasn't that impressive in terms of weight loss and fat loss since forskolin was mixed with ephedrine alkaloids. And, to be honest, the study might have been better had it also compared the effects of the ephedrine/forskolin with either ephedrine or forskolin, alone.

However, this study and others that are in progress indicate that forskolin is destined to be a supplement that you definitely want in your fat loss arsenal, and kudos to Biotest for including it in their upcoming fat thyroid-modulating product, T2-Pro™.

So, what's the common dosage?
According to the United States Patent for forskolin, the beneficial dosage for fat loss and enhancement of muscle is up to 60 mg per day.(10) Typically, this supplement is provided as an extract ranging from 1-10% forskolin. Therefore, if you see a supplement label that lists 250 mg. of Coleus forskolii at a 10% extract, you're actually getting 25 mg of forskolin.

Concluding thoughts

Forskolin is an exciting fat-loss herb with a motherlode of potential, but the lack of further clinical evidence needs to be addressed. Sure, the empirical and anecdotal evidence is impressive, but we need more hard research.

About the author
Doug Kalman MS, RD, FACN is a Director at Miami Research Associates, a pharmaceutical and nutraceutical research company specializing in Phase II through Post Market Studies. He is a Fellow of the American College of Nutrition and a spokesperson for the American College of Sports Medicine.