What is forskolin?
Forskolin (7 beta-acetoxy-8, 13-epoxy-1 alpha,6 beta,9 alpha-trihydroxy-labd-14-ene-11-one) is the main active ingredient in the Ayurvedic herb Coleus forskohlii. Coleus is a member of the mint family and grows in subtropical areas in India, Burma, and Thialand. Forskolin has been extensively researched in the medical field for use in the treatment of allergies, respiratory problems, cardiovascular diseases, glaucoma, and many other conditions. It has also recently gained popularity as a fat loss agent.
What application does forskolin have?
Forskolin, along with a few select others (such as epinephrine), is the standard substance used in scientific studies when a lipolytic (fat burning) agent is needed (1-4). Unfortunately, few clinical studies have been done on the use of forskolin as a weight loss aid. One uncontrolled study on six individuals with 50 mg per day found significant fat loss, but these results are only suggestive at best, especially since this study was funded by a company that has a patented forskolin product (5). More encouraging are the studies showing forskolin to be effective for topical fat loss (6, 7). Also, despite the absence of clinical evidence, forskolin initiates many procecesses that are known to cause fat loss.
How does forskolin work?
Forskolin works by activating the enzyme adenylate cyclase (1). Lipolytic hormones such as epinephrine (adrenalin) activate adenylate cyclase as well, but forskolin does not have the same CNS effects, so it essentially bypasses the step that is associated with the unwanted side effects (nervousness, restlessness) we find with other fat loss agents that function by increasing lipolytic hormone levels. When adenylate cyclase is activated it then converts to cyclic adenosine monophosphate (cAMP). This increase in cAMP levels has many effects on the body, but the one that is of most interest for fat loss is the activation of cAMP-dependent protein kinase, which in turn activates hormone-sensitive lipase (HSL), which ultimately breaks down fat and releases it as free fatty acids in the bloodstream (1). This process is commonly referred to as the "cAMP cascade" or "lipolytic cascade." On top of all this, there is an added bonus – forskolin also acts as a thyroid stimulant, most likely through a cAMP-mediated process (8).
What other benefits does forskolin have?
* Cardiovascular health - Many studies have shown forskolin, as well as other actives in Coleus forskohlii, to be effective at lowering blood pressure (9), inhibiting platelet aggregation (10), improving heart function (11), and possibly increasing nitric oxide levels (12). All of these effects are cAMP mediated.
* Treatment of specific conditions - As the activities of cAMP are very important in many areas of the body, forskolin is also effective in the treatment of various conditions related to low cAMP levels or high blood pressure, including allergies, glaucoma, asthma, inflammatory conditions, and many more.
Are there any side effects?
There are no major side effects reported in the literature, but you should consult a doctor before using forskolin if you are being treated for any of the conditions listed above as drug interactions may occur. Large doses of forskolin will also probably make one drowsy, as it is an antihistamine. If this becomes a problem, one can reduce dosage, take it in combination with a stimulant, and/or take it before bed.
What form of forskolin is best?
There is a wide variance among forskolin products, primarily in the amount of forskolin the extracts of C. forskohlii are standardized to. Be careful when a product says it contains 250 mg of forskolin, as that may just be 250 mg of a 2% extract. Most of the high quality extracts are 10-20% forskolin.
How should I take forskolin?
The typical dosage of forskolin is 25-60 mg per day divided between 2-3 doses, with 50-60 mg being the ideal range.
What are some good supplements to take along with forskolin?
Since there are still no strong clinical trials supporting the use of forskolin for weight loss yet, it is most commonly used as an adjunct to a weight loss regimen rather than a primary strategy. In studies, it is usually used along with a lipolytic hormone, so it may operate synergistically with a supplement that increases lipolytic hormone levels (such as ephedrine or yohimbine). Some of the best products containing forskolin in an adequate dosage are SAN Tight, ISS Lipovar 8, and Syntrax MM4 (which is popularly used in combination with Guggulbolic for a stimulant-free fat loss combination).
References
1. Morimoto C, Kameda K, Tsujita T, Okuda H. Relationships between lipolysis induced by various lipolytic agents and hormone-sensitive lipase in rat fat cells. J Lipid Res 2001 Jan;42(1):120-7
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11160373&dopt=Abstract
2. Lofgren P, Hoffstedt J, Ryden M, Thorne A, Holm C, Wahrenberg H, Arner P. Major gender differences in the lipolytic capacity of abdominal subcutaneous fat cells in obesity observed before and after long-term weight reduction. J Clin Endocrinol Metab 2002 Feb;87(2):764-71
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11836318&dopt=Abstract
3. Imbeault P, Prud'Homme D, Tremblay A, Despres JP, Mauriege P. Adipose tissue metabolism in young and middle-aged men after control for total body fatness. J Clin Endocrinol Metab 2000 Jul;85(7):2455-62
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=10902793&dopt=Abstract
4. Imbeault P, Tremblay A, Despres J, Mauriege P. Beta-adrenoceptor-stimulated lipolysis of subcutaneous abdominal adipocytes as a determinant of fat oxidation in obese men. Eur J Clin Invest 2000 Apr;30(4):290-6
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=10759876&dopt=Abstract
5. Research Report, Sabinsa Corporation, 1999
http://www.forslean.com/clinical.htm
6. Greenway FL, Bray GA, Heber D. Topical fat reduction. Obes Res 1995 Nov;3 Suppl 4:561S-568S [abstract]
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8697059&dopt=Abstract
7. Greenway FL, Bray GA. Regional fat loss from the thigh in obese women after adrenergic modulation. Clin Ther 1987;9(6):663-9 [abstract]
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=2894247&dopt=Abstract
8. Marians RC, Ng L, Blair HC, Unger P, Graves PN, Davies TF. Defining thyrotropin-dependent and -independent steps of thyroid hormone synthesis by using thyrotropin receptor-null mice. Proc Natl Acad Sci U S A 2002 Nov 26;99(24):15776-81
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12432094&dopt=Abstract
9. Dubey MP, Srimal RC, Nityanand S, Dhawan BN. Pharmacological studies on coleonol, a hypotensive diterpene from Coleus forskohlii. J Ethnopharmacol 1981 Jan;3(1):1-13 [abstract]
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7193263&dopt=Abstract
10. Thivierge M, Alami N, Muller E, de Brum-Fernandes AJ, Rola-Pleszczynski M. Transcriptional modulation of platelet-activating factor receptor gene expression by cyclic AMP. J Biol Chem 1993 Aug 15;268(23):17457-62 [abstract]
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8394344&dopt=Abstract
11. Roth DM, Bayat H, Drumm JD, Gao MH, Swaney JS, Ander A, Hammond HK. Adenylyl cyclase increases survival in cardiomyopathy. Circulation 2002 Apr 23;105(16):1989-94
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11997288&dopt=Abstract
12. Zhang XP, Tada H, Wang Z, Hintze TH. cAMP signal transduction, a potential compensatory pathway for coronary endothelial NO production after heart failure. Arterioscler Thromb Vasc Biol 2002 Aug 1;22(8):1273-8
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12171787&dopt=Abstract
