Forskolin: Boasts long-term health benefits?
If you’re in-tune with what’s hot in the weight-loss industry, you’ve surely heard of forskolin. Supplement manufacturers and marketers claim it will safely help you shed fat and build muscle. We have good news- they’re our first sponsor for the annual AYC Caribbean Tour. So what is natural forskolin, exactly, and does it really work?
Forskolin is an extract derived from the Coleus forskohlii plant, which is native to India. Originally used by cell biologists to manipulate metabolism in cells in the lab, it’s now been adopted as a weight loss supplement because of its direct link to activating and stimulating cylic-AMP levels.
Proponents cite its metabolism-boosting properties as its mechanism of action: pump up cellular metabolism, the logic goes, and fat oxidation will go up. The question is whether the well-established metabolic benefits of forskolin in the lab translate into results in the real world along with proper human dosing for optimal health effects.
Looking at lab rats
The first step from moving from cells in a Petri dish to a full human being is testing the effects of forskolin in a smaller animal. Research from the early 1980s confirmed that forskolin’s fat-burning properties extend to living, breathing creatures: a 1982 scientific paper by Ren-jye Ho and Qi-Huang Shi at the University of Miami School of Medicine described how forskolin acts on specific enzymes in fat cells in lab rats to increase the rate of fat breakdown, or “lipolysis” (1). Another paper published the same year in the journal Molecular Pharmacology found similar results: forskolin had a definite fat-burning effect when administered to lab rats; it kick-starts their cellular metabolism to increase fat oxidation (2).
Knowing this, the question becomes, “can using forskolin long-term actually reduce body fat?” As scientists tend to do, they looked to small animals first. Using female rats with their ovaries removed (a common lab technique to induce obesity in rats), researchers Li-Kun Han and colleagues at the Prefectural University of Kumamoto in Japan found that the rats who were given forskolin tended to eat less, weigh less, and accumulate less fat (3).
Studies in humans
The next logical step is to move to humans. There are two studies on forskolin in humans, but they’re both fairly small. A 2005 study published in the Journal of the International Society of Sports Nutrition followed 19 overweight women for a period of 12 weeks (4). The women were split into two groups; one took 250 milligrams of 10% forskolin extract twice daily, and the other took a placebo.
After 12 weeks, the women in the forskolin group had gained slightly less weight, but this trend didn’t reach statistical significance, so it’s impossible to say whether this was truly the result of the forskolin supplement, or just random chance. The authors did note, however, that forskolin produced no statistically significant negative side effects either, providing a good case for its safety (at least over a short period).
Somewhat more promising results were found in an article published the same year by Michael P. Godard, Brad A. Johnson, and Scott R. Richmond at the University of Kansas (5). This study used a similar protocol: 30 men were split into two groups, one of which took a 250 mg 10% forskolin extract supplement twice every day, and the other took a placebo. This time, after 12 weeks, the men in the forskolin group had lost a significant amount of fat mass. Their actual body weight did not go down, however, because they’d gained muscle mass at the same time.
Godard, Johnson, and Richmond hypothesized that testosterone levels had something to do with this intriguing result. Luckily, they had the foresight to measure the men’s testosterone levels before and after the study. The researchers found that the men who took forskolin had higher levels of free testosterone in their blood, which might explain the increase in muscle mass.
The results of Godard, Johnson, and Richmond’s work, plus the lack of statistically significant results in the previous study on women, might suggest that forskolin interacts differently inside a man’s body versus a woman’s. This, however, is just a hypothesis, and needs more research to confirm.
There is one important thing to note about both human studies: though they were conducted by different research groups, both were funded by the Sabinsa Corporation, a New Jersey-based company that prepares dietary supplement formulations (6). Sabinsa Corporation does not retail forskolin directly to consumers; rather, it supplies the raw materials (i.e. forskolin extract) to vitamin and supplement marketers, who then sell to consumers.
In any case, it’s clear why Sabinsa Corporation would have a vested interest in the outcome of these studies. This does not necessarily mean the results are invalidated: the actual studies were conducted by academic scientists, and the papers still had to go through the standard peer-review process. But it’s widely known that commercially-sponsored research, especially in the health and pharmaceutical realm, is more likely to result in biased results (7).
If trying to piece together all this research into a coherent narrative feels like a daunting task, you’re not alone—physiology researchers have similarly felt there’s more research that needs to be done before we can make a definitive call on forskolin. A 2011 review article by Asker Jeukendrup and Rebecca Randell at the University of Birmingham in the United Kingdom reviewed the evidence supporting forskolin and noted that “although there is a theory that is promising, […] more work is required before forskolin can be recommended” (8).
Similarly, a team of over 20 scientists led by Richard B. Kreider authored a research review in 2010 for the International Society of Sports Nutrition that classified forskolin as “too early to tell”—meaning there’s not enough evidence to say for sure whether or not it works (9).
Should you give forskolin a try?
Though there’s quite a bit of basic research on forskolin that shows it has some potential, ranging from cells under a microscope to tests on lab rats, there hasn’t been enough good, independent research in humans yet to give it an unqualified recommendation as a weight-loss or fat-burning supplement.
It does appear to be safe, and early evidence hints that it might be more effective in men than women, but the jury is definitely still out on the finer points of forskolin’s effects. If you decide to give forskolin a try, it would be best to stick to the protocols followed by the scientific studies described earlier: 250 mg of 10% forskolin extract, twice daily.
Remember, even if it “works,” your weight probably won’t go down. If forskolin does indeed burn fat, it also builds muscle mass as well, so you can’t use the scale to measure your success.