Dr. Oz doesn't know it but he’s responsible for a lot of the emails I get. For example, in a recent segment of the Dr Oz Show, an herb called Coleus forskohlii (also called forskolin) was said to be one of the secrets to weight loss. I first reviewed Coleus forskohlii in my book a few years ago, but in case you missed that chapter, let’s take a look at this herb and see if I can help you make sense of it. Does it help people lose weight? Let's look at the research and see what we can discover.
What is Coleus Forskohlii?
Coleus forskohlii is a member of the mint family of herbs. Its technical name is Plectranthus barbatus. The roots of the plant contain a compound called forskolin. As such, coleus forskohlii and forskolin are often used interchangeably. Traditionally used in Ayurvedic medicine to treat asthma and other ailments, for the last several years, it’s the claims that forskolin helps weight loss that has sparked people's interest the most. I've even seen Dr. Oz say “it works” when talking about forskolin.
Supplement Tip. If the name of the supplement contains the prefix “fors” or forsk” (or something similar), it probably contains coleus forskohlii.
Coleus forskohlii has been in some products I've reviewed on this site. Some of those have included:
Among others. See those reviews for additional information.
Coleus Forskohlii And Weight Loss
How does Coleus forskohlii help weight loss? Or rather, what is the theory behind how it’s supposed to work? This will get a little technical but bear with me, I promise to bring it home at the end.
Coleus forskohlii stimulates the production of a molecule called cyclic AMP (cAMP). In our body, cyclic AMP helps our cells talk to each other. When an increase or decrease in cAMP is detected, it acts as a signal that causes the body to do something.
One of the things that cAMP does is tell our cells to increase in an enzyme called hormone-sensitive lipase—which burns fat. cAMP might also appears to stimulate the release of thyroid hormone which also helps burn fat and calories.
Translation: Coleus forskohlii (Forskolin) stimulates fat-burning enzymes and hormones which, in turn, causes weight loss.
The theory sounds good but is there any proof? It turns out there are a couple of Coleus forskohlii weight loss studies. Let’s take a look at them now.
Coleus Forskohlii Weight Loss Research
One study from 2005, titled Body composition and hormonal adaptations associated with forskolin consumption in overweight and obese men was published in the journal, Obesity Research.
This study looked at 30 overweight and obese men. Half of these men received Coleus forskohlii and half received a placebo. The people in this study took 250 mg of a supplement – called ForsLean that had 10 % Coleus forskohlii. They took the supplement twice a day (so 500 mg total per day). The study lasted 12 weeks.
ForceLean is a patented extract from the Sabinsa Corporation. ForsLean is in many coleus forskohlii products.
Body fat was determined via DEXA, a very accurate body fat measurement technique that uses x rays.
Study Results
Those people getting Coleus forskohlii showed a reduction in body fat as well as an increase in testosterone.
Study Problems
Lean body mass (I take this to mean muscle) increased as well– but lean body mass also increased in the placebo group too. This could be a
problem with the study.
While lean body mass did increase more in those getting the Coleus forskohlii extract, how did the placebo (which should, in theory, do nothing) also increase lean body mass? This is a problem. The people in this study did not exercise. So if exercise didn’t cause the increase in lean body mass what did?
Another problem is that the people in the Coleus forskohlii group had higher testosterone levels at the start of the study than those in the placebo group. If the people were randomly divided into two groups, one would think that testosterone levels would be pretty much the same between the groups. But they were not.
This doesn't make sense.
As such, I'm not sure if coleus forskohlii raises testosterone or not.
Another observation was that Coleus forskohlii did not increase metabolic rate. This contradicts “experts” on the Dr Oz Show who have said that forskolin raises metabolic rate.
This particular study gets mentioned a lot on bodybuilding websites, however given the problems I just listed, I’d like to see another study to confirm these findings.
Another study, titled Effects of coleus forskohlii supplementation on body composition and hematological profiles in mildly overweight women was published in 2005 in the International Journal of the Society of Sports Nutrition.
In this study, 19 women were given a Coleus forskohlii supplement –ForsLean – which contained 250 mg of a 10% Coleus forskohlii extract. The supplement was taken twice a day (so, 500 mg total per day was taken). The other group received a placebo, and the study lasted 12 weeks.
Body fat was determined via DEXA scan which is a good indicator of body composition.
Study Results
This study found that Coleus forskohlii did not promote any significant weight loss but it did seem to reduce the gaining of weight.
The forskolin extract did not seem to change thyroid hormone, liver enzymes, cholesterol, insulin, heart rate, blood pressure or red or white blood cells. This study, unfortunately did not measure testosterone levels as the study above did.
So, while the Coleus forskohlii extract didn’t seem to help weight loss, it did appear to help people from gaining weight.
It is interesting supplement used in this study (ForsLean) is the same as that tested in the previous study. So, two studies on the same supplement each found different outcomes.
These two human studies of Coleus forskohlii and weight loss appear to contradict each other in terms of whether Coleus forskohlii helps weight loss or not.
Based on this, maybe forskolin helps weight loss, or maybe it might reduce the rate at which people gain weight. So which is it? I don’t think anyone has the answer at this time. This is a far cry from the proclamation of Dr Oz, who said on his TV show, “it works”.
In a 2014 study, coleus forskholii was shown to curb appetite in rats fed a “cafeteria diet (basically, they fed rats a lot of junk food). That's interesting, and in theory, by curbing appetite, it might reduce gaining weight, which the previous study mentioned above noted. Still, this should be shown in human studies to know better what's going on.
Which Coleus Forskohlii Supplement Is Best?
There are a LOT of Coleus forskohlii supplements out there. As such, finding what may be the “best” can be daunting. So let me see if I can make the process a wee bit easier for you.
Some products make vague claims such as “raising metabolism” or boosting testosterone levels. But, from this review, claims like these are on shaky ground. As such, I recommend avoiding products that make claims like these.
Also avoid any ForsLean product that refers to Dr Oz. He has said this on his TV show too.
Remember coleus forskohlii and forskolin are the same thing. Different supplement companies call it by both names. Some brands may even call it by its scientific name: Plectranthus barbatus. This is important because this might confuse some people.
Most of the research is on the ForsLean brand.
Forslean is found in various coleus forskolii supplements either alone or in combination with other ingredients.
If it's going to work, ForsLean is the only ingredient that should be needed. There should be no need to combine coleus with
or any other trendy ingredients.
While studies often use 500 mg per day, given the lack of human research, its hard to know if this is the correct amount. As such, start with less to see if that works with you.
Coleus Forskohlii Side Effects
Based on the human studies done so far, Coleus forskohlii (forskolin) seems to be pretty safe in healthy people for at least 3 months.
Here are some things to consider when taking this supplement. This list is not complete.
- Start with less than is recommended for the first week to see how you respond.
- Some research using mice has noted coleus forskholii might alter an enzyme system called P450 which is involved in metabolizing a variety of medications. Because of this, people who take any medications should ask their pharmacist or doctor and specifically ask questions relating to the P450 enzyme system. Your doctor /pharmacist will know exactly what you are talking about when you say “P450 enzyme.”
- Little research involves people who are not “healthy,” and the herb may interact with medications like blood thinners. People with serious health issues like heart disease etc. should speak to their doctor before taking Coleus forskohlii.
- Stop all supplements at least 2 weeks before surgery.
- Speak to your doctor if you are pregnant or breastfeeding.
Does Coleus Forskohlii Work?
Despite the hype, I feel more research is needed to know if coleus forskohlii (forskolin) really works or not. As more research is done, we will have a better if it works. The research on forskolin is intriguing, but it is far from conclusive. I do think coleus forskohlii is an interesting supplement, but I can't yet say either way whether it helps people lose weight or not because I want to see a few more human studies.
If you have tried it and it helped you or not, I hope you will leave a comment below.
Here is coleus forskohlii on Amazon
Hi, My husband and I have been taking the Forskohlii 20% with the 7-Keto for about 3 weeks and I have lost 10 lbs and my husband lost 15 lbs. We also work out 6 days a week. But before this we would work out and could not loose anything. My hips and thighs are slimmer.
It is also slimming our stomach to. I feel that this works great for us. But I think the combo of the pills and working out is the trick, at least for us it is.
Is there any studies that compare healthy adults that work out heavily? I’m a hard core Crossfitter, follow the Zone eating plan, and I am looking to dispose of some body fat that just doesn’t seem to want to leave. Any input here?
Daniel, compare coleus to working out? not that i can remember. since you mentioned cross fit, do read my review on rhabdo and be sure to also read the comments at the end…
http://www.joe-cannon.com/rhabdomyolysis-personal-trainers-exercise-review-symptoms-negatives-eccentric-fitness-bootcamp/
I love your views Joe!
Great blog….for a student.
thanks Nafeesah !
Hello,
I just turned 45 and weigh 138 pds. I am 5’3. I started Coleus Forskohlii (ForsLean) yesterday and hope to find some results of my own. Thank you so much for all the information you provided. Very interesting on how many benefits there are..let’s see how it works for me. I’ll keep ou posted.
Diane thanks ill look forward to your updates!
While I did not see the Dr. Oz show spoken of, there seems to be a couple of key elements missing when referring to the supplement and the endorsement. Forskolin is a SUPPLEMENT not a replacement for proper diet and exercise. One can’t expect to take a “miracle” pill and keep eating cheeseburgers and french fries. The endorsement clearly states “as part of a proper diet and regular exercise”, in all the comments here people are keeping the same diet and not exercising.
Also remember that this are “person” specific, some of us have a naturally high metabolic rate while others have slower ones. Forskolin is proven to stimulate the thyroid which in turn speeds metabolism. If exercising regularly and having a balance diet the weight loss will come, you have to put in the effort. You can’t rely on just pills alone.
I’ve been taking 250 mg twice a day. 2-weeks now. I’m loving it. because it has no caffeine n It seems to bring my blood pressure down, n I feel full with a lot of water after. Most supplements for weight loss, I’ve tried, work well with Diet n exercise, but, they make me Too hot! n increase my blood pressure not safe! I know this is working for me! B/c I ate a lot Of chocolate this week: Halloween. N in general I eat Lean n almost vegetarian but eat too much chocolate and my stomach getting lean! I will check back next month before thanksgiving! Thank U all for your comments! CIN-D
curious CIN-D how things are going for you now? its March have you lost anymore weight?
I saw the Dr. Oz show also. I couldn’t find the forskolin at first. I went to Swanson.com and finally found it. I have been taking 1 pill at am like Dr. Oz mentioned for 2 months now. I haven’t lost any weight yet. I have gotten a bladder infection which I haven’t had one for years. I also have a low thyroid.
The doctor had to increase my meds. I don’t know if the forskolin had anything to do with either one. I notice that you said you have to have 20% works. I have been taking only 1 pill a day so that is only 10% Forskolin. I am increasing to 2 pills a day. I have a bottle and a half left. If the doctor up’s my meds again I will go off the Forskolin right away. First time I have been on this site. Very helpful information.
Nancy, glad you found me! At this point Im not sure how much coleus might help weight loss and I am even skeptical that it works at all. In the 20% study, remember that they only seemed to show that coleus might reduce gaining weight. They didn’t see any weight loss. Did you mention to your doctor you were taking Coleus? I did look up coleus and thyroid and this seemed to be the best website I saw – univ of maryland
I dont know if this helps. Do tell your doctor your taking coleus.
Thank you so much for this information on thyroid. It has helped me a lot.
Debbie, you are very welcome 🙂
Just bought this at health food store then did not research. Will let you know how it works.
I just wanted to say thank-you. Dr Oz points out a lot of herbs, and it gets real confusing. Now I know what words to look for when a supplement really works on weight loss. You can’t buy all the herbs and supplements Dr. Oz talks about for weightloss. LOL
Miriam, thanks Im happy I was able to help you. Have a great day!!
Hello…I too saw the show on Dr. Oz and of course went out and bought Forsaklin and the 7Keto. I have been taking it for the past 3 weeks and I don’t have time to exercise much, but I did lose 4 lbs. I don’t know if its the pills or not but I haven’t changed my diet at all.
Very interesting site.
Hi, Joe,
My husband bought a bottle right after the Dr. Oz show. He started taking Coleus Forskohlii right away. I am not a pill type person, so I have been waiting to see where this goes.
I think the old saying “If it sounds too good to be true, it probably is” applies here. My research did bring me to your blog though, so I am looking forward to future postings.
Joni
I belive most licensed pysicians would not globaly “prescribe” a substance that had a significant effect on the human body. There might be liablity issue. I find Dr. Oz’s “Mr. Science” demonstrations insulting.
My first time on your sight. Think I’ll subscribe. Thank you for the blog.
Zede, Glad you found me and its a good point you make about globally prescribing things on TV.
My wife and I have been using a 10:1 Forskolii extract 250 mg a day. My wife noticed my stomach fat was reduced. I have been working out 4 times a week also. I have noticed and believe it has the desired effect on me.
Please note. The test was for 10% Coleus Forskohlii. Dr Oz mentioned it needed to be 20%. Anything less would not show the results people expected.
Sandy, you may be right – I may have missed him saying that – but I’d still be interested in knowing where Dr Oz came up with the “20% works” statistic.
It was 10%
It does say 20% on the website but I wonder what the difference would be between the 10% and 20% or if it really makes a difference.
Jacqui, good question and I’m not sure.
I tried taking it this week and gained weight! I wonder what is a fair trial.
Audrey, did you watch what you ate too? How was your appetite when wised it? Any different?
According to the Oz show you take one 125 mg tablet of 10% Forskilin. Anything else won’t work. The studies cited use 250 mg.
Scott, ok so ask Dr Oz where he got that information from? Where is the study showing 125 mg of 10% forskolin works best? Show me and I’ll be glad to update my review.
I too saw Dr. Oz premote the Forskolin Slim and purchased a couple bottles. the first two weeks of taking the supplement i gained 10 lbs!!! Was not pleased but figured id try it a bit longer and i have taken it for a month now and have only lost 3 lbs but i also workout 6 days a week am not to happy with the 10% it works theory.
I saw Dr. Oz’s show today. I went to check it out at the store and decided against it. Dr.Oz’s show is always trying to get you buy this, use that, I’m just not to sure about him any more.
Carey, I understand. I sometimes scratch my head over recommendations also.
Personally I think Dr Oz is a bone head! He is clueless and will stand up there and try to sell anything regarding weight loss to suck people in for his own benefit $$$!!
I saw that Dr. Oz show and purchased a bottle, but after I got home, I did some research and found that the side effects -potential stomach bleeding wouldn’t be worth it since I’ve had some stomach ulcers. I think it is irresponsible of Dr. Oz to promote this stuff without talking about side effects. I haven’t opened the bottle and still have the receipt and hope that Whole Foods gives me a refund.
I like the way you write… very down to earth and unbiased.
Leela, thanks for the compliment. I appreciate you saying that! I’m about to post a review on Raspberry ketones which Dr Oz called a weight loss “miracle”. It should be on my site soon.
Hi Claudia, the blood thinning effect is one of the most common potential side effects I see in supplements. I usually mention it because many so people take blood thinner meds and they need to know about this interaction.
when you say sea berries, did you mean sea buckthorn?
In general, I like getting nutrients from food because they have a more broad spectrum of nutrients. I all edible berries are good choices. I add berries -blueberries, strawberries etc to every smoothie I make with my Vitamix.
I saw this show too and agree, that from what I read there was not a lot proof. Silly me, I bought it and then did the research. I have not been taking it because, I read about some side effects that were concerning and did not see and other benefits than perhaps not gaining as much were worth it. It seems odd the both this and the Sea berries both thin blood. I fell like the berries are worth a try because of the other benefits. Since they have omega 3 and A,C,E etc. in it I though I may be able to cut back or replace some supplements with the berries? What do you think?
Frosty, While unconscious bias is always possible, I tend to give researchers the benefit of the doubt when it comes to “rigging” studies. I think most researchers really try to do the best job they can, but I also know that no study – even peer reviewed studies – are “perfect”.
I can tell you that the company that makes the supplement used in the studies -ForsLean – at least partially supported the study (donating product) but the researchers (in the 2nd study I reviewed if I remember) did stipulate they had no conflict of interest.
That said, the study which found forskolin raised testosterone etc. did look a little odd to me and why I’d like to see it duplicated by others.
I’m curious as to why the study groups in the two trials were separated out as males in the first, and females in the second?
I’m also wondering if the difference accounts for the two different outcomes.
I would also suspect that the first study was somehow biased–therefore the outcome was perhaps a bit pre-determined? In other words, rigged.
I’ve been taking 500mg of coleus forskohlin for a week and walking twice a day. I’ve lost 7 pounds. I have a sluggish thyroid and ordinarily find it nearly impossible to lose weight
Which brand do you take?
I THINK THE REAL REASON THE CURE WORD IS AVOIDED IS THAT BY LAW–ONLY A DRUG CAN CURE–SO THE CURING OF AN AILMENT WITH NATURAL MEANS–EVEN AN APPLE— WOULD BE PRACTICING MEDICINE UNLICENSED—STUPID????—-OF COURSE—