We all are aware of the profit margins of the weight loss industry. You are always reminded of these figures whenever someone discusses a health supplement.
And indeed they are making a lot of money from extracts found in nature.
A number of herbs and plants are screened for anti-obesity properties in order to devise one such supplement that would melt fat away.
Coleus forskohlii is one such plant. It is a herb used in Ayurveda – traditional Indian medicine.
It is a member of the mint family. Forskolin is the bioactive ingredient present in this herb that imparts the medicinal properties.
It is used to treat disorders of the gastrointestinal, respiratory, cardiovascular and central nervous system.
It is used popularly to treat asthma, glaucoma, allergies, hypertension etc.
Today it is being popularly recommended as a fat burner.
In this article, we are going to investigate what this perennial plant extract can do for those who are looking out for a weight loss supplement.
How does forskolin work?
As you must have already heard forskolin is an adenylyl cyclase stimulator. Adenylyl cyclase is an enzyme that plays a regulatory role.
It converts ATP (a form of energy) into cAMP.
Forskolin increases the level of cAMP – cyclic adenosine monophosphate in the cells.
cAMP is an intracellular signal transducer- it controls the conversation between the cells so that they interact and regulate body functions.
Adapted from: Natriuretic peptides in cardiometabolic regulation and disease, Zois et al, Nature Reviews Cardiology,11,403–412,2014
Increase in activity of cAMP is said to facilitate ‘lipolysis’- break down of fats and utilisation as an energy source.
The image shows how cAMP mediates conversion of triglycerides to free fatty acids.
Lab studies show that higher concentration of forskolin does stimulate lipolysis.
cAMP is known to regulate lipolysis by controlling the activity of enzyme lipase and hormone insulin.
Also, research shows that cAMP levels are impaired in obese individuals.
So scientists hypothesize that forskolin can normalize these levels and this may have beneficial effects on weight loss.
Based on these findings there has been a lot of hype that this all natural extract can cause weight loss.
Forskolin and Weight Loss
The claim of forskolin’s use in weight loss has been studied but only to a limited extent; though its role in increasing cAMP and its possible implications have been widely investigated.
We will be going over the possible links between forskolin and weight and fat loss in this section.
Forskolin stimulates lipolysis- the breakdown of fats
Studies conducted on fat cells report that forskolin stimulates cAMP production and lipolysis.
At high concentrations, it stimulates lipolysis independent of cAMP levels.
Lipolysis is the breakdown of fats into smaller units such that they can be utilised as a source of energy.
When combined with other agents that stimulate cAMP levels it potentiates their activity.
Similarly, agents that suppress adenyl cyclase activity such as insulin, inhibit the activity of forskolin.
What does this mean?
Lab studies show that forskolin increases the levels of cAMP and stimulates lipolysis or breakdown of fats in fat cells, thereby preventing deposition or getting rid of fat stores.
Forskolin’s prevents fat storage
An animal study was conducted to evaluate the effect of forskolin on obesity and metabolic disturbances.
Rats received a ‘cafeteria diet’ and coleus forskohlii extract was given as treatment.
The cafeteria diet led to obesity in animals. Coleus forskohlii extract reduced food intake and prevented weight gain caused by diet in animals.
Another study investigated the anti-obesity effect of Coleus forskohlii in ovariectomized (surgical removal of ovaries) rats.
The extract reduced body weight, food intake and fat accumulation in the animals.
What does this mean?
Coleus forskohlii extract is reported to prevent fat accumulation and reduce body weight and hunger in animals.
It affects the functioning of thyroid- master regulator of metabolism
A study proves that forskolin increases the level adenylyl cyclase by 7 folds at a concentration of 5-10 microM.
Thyroid is the main organ that regulates metabolism, however, the relationship between thyroid hormone and obesity is complex.
It is well established that a sluggish thyroid in case of hypothyroidism can cause weight gain and it is implied that forskolin treatment can help normalize thyroid gland’s activity.
What does this mean?
Research shows that forskolin can affect thyroid activity thereby regulating its role in metabolism and normal or pathological conditions. Since thyroid affects body weight this finding can be relevant in obesity treatment.
Forskolin’s effect on body composition in obese individuals
Whenever the topic of forskolin’s role in weight loss is mentioned, these two studies have to be quoted.
The first one dates back to 2005 where 23 females were supplemented with Coleus forskohlii extract (ForsLean supplements) twice a day for 12 weeks.
No differences in body composition or body fat were observed but the researchers concluded that the extract prevented weight gain.
Reduction in hunger and increase in fullness was observed.
The other study (again conducted in the same year) was conducted on obese men who were given the same supplements for 12 weeks.
Interestingly this time a decrease in body fat, increase in lean mass and increase in testosterone was observed.
However lean mass was also found to be increased in the placebo group.
What is surprising in these studies that despite of the same composition of the supplements the results are contradicting.
Also, these studies were funded by Sabinsa Corporation- the producer of Forslean supplements. No such claims that forskolin boosts metabolism was proven by either of the studies.
Another study conducted in Gujarat Ayurved University, India investigated the efficacy of Coleus forskohlii in hypertension treatment.
Results reported a 2.3-2.6% decrease in BMI upon completion of treatment.
What does this mean?
2 out of 3 studies on humans report that Coleus forskohlii causes a decrease in body weight. But there are a number of caveats which can't be ignored, one being that use of the same supplement caused a loss of weight in one study but did not alter body composition in the other.
It acts as a topical fat burner
A number of creams are being devised with the aim that topical application of this cream can reduce fat depot in that region.
Forskolin is one of the ingredients that make up such topical applications.
Studies conducted on humans report that application of forskolin cream alone and in combination with other components can induce fat loss in women’s thighs.
One study investigating the use of such cream containing forskolin reported the reduction in circumference of abdomen, hips, buttocks, and waist within 4 weeks of twice-daily application.
However, this study was funded by the cosmetic and wellness company and not conducted for educational purpose.
What does this mean?
Forskolin is used popularly used in topical slimming products and is proven to cause fat loss in human studies.
Dosage
No specific dosage for forskolin in weight loss has been ascertained.
As per the studies, a 250 mg supplement containing 10% forskolin twice a day should be consumed for a period of 12 weeks.
A dose of 25-60mg is recommended initially.
Precautions
Conclusive evidence regarding the safety profile of forskolin is limited but the adverse events reported are mild and as follows:
- Gastrointestinal symptoms
- Increased heart rate
- Restlessness
- Upper respiratory tract infections
- Lowering of blood pressure
It should be avoided in case of pregnancy and lactation. It could possibly have drug interactions especially in case of high blood pressure drugs and blood thinning agents.
It is not advisable to take forskolin supplements unless prescribed by a health practitioner.
Conclusion
Forskolin’s ability to prevent fat storage and break down fats has been proven in animal or cell-based studies.
The data available on forskolin’s fat burning capability is limited and premature to make any conclusion that it can be used as a weight loss aid.
Based on the data we have combed through to reveal the facts to you, we would not advise you to take forskolin supplements unless you are advised by a doctor.