Is there something out there that can help us lose weight? Ideally, something instead of "eating less and exercising more." As a compromise, we might even accept something that would enhance the effects of eating less and exercising more. In this blog, we have already checked out yohimbine and forksolin for weight loss but they did not make the cut for evidence-based weight-loss interventions.
In this article, we will look at Caralluma as we continue the search for the Holy Grail of weight loss.
What Is Caralluma Fimbriata?
Caralluma Fimbriata, also known as Caralluma cactus, Makad Shenguli and Ranshabar. It is an edible cactus.
Over 260 distinct species of the genus Caralluma (Family Apocynaceae) have been identified and it grows well in tropical Asia and the Mediterranean.
It is described as a "succulent cactus" and is used in preserves such as chutneys and pickles. It is eaten on a daily basis as a vegetable in the Kolli Hills of South India.
Caralluma has been used in traditional medicine in China, India, Iran, and Pakistan for centuries and is used in the treatment of a wide range of conditions including rheumatism, diabetes, leprosy, paralysis, infections, ulcers and pain relief (1).
Pharmacological analysis shows that it contains pregnane glycosides, flavonoid glycoside, flavones, magastigmane glycosides, pregnane steroids, steroidal glycosides, saturated and unsaturated hydrocarbons, aromatic and nonaromatic volatile compounds, and β-sitosterol (2).
Of special interest to us are the pregnane steroids. Phytochemical analysis shows that carraluma contains about 12% of pregnane glycosides (3). Pregnane steroids are also found in African hoodia which is commonly promoted as an anti-obesity and appetite suppressing agent.
Some researchers have suggested that the presence of pregnane steroids in caralluma is indicative of its likely anti-obesity and appetite suppressing properties (2). Let's see if this is the case.
The two main uses of Caralluma in popular medicine relate to weight loss:
- Decreased appetite with the aim of losing weight and
- Weight loss in Prader Willi syndrome.
Prader Willi is a genetic disorder that presents with hypotonia (poor muscle tone) and a failure to thrive during infancy (4). With age, people with Prader Willi are noted to have other features such as short stature, food-seeking behavior with excessive weight gain, developmental delay, cognitive disability, and behavioral problems. There is considerable interest in helping to curb appetite in order to control weight in affected individuals.
There are 56 caralluma related products for sale on Amazon and the average cost of a 1200 mg capsule is $0.20.
Is There any Research?
There are 5770 publications on Carraluma Fimbriata and this includes just 55 clinical trials. To put this into context, there are 130,000 publications on weight loss and over 11,000 clinical trials.
Does Caralluma Fimbriata Provide Antimicrobial Benefits?
A 2014 study carried out in India reported that Caralluma has some antibacterial activity against bacteria including Staphylococcus aureus, Bacillus and E coli (6). The study team used a disc diffusion methodology. This means that bacteria are grown on a plate and discs containing the anti-infective agent are placed on the plate.
The team then measure the zone of inhibition of growth around the anti-infective disc. The more potent the anti-infective agent, the larger the zone of non-growth that will be seen around the disc.
I may be unfair here but I found the details of the methodology a little unclear and was left with some questions about the detail which is never a good thing in research.
A different study found that members of the Apocynaceae family had in vitro activity against drug-resistant and difficult to treat bacteria known as Acinetobacter (7).
Yet another study looked at the effects of Caralluma on fungal and helminthic infections (8). Caralluma was collected from Hyderabad and its antifungal activity against Aspergillus niger and Cladosporium was compared with standard antifungal medication, miconazole nitrate.
The activity of Caralluma against the adult earthworms, Pheretima posthuma, was also evaluated and compared to the standard medication usually used which is called piperazine. The study reports that Caralluma has good activity against selected fungi and worms and is comparable in effect to standard medication.
Again, this was a very brief report of a laboratory-based study which would make it hard to be evangelical about possible anti-infective effects of Caralluma.
There are no human clinical anti-infective studies on Caralluma.
Does Caralluma Fimbriata Protect Kidneys or Protect From Oxidative Stress?
All we have to go on here is a handful of animal studies.
A 2016 study from India was carried out in rats who had been fed a high-fat diet deliberately designed to induce metabolic change and oxidative stress (9). The rats then either had no treatment or treatment with metformin (an anti-diabetic agent) or Caralluma.
The Caralluma protected against renal damage as evidenced by statistically significant and favorable changes in levels of plasma urea, uric acid, creatinine, and renal transaminases.
Furthermore, statistically significant and favorable changes in levels of lipid peroxidation, protein oxidation levels, and glutathione suggested protection from oxidative stress.
Similar results were seen in a 2016 study from India which showed that caralluma could protect against insulin resistance and oxidative stress in rats fed a 60% fat diet (10).
There are numerous other similar studies in animals but none in humans.
There are ho human studies looking at the effects of Caralluma Fimbriata on renal or oxidative status.
Does Caralluma Fimbriata Reduce Blood Sugar Levels?
A study from Tamil Naidu showed that extract of Caralluma had an antihyperglycemic effect in a cell line (11). The higher the concentration of Caralluma, the greater the effect on blood sugar levels in this study. The authors suggested that Caralluma may exert its antihyperglycemic effect via alpha-amylase and alpha-glucosidase.
There are no studies in humans which means we cannot draw any meaningful conclusions here.
Does Caralluma Fimbriata Improve the Digestive System?
There are no real studies looking at Caralluma for digestive health. This is a long shot but here goes. Caralluma is a vegetable and has fiber and therefore assumed to be good for digestive health (12). There are no human studies giving us clinically relevant data on this subject.
This is unproven at this time.
Does Caralluma Fimbriata Prevent Artery Hardening?
A 2016 study looked at the effects of a high-fat diet in mice on atherosclerosis or hardening of the arteries (13).
The mice had either a normal diet or the high-fat cafeteria diet alone or the high-fat cafeteria diet plus caralluma. The high-fat cafeteria diet consisted of condensed milk + bread + peanuts + pellet chow or chocolate + biscuits + dried coconut + pellet chow or cheese + boiled potatoes + beef tallow + pellet chow.
The study took place over 90 days. Feeding rats a cafeteria diet with high-fat content caused deposition of lipids in the aortic arch while treating rats with caralluma completely prevented lipid deposition.
Despite impressive results in mice, there are no data in humans to support a role for Caralluma in the prevention of atherosclerosis.
Does Caralluma Fimbriata Help Build Muscle?
This question is far from definitively answered. A study in diet induced diabetic rats showed that Caralluma could reverse degenerative changes of muscle myofibers associated with fat deposition (14).
Interesting as this might (or might not) be, it tells us nothing about humans and nothing about non-diet induced states.
There is too little evidence to hazard a guess as to whether Caralluma could help build muscle.
Does Caralluma Fimbriata Improve Brain Function?
A group of very unlucky mice were fed d-galactose for seven weeks to impair their brain function (15). They then received Caralluma tuberculata for two weeks. I realize that "tuberculata" is not "fimbriata" but this is the study that we have available to us. The Caralluma significantly reversed the deficits in learning, memory and spontaneous activities in these poor confused mice. Again mice and not humans.
There is no proof that Caralluma can help with brain function in humans.
Does Caralluma Fimbriata Enhance Weight Loss?
Australian investigators from Victoria University carried out a comprehensive review of natural products for the treatment of obesity (16).
They found fourteen relevant studies. They found that Caralluma fimbriata extract and a combination supplement containing Garcinia cambogia plus Gymnema sylvestre were the only treatments that showed positive results.
This Australian research group then followed up their review with a pilot study on Caralluma (17). I have to say that the very fact that reviewers followed up with a clinical study makes me think that the reviewers were pretty impressed with the results of their own review which is a good starting point.
They studied the effects of Caralluma in overweight and obese adults. Study subjects were randomized to either Caralluma 1gm or placebo daily for 12 weeks. All study subjects had advice and weekly follow up regarding exercise and diet during the study period.
The study found that controlling the dietary intake and exercise improved body weight and favorably influenced the metabolic risk profile (I think we already knew that). Did the Caralluma make a difference?
The Caralluma group lost 6.5 cm in their waist circumference compared to 2.6 cm loss in the placebo group. This difference was considered to be significant. Waist to hip ratio also improved significantly after 12 weeks of intervention in the experimental group.
A study from Bangalore compared Caralluma at a dose of l g per day for 60 days to placebo in fifty adult men and women (25-60 years) with a body mass index (BMI) greater than 25 kg/m2 (18). The results are a bit confusing. On the one hand, there was a significant decrease in waist circumference and hunger in the treatment arm of the study.
On the other hand, there was no significant difference in body weight, body mass index, hip circumference, body fat and energy intake. How do we reconcile these findings? The Caralluma arm felt less hungry but ate just as much as the placebo arm? Furthermore, they had no significant change in weight? I think we have to take this as a negative study.
Other researchers from Victoria University looked at Caralluma in Prader Willi Syndrome (19). They randomized 15 children and adolescents with Prader Willi to either Caralluma or placebo for four weeks. This was followed by a two week washout period. They then took either Caralluma or placebo for another four weeks.
This way, every study participant received both Caralluma and placebo. The study showed a statistically significant easing of hyperphagia (overeating) and in hyperphagic behaviors such less clock-watching and asking for breakfast, food, or snacks.
We do not have the type of large scale, long term double-blind placebo-controlled trial that we need in order to decide if Caralluma can help with weight loss but there are some preliminary suggestions that this is a question worth studying.
Is Caralluma Fimbriata Safe?
Caralluma is classified as Generally Regarded As Safe (GRAS) by the FDA (5).
For starters, here is too little research to recommend a specific dosing schedule for Caralluma. We need a dosing range in order to assess safety.
The main side effects of Caralluma are stomach upset and constipation and these symptoms tend to settle with time.
It is best avoided in pregnancy and breastfeeding as there is too little safety information to reassure us that it would be safe for mom and baby.
A 2013 study assessed the safety of Caralluma in a series of laboratory studies (20). They found no evidence of toxicity in cells, rats and pregnant rats.
How I wish that instead of all the speculation about Caralluma, that someone did a really good clinical study that answered the question about whether or not Caralluma is any good for anything. Yet again, we find that there is too little data to draw any conclusions.
In the meantime, I better go for that run and cancel the pizza.