Cat’s Claw (Uncaria tomentosa) is a woody vine found in the tropical jungles of South and Central America.
In fact, there are two species of Cat’s Claw commonly used in North America and Europe, Uncaria tomentosa and Uncaria guianensis, and each has its own properties and uses.
It is Uncaria tomentosa that is more commonly used in traditional medicine, and is the variant known to most American herbalists.
There have been a wide variety of uses ascribed to Cat’s Claw throughout history, but only a handful of them are backed up by anything like sufficient scientific research to be recommended in modern medicine.
Nevertheless, Cat’s Claw has become intensely popular on the back of not just the claims for which there is sufficient evidence, but also the claims of health benefits that remain either wholly or mostly unsubstantiated.
It’s become popular to take Cat’s Claw as a liquid extract, a powder, a tea, and in easy-to-swallow capsule form.
Cat’s Claw: its uses in modern medicine
It’s fair to say that Cat’s Claw doesn’t have prescribed uses in modern medicine. Far more research needs to be done to achieve that level of certainty when it comes to cause, effect, dosage, and administration method.
What modern medicine is prepared to say about Cat’s Claw comes at all times with a heavy caveat that it may do this, and it may do that.
With that understanding, science agrees that Cat’s Claw:
May strengthen the immune system
Two studies, of a small (and therefore not entirely useful) size, support the notion that consuming 700 mg of Cat’s Claw extract per day over the course of two months may promote the growth of white blood cells – the body’s defenders against infection.
One study contained 27 men, and reported that after two months of taking Cat’s Claw at the stated dosage, the white blood cell count of the men had increased.
The second study was even smaller, testing just four men, but importantly, it also found an increased number of white blood cells in its subjects after a six-week period of taking Cat’s Claw.
While it’s not scientifically safe to extrapolate from such small sample sizes, the second study seems to suggest that the effect of Cat’s Claw, if that’s what it is, occurs faster than the two-month period of the first study.
The results seem to indicate that Cat’s Claw may work from both ends against the middle – it may boost your immune response if you need it, and calm an overactive immune system, to regulate the system towards an optimum level.
We would need far larger sample sizes, including subjects across a broad spectrum of society, before we could definitively put ‘increases white blood cell count and boosts immunity’ in the pro column for Cat’s Claw, though.
It’s also notable that no similar research has yet been done with female or non-binary subjects.
May relieve osteoarthritis symptoms
This could be huge in the United States, were it to be scientifically proven, because osteoarthritis is the single most common joint condition in the country.
Osteoarthritis is the most common joint condition in the United States, affecting 10% of Men over 60, and 13% of women in the same age bracket.
Again though, as yet, the scientific evidence supporting the taking of Cat’s Claw to relieve osteoarthritis symptoms is woefully weak, largely due to small test sample sizes.
One study reported that people who all had osteoarthritis in their knee took 100 mg of Cat’s Claw extract over the course of 4 weeks and noted a reduction in their pain levels during physical exercise – with no reports of particular side effects!
Sadly though, the sample size was only 45 people, which is in no way large enough to make it an accepted cause and effect in modern medicine.
It’s also true that the subjects reported no change in either their pain levels when at rest, or in the swelling of their knees, which, while it doesn’t undermine the interest in the results, does narrow the potential focus of their application.
Similar studies run over the course of eight weeks combined Cat’s Claw and Maca Root, and subjects reported both reduced pain and reduced stiffness in people with osteoarthritis.
Subjects also reported needing to resort to pain medication less frequently.
Meanwhile, a third trial combined 100 mg of Cat’s Claw extract with a daily mineral supplement for people suffering from osteoporosis.
Frustratingly, while for the first two weeks, joint pain and joint function improved compared to the control group who weren’t on the regime, by the time eight weeks had elapsed, the perceived benefits had evaporated.
None of these studies conclusively disprove the idea that Cat’s Claw may help with osteoarthritis pain. But sadly, none of them are yet large enough nor conclusive enough to prove that it does help, either.
May relieve rheumatoid arthritis symptoms
Rheumatoid arthritis is another big issue in the US, with more than 1.28 million adults affected by the condition.
Again, they’re significantly less than conclusive, but some studies suggest that Cat’s Claw may help relieve the symptoms of this autoimmune condition.
For example, a study of 40 rheumatoid arthritis sufferers reported that taking 60 mg of Cat’s Claw extract per day alongside their regular medication gave a 29% reduction in the number of painful joints, compared to a group that did not add the Cat’s Claw.
Encouraging, certainly, but too small a sample size to be conclusive.
What is clear is that larger studies with wider, more diverse subjects would be extremely beneficial to those with osteo- and rheumatoid arthritis in the US – if they found a conclusive link between taking a dose of Cat’s Claw and the reduction of inflammation and pain, it could be officially welcomed into the sphere of modern scientific treatments.
If it didn’t, the question could at least be settled once and for at least a generation.
Also unofficially used for…
Despite the things it looks as though Cat’s Claw might have a genuine beneficial effect on, the list of claims for the vine’s root bark include many more for which there is at present little to no evidence.
These include:
- viral infections
- anxiety
- stomach and bowel disorders
- allergies
- high blood pressure
- gout
- asthma
- ovarian cysts
- Cancer
- AIDS
If you’re going to aim high, why not aim all the way? That seems to be the thinking behind the list of claims for Cat’s Claw. At present though, there is a lack of research to back up claims that Cat’s Claw helps with anything from gout to AIDS and cancer.
It is probably fair to say that if Big Pharma believed Cat’s Claw had even a chance of alleviating the symptoms or pain of allergies, high blood pressure, AIDS, or cancer, the test would be in laboratories and trials even now.
Cat’s Claw is also used as a dietary supplement, supposedly able to help with everything from viral infections (such as herpes, human papillomavirus, and HIV), Alzheimer’s disease, cancer, arthritis, diverticulitis, peptic ulcers, colitis, gastritis, hemorrhoids, parasites, and leaky bowel syndrome.
None of this has the necessary level of scientific proof to back up the claims made on behalf of Cat’s Claw.
Side Effects
Ask your doctor before taking Cat’s Claw if you have any auto-immune disease. There is a possibility that it could over-stimulate your immune system, as indicated by the small-scale studies that resulted in white blood cell stimulation.
Likewise, check with your healthcare professional if you have bleeding disorders or high blood pressure. Taking Cat’s Claw may affect your blood chemistry, so it is wise to check ahead.
This also applies if you’re due to go in for surgery any time soon – advise any surgeon or surgical team about your consumption of Cat’s Claw.
This may seem unlikely, but taking Cat’s Claw may also compromise the effectiveness of some of your prescribed medications, as it may affect the functioning of the liver in some cases.
Again, check with your doctor if you’re already on a significant amount of medication before adding Cat’s Claw to the mix.
Cat’s Claw: the history of an herb
Cat’s Claw has been used by the indigenous people of Central and South America for 2,000 years.
Given the relative lack of effective understanding of any health benefits from taking it in modern medicine, we have to wonder… why?
Unlike plants that have had a long history of use in Western medicine, be it mainstream or alternative, the origins and the location of the Cat’s Claw (within the Amazon rainforest, and historically, within the territory of tribes and civilizations like the Inca) make the vine almost entirely enigmatic.
Little has been written on its history, its usage by the people in whose back garden it has grown. In fact, for the most part, when it comes to Cat’s Claw, what we have is less history than legend.
According to what legend we have about its use for 2000 years, most of it unknown by Western medicine, the Inca used the root bark of the Cat’s Claw vine in a number of different preparations, depending on their need on a given day.
It was apparently used to ward off infections when they arose, and also to fight inflammation.
How did it work to fight infections and bring down inflammation?
Ironically, the answer seems to be through the use of toxic chemicals which the vine used to discourage predator insects, animals, fungi, bacteria, and viruses that are almost intensely common in a tropical rainforest.
What’s good for the vine, it turns out, was probably good for the humans too. To get chemical for a second, the root bark contains indole and oxindole alkaloids, as well as polyphenols and terpenoids.
Yes, it sounds like a Star Trek alien convention, but these chemicals are inimical to the likes of viruses and bacteria, and so, it’s thought that by adding the root bark to some preparations, the Inca were able to borrow the protection from the root and use it for their own purposes.
While the chemicals may be hostile to bacteria and viruses, in the human system, claims have been made that they bring a range of positive effects.
Among those effects, they’re said to stimulate the immune system (as has been at least anecdotally indicated by some modern experiments), act as an anti-inflammatory (which has likewise had at least some positive anecdotal evidence to support it in tests with sufferers of osteo- and rheumatoid arthritis), have an analgesic effect, work as a mild anticoagulant, and act as an antihypertensive.
If this sounds like overhype for a wonder drug, it’s worth keeping in mind the small-scale experimental results with immunity boosting and arthritic pain reduction.
It’s also worth keeping in mind that if we believe the Inca used the root bark for 2000 years or thereabouts for these multiple purposes, it’s also worth considering that they were not a stupid people, and if they observed a history of failed results with the root bark… it’s very likely that they would have stopped using it.
There are some unusual side effects though. While most of the indole alkaloids are relatively side-effect-free, tetracyclic oxindole alkaloids can result in gastric bleeding, by virtue of that mild anticoagulant effect.
It would be interesting to know whether the Inca had a history of higher-than-average death rates from gastric and intestinal bleeding. Knowing that, however, seems forever beyond us.
Needless to say, though, the tetracyclic oxindole alkaloids are removed from the Cat’s Claw preparations available for sale today.
One other thing is worth noting. One side effect that is now understood is a mild contraceptive effect of the indole alkaloids.
As such, women who want to get imminently pregnant should probably not add Cat’s Claw to their diet for a while.
It’s unlikely that the Inca understood what we call indole alkaloids. But one of the reasons they may have kept using Cat’s Claw might well have been the understanding of the root bark’s potential contraceptive effect.
While our knowledge of Cat’s Claw’s usage in history is relatively enigmatic compared to many potentially useful herbs and plants, there is a distinct line between what we know of its historical usage and the things with the highest likelihood of being proved useful by modern science.
While along the way, there are claims that Cat’s Claw can be used to treat a whole range of other conditions, we need to do much more scientific research into the root bark before we can validate or dismiss those claims.
