Cat’s Claw Bark
Cat’s claw, also known as “Uncaria tomentosa”, is a tropical vine that can grow up to 98 feet tall. It is found mainly in tropical areas of South and Central America and the Amazon rainforest. Its name is derived from its thorn, which resembles the claw of a cat. The root and the bark of cat’s claw is used for the treatment of a wide array of medical conditions such as inflammatory diseases, cancer, and various infections. Cat’s claw can be consumed in the form of liquid extract, capsule, powder, or tea.
Overall Health Benefits of Cat’s Claw Bark
- Improves symptoms of diabetes [1-3]
- Lowers blood pressure [4-5]
- Speeds up wound healing [6-9]
- Prevents Alzheimer’s disease (ad) and boosts cognitive health [10-16]
- Fights cancer [17-28]
- Treats inflammatory conditions [29-35]
- Fights infection [36-40]
How Cat’s Claw Bark Works
Cat’s claw has antioxidant properties that help the body eliminate cell-damaging particles. Aside from this, cat’s claw is jam-packed with different phytonutrients (plant nutrients) such as alkaloids, glycosides, tannins, flavonoids, and sterols, which are known to exert potent medicinal properties.
Proven Health Benefits of Cat’s Claw Bark
Improves Symptoms of Diabetes
Evidence suggests that cat’s claw has anti-diabetic properties that can benefit people with diabetes mellitus and chronic elevations in blood sugar levels:
- In male mice, administration of cat’s claw extract prevented the progression of immune-mediated diabetes. 
- In obese mice, treatment with cat’s claw extract improved glucose homeostasis and reverted non-alcoholic fatty liver disease. 
- A study found that cat’s claw exerts its anti-diabetic effects through its antioxidant properties. 
Lowers Blood Pressure
Studies also suggest that cat’s claw has antihypertensive properties necessary for the treatment of high blood pressure:
- A study showed that cat’s claw reduced blood pressure in hypertensive patients and relieved various neurological symptoms. 
- A study found that hirsutine, a substance extracted from cat’s claw, produced blood pressure-lowering effects. 
Speeds up Wound Healing
Numerous studies also show that cat’s claw can help accelerate the wound healing process:
- A study found that cat’s claw can speed up the wound healing process through its anti-inflammatory and antimicrobial properties. [6-8]
- A study found that cat’s claw produced antimicrobial effect against various human oral pathogens such as Enterobacteriaceae isolates, Streptococcus mutans, and Staphylococcus aureus. 
Prevents Alzheimer’s disease (AD) and Boosts Cognitive Health
There’s also a good deal of evidence supporting the benefits of cat’s claw on cognitive dysfunction associated with AD and old age:
- A study found that the proanthocyanidin constituents of cat’s claw can inhibit the formation of brain plaques and tangles (primary cause of AD). 
- In mice with experimental amnesia, the alkaloid components of cat’s claw improved memory function. 
- A study found that PTI-00703, a proprietary extract of cat’s claw, inhibited the formation of beta amyloid fibrils (contributes to AD) and dissolved pre-formed amyloid fibrils. 
- A study also reported that cat’s claw can potentially improve learning and memory by increasing the levels of the brain-derived neurotrophic factor (BDNF). 
- In normal individuals aged 18–35 years old, administration of a dietary supplement containing 25% cat’s claw bark powder for 6 weeks improved short-term memory and executive function. 
- In patients with dementia, administration of a dietary supplement that contains 20% cat’s claw bark powder improved cognitive function and activities of daily living. 
- In healthy adults, administration of 250 and 350 mg/day tablets containing an aqueous extract of cat’s claw protected against DNA damage, suggesting that the treatment can help reduce the risk of brain disorders. 
Several lines of evidence show that cat’s claw has anti-cancer properties and can help reduce the side effects of chemotherapy:
- In patients undergoing chemotherapy, the addition of cat’s claw extract reduced the adverse effects of the treatment. [17-20]
- A test tube study found that the bark of cat’s claw inhibited the growth of human breast cancer cell line MCF7. 
- In human leukemia cells, cat’s claw prevented the multiplication of cancer cells by inducing programmed cell death (apoptosis). 
- In patients with advanced cancer, treatment with cat’s claw improved quality of life and reduced fatigue. 
- A study also found that cat’s claw could be useful in enhancing the death of cancer cells after anti-cancer therapies. 
- A cell study found that cat’s claw can enhance the toxic effects of chemotherapeutic drugs on cancer cells. 
- In rat breast cancer cells, cat’s claw exerted its anti-cancer effects by modulating oxidative stress. 
- In mouse lung cancer cells, cat’s claw significantly inhibited tumor growth by inducing cell cycle arrest. 
- In colon cancer cells, cat’s claw enhanced chemotherapy-induced apoptosis. 
Treats Inflammatory Conditions
Several studies also support the potent anti-inflammatory effects of cat’s claw:
- In patients with osteoarthritis, treatment with cat’s claw extract improved joint health and function after 1–2 weeks. [29-30]
- In patients with rheumatoid arthritis, 24 weeks of treatment with cat’s claw extract significantly reduced joint pain. 
- In mice with respiratory inflammation, cat’s claw protected against ozone-induced lung inflammation. 
- In an animal model of inflammation, cat’s claw produced anti-inflammatory effects similar to dexamethasone. 
- In rats with arthritis, cat’s claw treatment reduced joint pain and inflammation. 
- In rats with chronic intestinal inflammation, oral administration of cat’s claw reduced the levels of inflammatory substances. 
Numerous high-quality studies suggest that the immune-boosting properties of cat’s claw can help ward off a wide array of infections:
- A study found that the presence of polyphenols in cat’s claw bark can help treat herpes infection. 
- In HIV-positive individuals, supplementation with cat’s claw increased the numbers of white blood cells. 
- A study reported that individuals supplemented with a novel water soluble extract of cat’s claw exhibited significant immune enhancement which protected against pneumonia. 
- In human white blood cell samples infected with dengue virus-2, cat’s claw produced antiviral effects which significantly reduced infection rates. 
- A cells study also found that cat’s claw can improve the antifungal effects of fluconazole. 
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- Hirsutine extracted from cat’s claw was reported to Ccahuana-Vasquez RA, Santos SS, Koga-Ito CY, Jorge AO. 2007. Antimicrobial activity of Uncaria tomentosa against oral human pathogens. Braz Oral Res. 21:46–50.
- Snow AD, Castillo GM, Nguyen BP, et al. The Amazon rain forest plant Uncaria tomentosa (cat’s claw) and its specific proanthocyanidin constituents are potent inhibitors and reducers of both brain plaques and tangles. Sci Rep. 2019;9(1):561. Published 2019 Feb 6. doi:10.1038/s41598-019-38645-0.
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