Terminalia Arjuna, commonly known as just “arjuna”, is a type of tree bark.
This bark is highly integrated within Indian medicine, where they take extracts from the bark and use it for therapeutic purposes.
In most cases it is used for improving cardiovascular health, especially in people that are at serious risk of a cardiac event. Despite its use, the reasoning for protection on cardiac tissue is relatively unknown.
It is usually the water extract of this tree bark that appears to most commonly used in these scenarios, although many different forms of arjuna supplements are now on the market.
Terminalia Arjuna Health Benefits
May Be a Cardioprotective Agent
In fact, the actual term used is a “cardiotonic” supplement, which means it is a substance that appears to have a favorable effect upon the action of the heart.
This classification is based on very limited human research that found 1 month of arjuna supplementation can improve diastolic heart function in people with heart conditions .
Animal studies on arjuna also show promise, with a dose-dependent reduction in fasted blood glucose levels by ~90% . Despite this not seeming relevant to cardiovascular health, blood glucose levels and insulin resistance are very closely associated with cardiovascular risk factors .
These beneficial effects are speculated to be initiated by the antioxidative properties that have been highlighted in various lab studies on arjuna. Surprisingly, these studies even indicate that arjuna is a more potent antioxidant than Vitamin C, however this has not been confirmed in animal or human research . In our opinion, based on the mechanistic functions of both compounds, it is unlikely to ever fully present itself as a viable alternative option to vitamin C and should not be looked at as such.
May Have Anti-Cancer Properties
Experts have stated that arjuna has many different bioactive compounds, such as ethanolic or acetone extracts that could be cancer-protective.
Given, limited research does suggest extracts from the bark exert antigenotoxic (protective) properties, with the proposed bioactive elements appearing to be concentrated in the acetone and methanolic extracts  .
Small amounts of evidence are also available to indicate that arjuna reduces tumor growth and DNA damage in animal models, stemming from the isolated arjunolic acid content. In animals with carcinogenic tumors, just 9 days of consuming the an extract of arjuna was able to reduce tumor size and survival time by ~50% .
Lab studies show even more extreme results, finding that arjunic acid induces up to 70% cytotoxicity in certain cancer cells .
Studies are currently being conducted to isolate and pinpoint the nature of the antimutagenic factor in acetone and methanol fractions.
The current scientific consensus is that although ethanolic extracts demonstrate potential anticancer effects, the recommended dosages for this to be seen are so high that they may lead to harmful side effects due to the cytotoxicity – the quality of being toxic to cells.
How to Take Terminalia Arjuna?
If you would like to take this for cardiovascular health, based on the common doses used in Indian medicine, a sensible amount is ~500mg of the water extract per day. This should be ideally taken in the morning without food.
If you are already suffering with serious cardiovascular problems, this dose can be taken twice per day – one in the morning and another in the evening.
No recommended dose has yet been found for cancer prevention.
Terminalia Arjuna Safety And Side Effects
Although arjuna has a proven safety record in Indian medicine, its safety has not yet been fully determined by substantial evidence.
In animal models, the safety of arjuna is partly dependent on the type of extract in question. Toxicity does not seem to be a problem at intakes up to 2000mg per kg of bodyweight of the ethanolic extract , however the median lethal dose of the leaf extract is noted to occur at 900mg per kg of bodyweight .
There are no indications to just this translates to human practices, although far lower doses such as the ones mentioned above in Indian medicine do not appear to cause any negative side effects.
It is again advised to stick to the water extracts as these are more well-research and determined to be safe at the recommended doses.
Terminalia Arjuna, commonly known as just “arjuna”, is a tree bark that is integrated within Indian Medicine and is linked towards improving cardiovascular health.
Limited evidence suggests its antioxidative capacity has some effect on improving blood pressure and blood glucose levels, although this needs to be proven in human research.
The arjunic acid content may also be a potential anti-carcinogenic agent.
However, no data has yet concluded whether this tree bark is safe to consume, and therefore it cannot be recommended for use. If people are going to consume it, stick to water extracts of arjuna such as in tinctures.