What is tongkat ali? Facts, research and safety

What is tongkat ali?

Tongkat ali (Eurycoma longifolia Jack) is a small tree that grows in the forests of Southeast Asia, including Malaysia, Indonesia, Thailand and Vietnam. The part usually used is the root, known for its very bitter taste. In Indonesia it is also called pasak bumi.

The root contains several groups of compounds that researchers study, mainly quassinoids (such as eurycomanone), alkaloids and glycosaponins.

Traditional use

Traditionally, tongkat ali root decoctions have been used in Southeast Asian folk medicine for various purposes, including fever, malaria, body aches and as a general tonic. These uses are recorded in scientific reviews, but traditional use is not proof that a herb works or is safe for everyone.

Some activities linked to tongkat ali, such as activity against malaria parasites, have only been shown in laboratory tests — not in treating patients.

What do human studies show?

Most clinical research on tongkat ali has focused on the hormone testosterone. A 2022 systematic review and meta-analysis pooled five randomised clinical trials and found that total testosterone levels rose in men taking tongkat ali extract, with the clearest effect in men whose levels were low.

However, the authors themselves highlighted several limitations: small numbers of participants, large differences between studies, possible publication bias, and most studies used the same commercial extract. They concluded that more research is needed before it can be used in clinical practice.

In other words, the evidence so far is limited and should not be read as a guaranteed effect for any individual.

Safety points

In published clinical trials, reported side effects were mostly mild, such as stomach upset and itching. However, in 2021 the European Food Safety Authority (EFSA) assessed a tongkat ali root extract proposed as a novel food and concluded that its safety had not been established, because laboratory and animal tests indicated potential DNA damage at high doses.

The EFSA assessment also excluded pregnant and breastfeeding women. How tongkat ali interacts with other medicines has not been well studied.

• Speak to a doctor or pharmacist first if you have heart disease, blood pressure problems, diabetes, liver or kidney problems, or take any medication.
• Follow the dose on the label and do not combine several products that contain the same herb.
• Stop using it and seek medical advice if you notice any unwanted effects.

Choose registered products

The MOH has found products labelled as traditional or herbal that were adulterated with prescription medicines such as sildenafil and tadalafil — substances that can be dangerous without a doctor's supervision. Before buying any herbal product, check its MAL number and security hologram. Our guide on checking KKM registration explains how, step by step.

Summary

Tongkat ali is a traditional Southeast Asian herb that is being studied scientifically. Early human studies interest researchers, but the evidence is still limited and safety questions remain open. This article does not refer to any product sold on this site.