What is African birch?

African birch is a tall savanna tree of West and Central Africa. Its botanical name is Anogeissus leiocarpus. In Hausa it is known as marke.

The bark, leaves and roots are the parts most used. Healers boiled them in water, dried them to a powder, or made washes for the skin. The twigs were also chewed as tooth sticks.

Here is the plain evidence verdict. Nearly all testing has been done in test tubes and in animals. Good human trials are missing, so long traditional use here is not proof that it works, and not proof that it is safe.

How does African birch work?

No one has shown in people how African birch works, or that it works at all.

The bark is very rich in tannins. In test tubes, tannins bind to proteins and tighten tissue. That is the likely reason bark washes feel drying on a weeping sore.

In laboratory tests, bark extracts slow the growth of some bacteria and fungi. Lab work also shows activity against the parasites behind sleeping sickness and malaria. Whether any of that happens inside a human body is not known.

In rodents, extracts have lowered blood sugar and calmed gut spasm in some studies. Animal results often fail to repeat in people. Treat them as leads, not as findings.

What forms does African birch come in?

African birch is mostly sold as raw plant material, not as a finished product.

Common forms include: - Dried bark pieces, boiled in water as a decoction - Bark or leaf powder - Washes and soaks for the skin - Twigs sold as chewing sticks for the teeth - Trunk gum, and bark used as a yellow dye for cloth and leather

Capsules and tinctures are rare outside Africa. Market bark is often unlabelled, so you cannot tell the species, age or purity by sight. Mix-ups with other Anogeissus trees are reported.

Where it comes from:

African birch has long standing in West African plant medicine, from Senegal across to Nigeria and Sudan.

Traditional healers used bark decoctions for diarrhoea, fevers and worms. Bark and leaf washes were applied to wounds, boils and skin sores. Twigs were chewed to clean teeth and firm the gums.

The tree also served daily life outside medicine. Its bark gave a yellow dye for cloth and leather, and its wood was burned as fuel. These records describe what people did in the past; they are not a reason to treat yourself with it now.

What does African birch help with?

• Diarrhoea: Bark decoctions were a common village remedy for loose stools. Tannins tighten tissue in test tubes, which is the usual reason given. No human trial has tested African birch for diarrhoea.
• Wounds, boils and skin sores: Washes and powders were put on sores to dry and close them. Lab tests show bark extracts slow some wound bacteria. Whether that helps real skin is untested, and a deep or spreading wound needs medical care.
• Mouth and gum care: Marke twigs were widely used as chewing sticks. Lab work shows activity against some mouth bacteria. There is no trial showing less decay or less gum disease in people who use them.
• Fever and malaria: Bark and leaf drinks were given for fever in malaria country. Extracts kill malaria parasites in the test tube and in some rodent work. That is not evidence it treats malaria in people, and malaria can kill without proper drugs.
• Worms and other parasites: Healers used the bark against worms and sleeping sickness. Laboratory results against trypanosomes are among the most studied findings for this tree. Human studies are absent.
• Coughs and sore throat: Decoctions and gargles were used for throat trouble. The drying, astringent taste may explain why a gargle feels soothing. No trial has measured any effect on cough.

What are the side effects of African birch?

• Nausea and stomach upset
• Constipation
• Dry, puckering feeling in the mouth
• Gum or mouth irritation from chewing sticks
• Poorer iron uptake from food, with heavy use
• Skin rash where a wash is applied
• Liver or kidney strain with large, long-term use (seen in animals)

Good to know:

Side effects are not well counted, because no one has run a proper safety study in people.

The common complaints are gut-related. They come from the heavy tannin load. They usually settle when you stop.

The serious worry is the liver and kidney damage seen in animals given large doses for long periods. Stop and seek care if you feel unwell.

How much African birch should you take?

• Recommended daily: No safe or tested amount has been set for African birch, so this page gives none. Raw bark in a market carries no label. The few packaged powders that exist do not agree with each other. Because no human study has tested any amount, any number here would be a guess dressed up as advice.
• Best time of day: Time of day has not been studied and is unlikely to matter. Nothing in the plant is known to act on sleep or body clock.
• With or without food: Tannins taste harsh and can upset an empty stomach. Food may ease that, but food also binds tannins and may blunt any effect. Keep any bark drink well away from iron tablets and from other medicines you swallow.
• Time to effect: There is no honest answer, because no human trial has measured one. It may do nothing at all. If you are treating an infection, fever or wound and nothing improves within a day or two, get medical care.
• How long to take it: No safe length of use is known. Traditional use was short and for a specific problem, not daily for months. Long, heavy intake of high-tannin bark has harmed the liver and kidneys in animals, so open-ended use is a poor idea.