African black soap

What it is

African black soap is a traditional West African soap, ose dudu in Yoruba and alata samina in Ghana. Plantain skins, cocoa pods and other plant waste are burned, the ash is soaked to draw out its alkali, and that lye is cooked with palm oil, palm kernel oil or shea butter into a soft, crumbly, brown-to-black mass^{1, 2}. Recipes vary by region and family¹. As a true soap it is alkaline, typically around pH 9 to 10, while healthy skin sits near pH 4.7^{3, 4}.

What the evidence says

Evidence: limited. One survey of 100 users reports high satisfaction but measured no skin outcomes; antibacterial activity has been shown only in the laboratory.

In the one published survey, 100 New York users most often used it for general skin care (70%), acne (23%) and dark spots (20%), and 91% were satisfied, but nobody's skin was examined and side effects were not assessed¹. Laboratory tests show its extracts stop the growth of bacteria such as Staphylococcus aureus, as most soaps do^{2, 5}; no study has tested whether that changes acne. There are no trials for dark spots, and scrubbing marks with an irritating soap can worsen post-inflammatory hyperpigmentation. Our guide to African black soap and shea butter covers the research and a safe routine.

How people use it

• As a body wash, where its strength is an advantage against sweat and odour, followed by moisturiser.
• On oily facial skin as an evening cleanser, once a day at most; many do better with two or three evenings a week (see oily skin and clogged pores).
• Lathered in wet hands and applied as foam for twenty to thirty seconds, then rinsed well; never rubbed on as a bar or left as a mask.
• Stored dry, since the soft bar turns to mush.

Cautions

• It dries and irritates. Alkaline soap raises skin pH for hours and strips barrier lipids, causing tightness, flaking and stinging^{3, 4}. Moisturise after every use and stop if your skin feels tight.
• Not for eczema-prone, very dry, sensitive or broken skin. In eczema, washing with alkaline soap depletes protective lipids⁴; wash with an emollient instead (see eczema and dry, itchy skin).
• Dark marks. On brown and Black skin, irritation can trigger or deepen post-inflammatory hyperpigmentation; see dark spots and hyperpigmentation.
• Keep it out of the eyes, patch test first, and treat dyed, perfumed "black soap" bars as a different product. If stinging does not settle after stopping, see when to see a dermatologist.