Shea nuts are tree nuts, obtained from the shea tree, which grows in various parts of Africa.
The shea nut is found within the fruit of the tree, and it is oil rich. Widely eaten in Africa, in the West it is generally only consumed in the form of shea butter, which is used in confectionary as a replacement for cocoa butter. It’s also used extensively in cosmetics as a skin conditioner and emollient.
Those allergic to other tree nuts may be apprehensive about consuming shea-containing products.
According to all the evidence … they needn’t be.
The shea nut is treated in various ways to produce refined shea nut butter — cold-pressing, bleaching, deodorising — and the final product is almost entirely fat.
Research has found that shea nut butter contains no IgE-binding proteins, which would suggest any theoretical allergic reaction to it implausible. In that study from 2011, Dr Chawla and her colleagues actually extracted the minimal protein from shea butter samples and tested it on the blood of those with known tree nut allergies, there was barely any binding at all, implying immune systems were not recognising them as nut proteins. No other studies appear to be available, and confirmed reports of allergy to shea nut are unknown.
Shea in Food
In the US, shea nut is considered a tree nut and is a declarable food allergen, so will always be explicitly named on food labels when present. (For more on allergen labelling in the US, see this previous article.)
In the UK, shea nut is not considered one of the eight nuts in the ‘tree nut’ group according to EU legislation, and is therefore not a ‘top 14’ allergen. It will be named in lists of ingredients, but not emphasised.
Shea in Cosmetics
A very interesting opinion statement (PDF file) from the Food Allergy Research and Resource Program (FARRP), at the University of Nebraska, and published in 2018, discusses a collaboration between FARRP and Procter & Gamble to assess the allergenicity of shea nut butter. Their research was unable to detect any cross-contamination of (non-shea) nut proteins or peanut protein in shea nut butter, and using amino-acid analysis and mass spectroscopy techniques, the team could not detect any shea protein in the refined butters tested either.
Their conclusion? That refined shea nut butter is safe for all to use.
But what about unrefined?
This does not undergo whitening or deodorising treatment, is also sometimes used, albeit only in cosmetics.
Unrefined shea butter is likely to contain more proteins than refined, but there is still no evidence that these might be allergenic, nor are there any confirmed reactions to it in the medical literature.
If you wish to play ultra-safe, buy only refined shea butter cosmetics, or check with manufacturers of any products using shea butter in their cosmetics whether they use refined or unrefined. Shea nut butter usually appears as butyrospermum parkii in cosmetics, though the Latin name for shea nut tree is now officially vitellaria paradoxa.
In summary …
It would be foolish to entirely rule out the possibility of a shea nut allergy in an extremely small number of individuals, but it seems that if you have been consuming shea nut butter products without problem, the available evidence and expert opinion suggests you are perfectly safe to continue to do so, and if you been recently diagnosed, there is no research to suggest you need to avoid them.
The American Shea Butter Institute’s FAQ.