If you do a search for “shea butter” here on DailyBeauty, you get five pages of results-more than almost any other skincare ingredient you could search for. That’s because so many companies rely on the nut-derived emollient to make their products more moisturizing. Surprisingly, however, shea butter has gone through very little testing to prove its power.
Swedish researchers recently put any debate to rest by testing shea butter on skin that had experienced trans-epidermal water loss, much like what occurs after showering strips the skin of lipids. They found that shea butter caused rapid recovery and improved barrier properties. In fact, even in deeper layers of the skin, shea butter improved moisture levels at a more consistent and higher rate than mineral oil.
The researchers say they chose to test shea butter because that there’s more pressure in the beauty industry to prove the efficacy of non-active ingredients, giving manufacturers less freedom to make unproven claims.