Just like trends, a beauty ingredient can suddenly become a fad. The latest is apple stem cells, specifically those from the Swiss Uttwiler Spatlauber apple, which is known for staying fresh longer than other apples. In products including 3Lab Super h Serum and Clark's Botanicals Cellular Lifting Cream, the cells slow down aging, according to the companies. Experts are intrigued but cautious. Currently the only study on the cells was conducted by Mibelle Biochemestry, the ingredient manufacturer for these companies. The study results showed that the apple cells can protect the longevity and activity of existing skin cells, and possibly stimulate new skin cells, all of which makes the skin look younger.