When shopping for cosmetics or skin care products, you'll frequently see labels that say the products are "hypoallergenic." That means they are less likely than other cosmetics to cause allergic reactions. It also suggests that these products will be gentler or even safer for the skin.
However, there are no federal regulations that govern the use of the term "hypoallergenic." So it's entirely up to the manufacturer whether or not to label a product this way. And no proof that a product labeled this way causes fewer allergic reactions is needed.
When labeling cosmetics "hypoallergenic" first became popular, the FDA tried to regulate the use of the term. In 1975, the FDA issued a regulation stating that a cosmetic could be labeled "hypoallergenic" only if scientific studies on human subjects showed that it caused a significantly lower rate of adverse skin reactions than similar products not making the claim. The manufacturers were to be responsible for carrying out the required tests. But this rule was declared invalid by U.S. courts, leaving manufacturers free to apply the term as they wish.
The FDA Office of Cosmetics and Colors Fact Sheet notes that ingredients used to make cosmetic products are basically the same throughout the industry. Decades ago, harsh ingredients were sometimes used, and they did sometimes cause adverse reactions for some people. But these ingredients are no longer used. Still, though, there is a lack of studies that show certain products or classes of products cause fewer adverse reactions.
The bottom line is that the term "hypoallergenic" has very little meaning and is primarily used as a marketing tool. It is impossible to guarantee that a cosmetic or skin care product will never produce an allergic reaction. Since the FDA does require cosmetic ingredients be listed on product labels, consumers who have had allergic reactions or problems with a specific substance can avoid purchasing products that contain it by reading the labels.