All varieties of Cool Whip have long contained sodium caseinate*, or milk protein, making them off limits for those who are allergic to casein or who choose to live dairy-free. However, several varieties, including the Original Cool Whip, were lactose-free, and used by many people who are lactose intolerant.

Unfortunately for those individuals, Kraft Foods has announced an ingredient change for the Original version of Cool Whip, "Kraft Foods would like you to know that it recently changed the recipe for the Original variety of Cool Whip whipped topping so that it now contains additional milk ingredients, including cream." This means that the new version will contain some lactose. A better option may be TruWhip, which still appears to be lactose-free (and has a better ingredient list overall), but does contain casein. Be sure to read the labels to ensure a product is safe for you.

* Products with a very small amount of caseinate may be labeled as non-dairy, but they aren't actually dairy-free. See the following post for a full explanation: Does My Non-Dairy Food Have Dairy in It?