Today—March 9—is Vitamin D Day—according to the Milk Mustache “Got Milk” Campaign. They are reminding Americans that many don’t get enough vitamin D and that shortages are linked to risk for a variety of diseases.

It’s true. There is a growing body of research showing that vitamin D helps to protect against bone loss and a host of other ailments, perhaps including cancer and depression. But the industry’s spokesperson, a registered dietitian, isn’t quite telling the whole story when she says that foods, not supplements, are the best source of vitamin D.

Whether or not that statement is true, it has nothing to do with milk and vitamin D. Milk and other dairy foods are not naturally rich in this nutrient. They are good sources only because they are fortified with vitamin D. So getting your vitamin D from milk is really not any different from getting it from a supplement. And it’s no different from getting it from fortified cereal or fortified soymilk. Although many brands of soymilk are fortified with a plant-derived source of vitamin D, research shows that it is just as effective as animal-derived vitamin D in keeping us healthy.

Although some people can get adequate vitamin D from sun exposure, most of us can’t. And it is wise to limit direct exposure to sunshine to minimize skin cancer risk, too. So looking to the diet to meet vitamin D needs is a good idea. But the idea that cow’s milk is the best or most natural way to get vitamin D is just wrong.