If you’re a parent, you might have noticed toddler “milk” while browsing the formula aisle. The powdered drink, aimed at children between 1 and 3, often pledges benefits like “improved brain development” or “improved immune function.”

But you may not know that these products are largely unregulated and make claims that are not supported by science, according to studies. For this reason, among others, public health authorities around the world have long sought to police such advertising. Yet despite these efforts, toddler milk has grown to become a $20 billion global business.