Plant-based milks are great, but they’re not milk. While humans don’t require cows milk to be healthy, cow’s milk is nutritionally supercharged; its whole job is to deliver nutrition to infants before they can consume anything else. As adults, most of us can find those nutrients elsewhere, so what goes in your cereal probably won’t leave you malnourished. However, for some people swapping to a plant milk might leave them lacking. Take iodine, for example: recent studies found pregnant women in the UK are iodine deficient, and iodine is critical for fetal growth and development. While one study found plant milks have around three micrograms of iodine per cup, dairy milk has 85, making it way more in line with nutritional recommendations during pregnancy. Additionally, while some plant milks might compare in the protein department, cow’s milk provides critical micronutrients like calcium, zinc, and B vitamins to growing infants and toddlers with more limited diets. Therefore, choosing what milk goes in a sippy cup is more important than what goes in the latte.