Yes! There is such thing as too much of a good thing when it comes to milk ingestion.
Most toddlers love milk, but occasionally that milk consumption becomes the primary source of nutrition in a child’s diet. This might be because the child is a picky eater otherwise or because they simply prefer milk’s on-the-go convenience. Milk is also very filling, so a child drinking many ounces of milk each day might not be hungry for much else.
Milk is a poor source of iron and can interfere with iron absorption of other foods when given in excess. This can lead to a slow progression of iron deficiency anemia. Studies have shown that iron deficiency anemia can have a negative effect on neurocognitive development (i.e. loss of IQ points). According to the American Academy of Pediatrics, iron deficiency anemia is most common in 2- to 5-year-olds. If your toddler prefers milk to the exclusion of anything else, tell your pediatrician. A simple test can identify iron deficiency, and treatment simply entails supplemental iron, as well as a change in diet.