Adding even a little water to the infant formula - an artificial substitute for human breast milk - can prove fatal for children, a conference has heard.
Water intoxication, especially in babies, can cause sodium in the blood to plummet, causing seizures, brain damage and, in severe cases, death.
Pediatrician James Orlowski told NBC today that few people have any clue that too much water can be dangerous, particularly to tiny tots who cannot typically tolerate extra H2O in their diets until they're at least 10 months old.
"If I had known it was harmful. I never would have done it," Scientific American quoted her as saying.