“After numerous studies, no conclusive findings have been made to suggest a relationship between coffee consumption and impaired growth,” says Kristen Scheney, a nutrition expert with CCS Medical. “The basis of this myth stems from the idea that caffeine in coffee can be the cause of osteoporosis, a vitamin D deficiency that makes the bones fragile.”
She emphasizes that findings show that even in the event that caffeine does have some effect, it would be relatively insignificant and could be stymied by maintaining regular calcium consumption. That’s not to say kids should start downing the stuff (the caffeine would still have them bouncing off the walls). But it’s not going to stunt their growth.