Weaker bones are now a primary indication in kids having an allergy to cow's milk as debunked by a study from the University of Montreal. The study spearheaded by co-researcher Genevieve Mailhot at the CHU Sainte-Justine Research Center listed that in their registry of 52 children with an allergy to cow's milk, 6% of the demographic recorded a low bone density, according to Web MD.