Milk can provide a large portion of the calories needed for children.
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Young children who retain the ability to digest milk benefit from the large increase in available calories, and this may explain why the mutation spread rapidly in some human populations several thousand years ago.
These extra calories greatly increase children’s chances of surviving an infection, because malnourished children are more likely to die if they become seriously ill, says Alexandre Fabre, a pediatrician at the Timon Infante Hospital in Marseille, France. who led the study.
milk is…