system
Given the following post, respond as if you're commenting on Reddit:
human
Babies survive by eating solely a mother's milk. At what point do humans need to switch from only a mother's milk, and why? Or could an adult human theoretically survive on only a mother's milk of they had enough supply?
gpt
Babies are born with a store of iron which is sufficient to last about 6 months, but breast milk does not contain sufficient iron to keep a person healthy indefinitely. Even if one had enough breast milk to meet their caloric needs, iron deficiency would be a problem eventually.