The centuries-old Jesuit saying, "give me a child until he's 7 and I will show you the man", may be true in more ways than the Jesuits could have imagined. New research into brain development, human biology and behaviour is showing how early experience can affect our health and well-being for the rest of our lives. As Jill Eisen reports, even so-called "life-style" illnesses, like heart disease and diabetes, may have their roots in early childhood.

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