From Early Ed Watch:
Why such significant differences? The researchers lay out several potential reasons: The effects of poverty on brain development are linked to cognitive ability in later years. Poverty can affect a family by elevating the stress parents feel and causing an increased likelihood of harsh parenting practices. These practices have the greatest impact during the early childhood years when the mother-child relationship serves as the foundation for a child's ability to regulate his emotions. That regulation, in turn, has an effect on children's achievement, behavior, and health. With little money to spare beyond day-to-day living expenses, parents can’t afford to financially support emergent literacy with books, educational toys and activities. These experiences in the early years are the basis of prior knowledge necessary for later school success.
Poverty can even touch children in the womb, with pregnant mothers' low incomes leading them to purchase less nutritious food , which leads to babies born at lower birth weights. That same lack of nutrition can lead to unhealthy weight gain as children grow. The pattern of low birth weight followed by rapid weight gain can lead to insulin resistance, the primary characteristic of diabetes, according to researchers into childhood links to adult disease.
The study provides some of the strongest evidence yet of the link between early childhood poverty and long-term adult outcomes. A proactive birth to five public policy, targeting the well being of our youngest citizens, would go a long way toward better outcomes for all of society.