Most people are convinced about the importance of early intervention. It just stands to reason that you have more leverage early on, when a child is most impressionable and before negative life experiences take their toll.

And research continues to back up the benefits of acting early, witness a string of presentations at a conference in Chicago – all about life… from beginning to end… and from end to beginning.

Andrea Danese, from the University of London, for example, spoke of his research on the effects of childhood maltreatment. He looked at data collected over 32 years on 1,000 individuals born in Dunedin, New Zealand. Evidence from this and other studies suggests that experiencing abuse or neglect and depression as a child can impair the body’s production of cortisol, an important hormone that reduces inflammation.

Individuals who experience such traumas in childhood are much more likely to have cardiovascular disease, Type II diabetes and other health problems related to inflammation. The implication is that public health campaigns focused on reducing heart attacks, for example, should not only focus on improving the diets and lifestyles of adults but also the safety and well-being of children.

Similar messages on how early experiences alter physiology came out of a presentation by Alicia Mendez, of the University of Chicago, who described her research on obesity among women in poor countries. Through a study in South Africa she found that women who were nutritionally deprived as children were more likely to be obese as adults than women who had adequate diets in childhood. Mendez speculates that poor nutrition early on might affect appetite control later.

Rather than looking at how early experiences might influence later health, two other presenters considered the reverse: how poor health in childhood can set a course towards poor attainment outcomes in adulthood.

Mark Stabile of the University of Toronto considered a large sample of children in the US and Canada and found that children with mental health conditions, particularly Attention Deficit Hyperactivity Disorder were more likely than other children to do poorly in school.

Similarly, Margot Jackson of Princeton University found that children with health problems who participated in large national studies in the US and the UK were more likely to struggle in school and to be placed in less rigorous educational tracks than their healthier counterparts.

One possible explanation for Stabile and Jackson’s findings is that poverty caused both the poor health early on and the poor school performance later. However, the researchers found that even children from well-off families seemed to be knocked off course by early health problems.

Plenty of questions remain about early intervention – the least of which, just how early is early? In other words, to prevent poor outcomes later in life, when does a child need the most help? And what type of help is best? What does seem clear is that the effects of early trauma are long-lasting and not easily healed.

• The Chicago conference Health and Attainment over the Life Course: Reciprocal Influences from Before Birth to Old Age was sponsored by the University of Chicago and Northwestern University.