Durham, N.C. — A long-term study has found that children who scored lower on measures of self-control as young as age 3 were more likely to have health problems, substance dependence, financial troubles and a criminal record by the time they reached age 32.
Self-control in the more than 1,000 New Zealand children who participated in the study was assessed by teachers, parents, observers and the children themselves. It included measures like “low frustration tolerance, lacks persistence in reaching goals, difficulty sticking with a task, over-active, acts before thinking, has difficulty waiting turn, restless, not conscientious.”
Fast-forward to adulthood, and the kids scoring lowest on those measures scored highest for things like breathing problems, gum disease, sexually transmitted disease, inflammation, overweight, and high cholesterol and blood pressure, according to an international research team led by Duke University psychologists Terrie Moffitt and Avshalom Caspi.
The impulsivity and relative inability to think about the long-term of the lower self-control individuals gave them more difficulty with finances, like savings, home ownership and credit card debt. They also were more likely to be single parents, have a criminal conviction record, and be dependent on alcohol, tobacco, cannabis and harder drugs.
"These adult outcomes were predictable across the entire spectrum of self-control scores, from low to high," Moffitt said.
Yet study participants who somehow found a way to improve their self-control as they aged fared better in adulthood than their childhood scores would have predicted. Self-control is something that can be taught, the researchers say, and doing so could save taxpayers a pile of money on health care, criminal justice and substance abuse problems down the road.
To further corroborate the importance of self-control, Caspi and Moffitt ran the same analysis on a sample of 500 pairs of fraternal twins in Britain and found that the sibling with lower self-control scores at age 5 was more likely than their sibling to begin smoking, perform poorly in school and engage in antisocial behaviors at age 12. "This shows that self-control is important by itself, apart from all other factors that siblings share, such as their parents and home life," Caspi said.
The New Zealand children with low-self control were more likely to make poor choices as adolescents, including taking up smoking, having unplanned pregnancies and dropping out of school. Naturally, this set them on a more difficult path. Even the low self-control individuals who finished high school as non-smokers without kids showed poorer outcomes at age 32.
And because of a greater likelihood of single-parent status and limited income, it's also apparent that "one generation's low self-control puts the next generation at a disadvantage as well," Moffitt said.
"The good news is that self-control can change. People can change," said Alexis Piquero, a professor of criminology at Florida State University who was not involved in the research.
Piquero, who studies the developmental roots of criminal behavior, said there are many time-tested approaches that give parents and teachers the tools to teach self-control. The successful programs practice decision-making, role-playing and learning the consequences of actions.
"Identifying low self-control as early as possible and doing prevention and intervention is so much cheaper" than dealing with prisons, drug programs and personal economic failures, Piquero said. "If you're just making a dollars-and-cents decision, it's a no-brainer."
The study, which appears this week in the Proceedings of the National Academy of the Sciences, was supported by the U.S. National Institutes of Health, the UK Medical Research Council, New Zealand Health Research Council, Hebrew University, and the Jacobs Foundation. Co-authors on the work include researchers from King's College London and the University of Otago in Dunedin, New Zealand.