In one experiment on delayed gratification, four-year-olds were told they could eat some candy now, or more later. Those who couldn't wait were more likely to be overweight as 11-year-olds. (Dan Goodman/Associated Press)

Young children who have trouble delaying gratification in exchange for a larger award seem more likely to gain extra weight before becoming teenagers, a study suggests.

The April issue of the Archives of Pediatrics & Adolescent Medicine includes several studies on childhood obesity. The excess weight tends to last into adulthood, increasing the risk of developing cardiovascular disease, Type 2 diabetes and certain cancers later in life, researchers said.

'In essence, it appears that children with greater self-regulation tend to be leaner, smarter, and better able to get along with others.'— Dr. Robert Whitaker and Rachel Gooze

In one study, Lori Frances and Elizabeth Susman of Pennsylvania State University, State College, assessed how well 1,061 children were able to delay gratification or self-regulate their behaviour.

"The findings reported herein have potential for early prevention of obesity," the researchers concluded.

Encouraging self-regulation and delay of gratification are important for regulating energy intake, they said.

In the experiment, the researchers looked at the children when they were ages three, five, seven, nine, 11 and 12 years old.

At age three, the children took part in a test of their self-control. They were left sitting alone in a room with several toys, one of which they were asked not to touch until an adult returned. Those who waited at least 75 seconds before playing with the toy were considered high in self-regulation.

Then at age five, the children participated in a similar exercise in delayed gratification that involved the choice between a smaller portion of a favourite food immediately or a larger amount after several minutes.

Compared with children who showed high self-control and were able to wait at least 210 seconds before diving in, children who were unable to wait at both ages had the highest body mass index scores for their age at 12 years, and the fastest increases in BMI over the nine-year followup, the researchers found.

"In essence, it appears that children with greater self-regulation tend to be leaner, smarter, and better able to get along with others," Dr. Robert Whitaker and Rachel Gooze of Temple University in Philadelphia said in an editorial accompanying the research.

More treats if you wait

A second study tested the ability to delay gratification among four-year-olds.

The children were left alone with two plates containing different quantities of their preferred food — candy, animal crackers or pretzels.

Participants were told they could eat the larger quantity if they waited until the examiner returned. If a child couldn't wait, he or she was told to ring a bell to summon the examiner back, and then eat the small quantity.

About 47 per cent of the 805 children failed the test, either by ringing the bell before the seven-minute waiting period was up, spontaneously beginning to eat the food, becoming distressed or going to the door to call a parent or the examiner.

Those who showed a limited ability to delay gratification were 29 per cent more likely to be overweight at age 11, a link that was partly explained by their mother's weight, the researchers said.

"The influence of maternal weight status on child weight reflects genetic as well as environmental factors, such as feeding patterns and availability of food," Desiree Seeyave of the University of Michigan, Ann Arbor, and colleagues wrote.

They suggested parenting strategies to help children develop an ability to delay gratification, such as:

• Keeping the desired food out of sight and therefore out of mind.
• Distracting the child's attention from the food and toward another engaging activity.
• Offering a logical structure to snacks and meals, so the child learns to wait to eat until the next snack or meal time.

A child's ability to self-regulate can be changed, Whitaker and Gooze said in their editorial.

"Self-regulation is shaped by both nature and nurture; it is influenced by environments and experiences during early childhood."

While there aren't yet any proven ways for improving children's capacity to self-regulate, there are promising results from randomized controlled trials that show ways of boosting preschoolers' positive social behaviours, they said.