New research has shown a link between stress, hormones, diet and increasing body fat in children.

The research, by scientists at Ghent University In Belgium, suggests managing stress in addition to other lifestyle factors could be an effective measure to combat obesity in children.

The researchers studied the effect of children's stress on diet and body fat levels and and found that the stress hormone cortisol might directly influence rises in body weight or might indirectly lead to less healthy dietary intake.

"This dietary change may be due to a higher appetite and desire for reward through resistance to the satiety (fullness) hormone leptin." the researchers said.

In the study, 312 Belgian children aged 5-12 years had their stress-diet-body fat relationship studied. At the beginning of the study, samples of saliva were taken from each child to measure levels of cortisol.

The researchers found that children with a high stress score reported more sweet food consumption, emotional eating, external eating in response to food and restrained eating.

Importantly, stress increased body fat only in children with high sweet food consumption or high cortisol, the researchers said.

They added that high levels of the cortisol were associated with an unhealthy diet and with higher leptin levels in the girls studied.

The researchers concluded that children's stress makes their diet less healthy, which stimulates increases in body fat.

The research was presented at the European Congress on Obesity (ECO) in Sofia, Bulgaria,