A scheme that helped parents plan well-balanced family dinners for three months kept their children healthier for years after, a study has found.

Low-income families who were given simple recipe kits to cook five healthy meals a week decreased their children’s body mass index (BMI) compared with peers who continued their normal eating patterns.

Another initiative that encouraged families to eat meals at regular times of day and cut out snacks for three months had a similar impact on children’s BMI during the first year, but its benefits faded over time.

Children continued to adopt a regular diet and to eat healthily after the programmes ended, there was no evidence of a similar change in their parents, researcher found.

Some 285 families in Edinburgh and Colchester took part in the study. They were asked to follow either of the programmes for 12 weeks or to carry on as usual. Researchers monitored their progress for three years afterwards.

Prior to the treatments, all the adults and children involved were eating too much saturated fat and sugar and not enough fruit and vegetables.

Experts from the universities of Bath and Edinburgh collected information on their dietary habits, weight and BMI. They found that children in the families using the meal kit or set meal times fell in the BMI distribution by 5 to 6 percentage points, achieving a healthier weight in relation to their height.

The results suggest that healthy dinners are an affordable and nutritious option even for families with limited finances, researchers say. Poor diet is a major global issue, accounting for an estimated 11.3 million deaths per year.

Dr Jonathan James from the University of Bath’s Department of Economics explained: “Recent work from the medical literature has shown how a poor diet is now the leading cause of early death. In our study we tried two ways to develop healthy eating habits and preferences among families with young children some of who were pre-school age. We did this by changing what they ate by providing free healthy meals for three months and by changing the frequency of eating by getting the families to stop snacking and to eat at regular times.

“While the results are encouraging for the children, the parent’s habits and preferences remained remarkably stable."

Professor Michèle Belot, from the University of Edinburgh’s School of Economics, who led the study said: “Our results suggest that dietary habits are more malleable early on in life than later. We found that children in both groups moved down in the distribution of body mass index. Interestingly, it appears possible to affect children’s habits even if those of their parents are unchanged.”