A think-tank claims children from poor homes should get free healthy meals during the summer holidays to cut levels of obesity.
Ippr North said that holiday clubs could give the food to impoverished youngsters who are normally entitled to free school dinners.
It believes the move will encourage improved eating habits among the poorest children, who are also the most likely to be obese.
Sue Stirling, director of Ippr North, said: "Extending free meals to holiday clubs for the poorest children would help encourage good eating habits all year round, and improve concentration and learning during term time.
"In the holidays, many poor children are eating cheaper and energy-dense food, but are being nutritionally deprived.
"We shouldn't be blaming poorer parents: we should be helping them meet the cost of healthy alternatives."
The group added almost one in five children living in the most deprived areas are obese, compared with just under one in seven of those in the least deprived places.
Department for Children, Schools and Families minister Kevin Brennan said: "The government has invested almost £500m in healthy school meals, provides free fruit and vegetables, and young people can access out of school hours activities, such as breakfast clubs, both in term time and during the school holidays through the extended schools programme."