Hull schoolchildren are healthier as result of the city's free school meals trial, an interim report is expected to say in December.
No hard findings have been released yet, but Mary Glew, a Labour councillor and former Cabinet member for health, said there was anecdotal evidence that children were taller and slimmer two years into the plan.
Her comments come as the Liberal Democrat council backed down from its vow to scrap the £3m-a-year project without examining the potential benefits. After a 29-25 defeat in council last week, the Lib Dems said they would wait for further evidence before deciding.
Glew pointed to improvements in behaviour and attendance since school meal uptake increased from 36% to 64%.