The minister for public health has sought to frame the debate about obesity in socioeconomic terms, saying it was "heartbreaking" that many families who were at the greatest risk of obesity were also among the country's poorest.

Anna Soubry, who has welcomed pledges by soft drinks brands Lucozade and Ribena to reduce the sugar in some products, said the situation had changed from her schooldays, when the demography of children could be gauged by how thin they were.

"When I go to my constituency, in fact when I walk around, you can almost now tell somebody's background by their weight," she told the Daily Telegraph. "Obviously, not everybody who is overweight comes from deprived backgrounds but that's where the propensity lies. It is a heartbreaking fact that people who are some of the most deprived in our society are living on an inadequate diet. But this time it's an abundance of bad food."

Soubry also called for parents to exercise more discipline when it comes to insisting their children take part in family meals. She said that a culture of "TV dinners" had eroded traditional structures of family life and led some homes to dispense with a dining table entirely.

The minister suggested some parents thought cheap junk food was the only way to feed their children. She said she saw parents buying their children unhealthy "breakfast buns" from fast food shops on her way to work at Westminster.

England has some of the highest obesity rates in the developed world, with 60% of adults and one third of 10- and 11-year-olds being overweight or obese.

Successive studies have shown that the poorest are most likely to be obese. They included one by the University of Glasgow which found that residents of an impoverished Glasgow neighbourhood were more than twice as likely to be obese compared with residents of an affluent neighbourhood only miles away.

Soubry's comments came after she threatened food manufacturers with legislation unless they cut the amount of fat, sugar and salt in products.