Laws limiting the amount of sugar, salt and fat in food should be considered, a leading Labour politician has urged.
Andy Burnham, the shadow health secretary, has begun a consultation on how to tackle obesity.
Labour says voluntary agreements within the food industry are not working, and that politicians should look at banning children's foods that have a high sugar content, the Daily Telegraph said.
Burnham highlighted the case of breakfast cereals, saying that many aimed at children are more than one-third sugar by weight.
He said: "Like all parents, I have bought products like cereals and fruit drinks, marketed as more healthy, that contained higher sugar levels than expected.
"I don't think that any parent would be comfortable with their child eating something that is 40% sugar."
Burnham has begun consulting with the public and experts on the issue, and is considering proposing a 30% cap on sugar in cereals.
He warned that the rise in obesity was "storing up huge problems for the country and the NHS in the long term", and said the Government had failed to tackle the epidemic.
But the Department of Health said it has helped reduce the levels of fat, sugar and salt in foods.
A Department of Health spokesman said: "By working with industry through the Responsibility Deal we have helped to reduce fat, sugar and salt in foods.
"There is now less salt in the food we buy, companies are cutting and capping calories and artificial trans fats are being widely taken out of food."
The spokesman added: "We are working to reduce the amount of salt in food further, cut saturated fat consumption and we are exploring how to promote healthier food choices more widely. We also want more businesses making pledges so we get bigger results."