A total ban on TV advertising of food and drink to children has been ruled out by the telecoms regulator.
There is concern about children's diets
Ofcom said other measures, such as encouraging exercise, would be a better way to tackle child obesity than a total ban on TV ads.
But it will consider amending current rules after the publication of a White Paper on public health later this year.
It also wants to consider a Food Standards Agency report into the nutritional values of different foods.
Stephen Carter, Ofcom chief executive, said: "Childhood obesity is a public health concern which experts in nutrition, health and education, the government and the food industry are rightly addressing.
"Television advertising clearly has an influence and equally clearly there is a need for a tightening of specific rules. However, a total ban would be neither proportionate nor, in isolation, effective."
Culture Secretary Tessa Jowell asked Ofcom to look at the issue of food advertising directed at children last December.
However, she said in March this year she was "sceptical" about whether a ban would combat obesity.
The Ofcom research found that most parents:
- Do not support an outright ban on television advertising
- Support the need for better information about the nutritional
content of the products being advertised
- Would like advertisements directed at young children to be less
attractive, for example by avoiding the use of cartoon characters
- Support the use of targeted scheduling restrictions
The regulator commissioned more than 2,000 interviews with children, parents,
teachers and nutritionists to explore why children choose the food they do, how food promotion influences this, and the key messages children take from television.
It also asked an independent expert - Professor Sonia Livingstone of the
London School of Economics - to conduct a full review of relevant academic research.
The study found that television advertising has a modest direct effect on children's food consumption.
However, the significance of this is small when compared to other factors potentially linked to childhood obesity such as exercise, trends in family eating habits inside and outside the home, and school policy.
The research also found that 70% of children's viewing takes place outside of officially defined children's airtime.
Ofcom raised fears that a ban would remove the right to advertise products that could potentially have a positive impact on health
And it would undermine the likely investment in children's programming on commercial television, reducing choice and innovation for younger audiences.
The Ofcom decision disappointed the British Medical Association, which called for a complete ban on all food advertising aimed at children under 12 at its annual conference last month.
Dr Peter Maguire, of the BMA's Board of Science, said: "Ofcom's own research clearly states that TV advertising has an effect on children's eating habits, yet they refuse to recommend a ban.
"We are in the midst of an obesity epidemic and must use all the tools in our armoury to prevent the next generation of British children being the most obese in history.
"Obesity in children stores up a lifetime of poor health. These children are at greater risk of having high blood pressure, developing diabetes and heart problems.
"Surely the health of our children is more important than advertising revenues?"
In May, in their report on obesity, the Commons Health Committee also called for a voluntary withdrawal of TV advertising of junk food to children.
Martin Paterson, deputy director general of the Food and Drink Federation, said he would carefully study the review.
"We are clear that we need tight, workable advertising codes.
"We agree that a ban would be neither proportionate nor effective, and look forward to participating in the consultation."
Mary MacLeod, chief executive of the National Family and Parenting Institute, said it backed the rejection of a total ban.
Bur she said: "The number of television adverts that promote unhealthy foods to children show that targeted intervention is required.
"We strongly recommend that advertising to young children; and the advertising of junk foods, is banned. Our research shows this would have strong support from parents."