With the obesity epidemic breaking out of control, experts are calling for radical measures including restrictions on fast food outlets.
Dr Stephen Monaghan, public health director of Cardiff Local Health Board, has called for a debate about what type of restaurants are granted high street planning permission.
He said, "We need to be thinking about the future environments and there is an issue here about planning permission, particularly for fast food outlets.
"I'd like to see whether anything could be done about that - we should at least be having a debate about it. We currently only think about these places in terms of food safety and not giving people food poisoning, but that's not enough.
"Fast food restaurants may be useful for developments as they will often pay good rental charges, but we need to be thinking beyond where we are now."
Almost one in five 13-year-olds in Wales is classed as overweight or obese - higher than in England, Scotland and Ireland. And some 30 children in Wales have been diagnosed with type 2 diabetes, a condition which only used to be associated with the over-40s.
Six out of 10 men and 50% of women are already either overweight or obese, but the recent Foresight report has predicted that, if current trends continue, 60% of men and 50% of women will be obese by 2050 at a cost to the UK of Ģ45bn a year.
Dr Paul Walker, chair of the Public Health Association Cymru, said, "Obesity and overweight is undoubtedly the second greatest public health challenge in developed countries like the UK after smoking.
"We seem to be winning slowly with smoking, with rates continuing to decline - though less so in women than in men - but we are getting nowhere, it seems, with obesity and overweight.
"Part of the problem is that the epidemic is not taken seriously enough at any level, perhaps because there is no quick fix.
"The solution is multi-faceted ranging from policies to promote physical exercise through to greatly improved integrated public transport and increased disincentives for motor car use to far stronger regulation of food supply and advertising.
"None of these measures will be immediately popular but then the same was true of the early measures against smoking.
"It is a battle for the long-term but the sooner we start the sooner we will begin to have an impact."
Dr Tony Jewell, Wales' chief medical officer, said, "The Welsh Assembly Government aims to make it easier to make healthy living choices whether that be the food we eat or the amount of exercise we take.
"Our efforts are to try to change habits, by encouraging people to choose healthy option foods rather than foods high in fat, salt or sugar, and to take exercise such as walking or cycling instead of using the car.
"Planning can be effective indirectly to help improve people's health and well-being such as minimising the need to travel by car by locating housing, jobs and facilities within walking or cycling distance.
"Local authorities do have environmental health and licensing powers which can be applied to control operation of fast food establishments but this is more about food hygiene than tackling the culture of processed and fast food."