Professor Annie Anderson says the availability of cakes and sweets has risen considerably, with planners “turning a blind eye” when approving new fast food outlets, tea shops and cafes.
She said people need help to make lifestyle changes such as going for a 20-minute walk every day or “ditching the biscuit”.
Anderson, who is based at the University of Dundee, has been elected as president of the UK Society for Behavioural Medicine, an academic body who respond to consultations from both the Westminster and Scottish governments on initiatives to improve public health.
She will take up her post next week when she addresses the society at a meeting in Birmingham.
Researchers from the University of Strathclyde recently estimated that more than 100,000 Scots children and young people are obese.
A Body Mass Index (BMI) of between 30 and 40 is classed as obese, with 29 per cent of Scots adults aged 16 or over falling into this category.
Anderson said she could think of “ten places in any high street where you can now buy a cake” and described the number of new cafes opening up as “huge”.
On top of increased availability she also criticised deals promoting “junk food” and questioned how much food labelling influences behaviour – particularly in socially deprived areas.
She said: “We have to remember that promotions are one part of what influences what we are buying. Obviously the cost is important, but also the availability.
“It never fails to amaze me that we can get sweeties in just about every shop you go into in the high street, whether it’s a charity shop or clothes shop or whatever.
“We really need to think long and hard about whether there should be some restrictions going on.”
Anderson said it was “very normal” to be overweight in Scotland and a huge amount of work is being done to encourage people to cut down on sugar.
She added: “Everything we do in our individual lives is around eating and being less active.
“I would say probably around 80 per cent of obesity is related to food rather than physical activity.
“Everybody talks about their Auntie Jean who lived to be a ripe old age: she smoked, watched television and never had a piece of fruit. There are people like that, no doubt, but there are very few of them.
“Also, everybody talks about someone else who lived healthily but got breast cancer aged 50, and unfortunately you do get those people as well.
“We know, for example, with something like breast cancer – someone who does all the right things is 70 per cent less likely to get the illness.
“So it doesn’t mean they won’t get it but it reduces the odds of that happening.”
Ewan MacDonald-Russell, head of policy at the Scottish Retail Consortium, said measures to restrict future planning applications will have “no impact” on existing businesses and could be a barrier to businesses who aim to responsibly sell healthy products as well as treats.
He added: “Our industry has led the way on reformulating products to reduce salt, sugar and fat from products, and in finding the best and clearest ways to give consumers nutritional information.
“The reality is that the causes of obesity are highly complex, and require proportionate and evidence-based responses.
“We have been clear evidence should be robust, specific, and that any measures taken should apply across the food and drink industry and in the public and education sectors.”