Writing in the British Medical Journal today, researchers say that this option “is worthy of further research and consideration as part of an integrated approach to tackling obesity”.
Obesity rates are increasing around the world.
In the UK, obesity is estimated to affect about one in four adults and around one in five children aged 10 to 11, with higher rates among those living in deprived areas.
In Scotland around 29 per cent of children are at risk of becoming overweight (including obese), with researchers from the University of Strathclyde having estimated that more than 100,000 young Scots are obese.
The use of taxes to lower sugar and energy intake has mainly focused on sugar sweetened drinks.
But in the UK, high-sugar snacks, such as biscuits, cakes, chocolates and sweets, make up more free sugar and energy intake than sugary drinks.
Reducing purchases of high-sugar snacks therefore has the potential to make a greater impact on population health than reducing the purchase of sugary drinks.
To explore this in more detail, researchers used economic modelling to assess the impact of a 20 per cent price increase on high-sugar snack foods in the UK.
Modelling was based on food purchase data for 36,324 UK households and National Diet and Nutrition Survey data for 2,544 adults.
Results were grouped by household income and body mass index (BMI) to estimate changes in weight and prevalence of obesity over one year.
The results suggest that, for all income groups combined, increasing the price of biscuits, cakes, chocolates and sweets by 20 per cent would reduce annual average energy intake by around 8,900 calories, leading to an average weight loss of 1.3 kg over one year.
In contrast, a similar price increase on sugary drinks would result in an average weight loss of just 203g over one year.
Powers to introduce such levies are reserved to the UK Government.
However, a Scottish Government spokesperson said: “Overconsumption of products such as snacks and sugar-sweetened beverages is directly contributing to high levels of obesity in Scotland.
“Tackling obesity is a public health priority and our Diet and Healthy Weight Delivery Plan includes specific measures to help families make healthier choices.
“This includes introducing a Restricting Foods Promotions Bill before the end of this parliamentary session.”