A tax on biscuits, cakes and sweets might be more effective at reducing obesity levels than increasing the price of sugar-sweetened drinks, latest research suggests.

The study, published in the BMJ, found that high-sugar snacks made up more free sugar and energy intake than fizzy drinks. Researchers used economic modelling to assess the impact of a 20% increase on high-sugar snack foods in the UK.

Raising the cost by 20% would help reduce annual average energy intake by around 8,900 calories and lead to an average weight loss of 1.3kg (2.8lb) over one year, researchers claimed.

In contrast, a similar price increase on sugary drinks would result in an average weight loss of just 203g over one year.

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 findings suggested a reduction in purchases of high-sugar snacks had the potential to make a greater impact on population health than reducing the purchase of sugary drinks.

The option “is worthy of further research and consideration as part of an integrated approach to tackling obesity”, the researchers said.

In the UK, obesity is estimated to affect around one in every four adults and around one in every five children aged 10 to 11, with higher rates among those living in more deprived areas.

Last month Action on Sugar and Action on Salt called on the government to introduce a tax on all calorie-dense processed foods that meet agreed criteria.

In January a poll of 2,000 Brits by Mintel found that six in 10 supported taxes on unhealthy food and drink, such as the levy introduced on soft drinks last year.

Scots bring forward restrictions on HFSS promos

Meanwhile, the Scottish government is to bring forward legislation to restrict the promotion and marketing of food and drink high in fat, sugar or salt [HFSS].

Making the announcement in parliament this week, First Minister Nicola Sturgeon said the Bill on Restricting Food Promotions would be introduced in 2020’s legislative programme.

The move was welcomed by Action on Sugar campaign director and nutritionist Katharine Jenner.

"We applaud Nicola Sturgeon’s announcement that she will be putting unhealthy food in the spotlight and legislating to restrict HFSS food and drink promotions, and urge our government to follow suit,” she said.

“The current UK regulations have major loopholes, allowing aggressive advertising and promotions to cast unhealthy options in a starring role in children’s minds, leaving healthier food options in the background. To set the stage for good health, it is vital that only non-HFSS foods and drinks can be marketed and promoted, including in-store price promotions and sweets at the checkouts."