Published: 05 September 2019
Increasing the price of high-sugar snacks such as biscuits, sweets and cakes could be a more effective way to reduce levels of obesity than taxing sugar-sweetened drinks, suggests new research funded by NIHR’s Policy Research Programme.
The study, published in The BMJ, used economic modelling to predict the impact of a 20% price increase on high sugar snack foods in the UK.
The results suggest that this price increase would reduce average energy intake over the course of a year by around 8,900 calories across adults in all income groups, leading to an average weight loss of 1.3kg over a year. A similar price increase on sugary drinks would result in an average weight loss of 0.2kg.
The researchers looked at food purchase data for 36,324 households and survey information on adults’ food intake for 2,544 adults from the National Diet and Nutrition Survey. Three categories of high sugar snacks were included - biscuits, chocolates and confectionery, and cakes (not including larger cakes meant for sharing).
In the UK, around 1 in 4 adults are estimated to be obese, with higher rates among lower income groups. Obesity increases the risk of many diseases including diabetes, cardiovascular disease and several types of cancer.
The results predict that the impact of a ‘sugar tax’ on snacks would be largest in low income households with the highest rates of obesity, suggesting that this approach could help to reduce health inequalities driven by diseases related to diet.
Lead researchers Dr Pauline Scheelbeek and Dr Laura Cornelsen, both based at the London School of Hygiene and Tropical Medicine, comment that a price increase for high sugar snacks “has the potential to reduce overall energy purchased among all body mass index and income groups in the UK, leading to an estimated population level reduction in obesity prevalence of 2.7 percentage points after the first year.
“The results also suggest that price increases in high sugar snacks could also make an important contribution to reducing health inequalities driven by diet related disease.”
In a linked editorial, the researchers say there is a strong rationale for using policies such as a ‘sugar tax’ to improve diet and health, but that caution is needed because the ways in which people may switch to other foods can be difficult to predict.