The greatest effects may occur in young people, with no significant differences between income groups. Both effects warrant further exploration, according to researchers, who concluded taxation of sugar sweetened drinks is a promising population measure to target obesity, particularly among younger adults.
The primary outcomes of this econometric and comparative risk assessment modeling study were overall and income specific changes in the number and percentage of overweight (body mass index ≥25) and obese (≥30) adults in the U.K. following implementation of the tax. Secondary outcomes were the effect by age group (16-29, 30-49, and ≥50 years) and by U.K. constituent country. The revenue generated from the tax and the income specific changes in weekly expenditure on drinks were also estimated.
A 20% tax on sugar sweetened drinks was estimated to reduce the number of obese adults in the U.K. by 1.3% (95% credible interval 0.8% to 1.7%) or 180,000 (110,000 to 247,000) people and the number who are overweight by 0.9% (0.6% to 1.1%) or 285,000 (201,000 to 364,000) people. The predicted reductions in prevalence of obesity for income thirds 1 (lowest income), 2, and 3 (highest income) were 1.3% (0.3% to 2.0%), 0.9% (0.1% to 1.6%), and 2.1% (1.3% to 2.9%).
The effect on obesity declined with age. Predicted annual revenue was £276m (£272m to £279m), with estimated increases in total expenditure on drinks for income thirds 1, 2, and 3 of 2.1% (1.4% to 3.0%), 1.7% (1.2% to 2.2%), and 0.8% (0.4% to 1.2%).