On 30 January 2018, a report from Peter Wilson and Sarah Hogan, commissioned by the Ministry of Health of New Zealand to review the evidence around the efficiency of sugar taxes. It concluded that evidence that sugar taxes improve health is weak.

Among the key conclusions from the report, authors underline that:

  • There is insufficient evidence to judge whether consumers are substituting other sources of sugar or calories in the face of taxes on sugar in drinks
  • Studies using sound methods report reductions in intake that are likely too small to generate health benefits and could easily be cancelled out by substitution of other sources of sugar or calories
  • No study based on actual experience with sugar taxes has identified an impact on health outcomes
  • Studies that report health improvements are modelling studies that have assumed a meaningful change in sugar intake with no compensatory substitution, rather than being based on observations of real behavior
  • The evidence that sugar taxes improve health is weak

The full report is available here.