7 flaws in Mexican soda tax

A single study is being quoted around the world as the case for taxing soda.

Its catchy title is “Beverage purchases from stores in Mexico under the excise tax on sugar sweetened beverages : observational study.”

There appear to be two key flaws in the research:

1 Its methodology was to survey a sample of consumers rather than assess the total market.

2 Its findings conclude that “a major limitation of this work is that causality cannot be established.”

A third flaw is in the tax itself.

3 Consumers still pay the same price for a diet variant as for a regular soft drink.

The fourth flaw, to me, is the biggest misconception.

4 Even if it had changed behaviour, it hasn’t made a material contribution to tackling obesity.

There are three final flaws in the Mexican tax :

5 It hurts poorer consumers more.

6 It distracts Government attention because of the huge sums raised.

7 It delays other action to solve obesity, while everyone waits to assess its inadequate impact.