This is not evidence a sugar tax works

Dita De Boni writes:

For a start, a sugar tax is out. Dr Coleman says there’s no evidence it works.

That’s wrong.

Really? Dita’s proof:

It’s well documented that countries serious about obesity have embraced sugar taxes, and those taxes have reaped rewards (and raised revenue). In Mexico, in just one year, the population of the world’s biggest soft drink consumers bought 12 per cent less fizzy.

That’s not proof it is leading to less obese Mexicans. The aim presumably is to reduce obesity, not reduce soft drink sales. Well actually for some I think it is the latter.

Many other beverages such as orange juice, beer and milk are also high calories. A reduction in sales for one sources of calories may have absolutely no impact on obesity.

It also made the Mexican Government more than US$1 billion ($1.49 billion) in tax to put towards further obesity work.

If your aim is to increase the amount of tax people pay, then yes a sugar tax works. But that is not proof that it reduces obesity.

One in six Mexican adults have diabetes. Has the soda tax reduced that proportion? Has it reduced obesity? That is evidence it works, not the fact it decreases sales and increases tax.