Healthy living vouchers: will they work?

Matt Ridley writes:

Drawing a direct analogy with the effect of vouchers in the education system, Messrs. Seeman and Luciani suggest “healthy-living vouchers” [TC: book is here] that could be redeemed from different (certified) places—gyms, diet classes, vegetable sellers and more. Education vouchers, they point out, are generally disliked by rich whites as being bad for poor blacks—and generally liked by poor blacks. A bottom-up solution empowers people better than top-down government fiat.

So instead of spending large sums on ads to shame us into better eating habits, spend the money on vouchers handed out to the overweight and let them find whatever provider of goods or services best meets their particular dieting needs. After all, the root causes of obesity are multifarious and new ones are being added all the time—such as diet sodas, gut bacteria, genes, sleep apnea, leptin levels, medication, depression, poverty and peer pressure. So the solutions need to be multipronged, too. What works for you may not work for me.

A few points:

1. How exactly does one identify who deserves the voucher?  Or does everyone get them?  (Do we at this point need another middleclass entitlement?)  How much does the price of the good stuff go up?

2. The vouchers can be resold on secondary markets, as food stamps often are.

3. Portfolio effects: the unhealthy person might go to the gym with a voucher and then “make it up” by performing more of the unhealthy behaviors as recompense.

4. Income effects: if the voucher boosts the real income of the unhealthy person, they may well end up buying more stuff which is bad for them.  I don’t see that the proposal calls for a simultaneous, income-neutral scheme of taxation.  Buying more bad stuff and also more good stuff is not a wash, which brings us to:

5. It is easier to destroy than to preserve health, which suggests limiting the bad, or persuading individuals to limit the bad, will create more health benefits than encouraging the good.

I’m all for creative thinking here, but it’s hard to see this proposal working.  If nothing else, though, it shows why this problem is so hard to solve.