What was the biggest health care breakthrough in the last 40 years in the United States? Heart bypasses? CAT scans and M.R.I.’s? New cancer treatments?

No, it was the cigarette tax. Every 10 percent price increase on cigarettes reduced sales by about 3 percent over all, and 7 percent among teenagers, according to the 2005 book “Prescription for a Healthy Nation.” Just the 1983 increase in the federal tax on cigarettes saved 40,000 lives per year.

In effect, the most promising cure for lung cancer didn’t emerge from a medical research lab but from money-grubbing politicians. Likewise, the best cure for obesity may turn out to be not a pill but a tax.

- Nicolas Kristof on The Soda Tax