How Do You Compare Happiness? First, Check Your Blood Pressure.

"Happy countries seem to have less hypertension."

That's the intriguing money quote in a new paper (pdf here) that looks at happiness measurement across countries, and concludes that high blood pressure is reliably inversely correlated to happiness. That means that it will be far easier to compare national happiness levels -- future researchers can use objective data gathered at the doctor's office rather that subjective ratings collected through expensive surveys.

People in the former East and West Germany, Portugal, and Finland have high blood pressure. Those same countries have relatively few people who say they are "very satisfied" with their lives. The opposite hold true for Ireland, Denmark, the Netherlands, and Sweden -- they're full of happy, healthy people.

There has been discussion of how to measure "gross national happiness," and the paper by Dartmouth's David Blanchflower of Dartmouth and Andrew Oswald of Warwick University (UK) may show the way.

Among other statistical adjustments, they sought to account for the availability of health care so that wouldn't skew the results.

They also note that, as always with correlations of this type, causality is hard to prove. It could be that nations whose citizenry have high blood pressure and, perhaps, related health problems, are not happy. It may be that it's not unhappiness that causes high blood pressure, but poor health that causes unhappiness. The authors allow that more research is needed to make their case definitive.