Thursday, December 9, 2010

Did the Great Recession Put Men on a Diet?

Here's something intriguing I noticed while poking around the website of the Center for Disease Control.  Every few years, there is a survey called the National Health and Nutritional Examination Surveys.  One of the things this survey measures is the average daily caloric intake of the population - both men and women.  There are two analyses of this data that I found - one here for 1970-2000, and another here for 1999-2008. The two analyses are not directly comparable (I believe because of differences in how age adjustment is done, and which age groups are included).  Thus I have plotted them separately on the above graph (as I and II respectively).  The second survey produces lower values.

The thing that caught my eye is the sharp drop in male caloric intake between the 2005/2006 survey and the 2007/2008 survey (after decades of mostly increasing food consumption).  This is the green circle in the graph.  It's possible, I suppose, that some men suddenly got religion about healthy eating in the last couple of years.  But I'm more inclined to suspect recession induced belt-tightening (literally, perhaps).

It would take a more careful analysis of the underlying raw data to confirm this (eg was the reduction in eating concentrated amongst the newly unemployed or poor?), but I thought it was an intriguing possibility.  If true, recessions in modern times might have unexpected benefits in reducing future health costs.


Dean said...

It wouldn't surprise me if this was related to a reduction in restaurant eating, considering how crazy huge the caloric intake is for meals at restaurants.

Unknown said...

This seems very odd as 2007-2008 is too early a period to see this effect. If we had such results for 2009-2010, I'd have thought many newly unemployed previously manual workers had reduced their caloric intake - just because they burned less calories.

Stuart Staniford said...

Christian: the recession formally began in Dec 2007. There was also a significant food price spike before that.

Michael Ayers said...

This comment has nothing to do with any effects of the recession, but those data seem strange to me.

I remember reading a few years ago that the average daily caloric intake in the US was over 4,000 Cal. I can't remember where I saw that, but I did find an Excel spreadsheet from the
Food and Agriculture Organization of the United Nations
Statistical Yearbook that lists energy intake by country.

The US leads the field at 3826 Cal for the 02003-5 time period, though several other countries are right up there.

How is this reconciled with the CDC data? Given the rate of obesity in the US, I can't believe that US women take in <2000 Cal/day (or men <2700) unless those data also inlcude children or elderly.