Thursday, August 04, 2011

The cost of nutrients

Pablo Monsivais, Anju Aggarwal, and Adam Drewnowski have a fascinating new study out today in the journal Health Affairs.  Using data from surveys in Seattle, it found that diets were more expensive for people who consumed higher amounts of certain nutrients, such as potassium, and lower amounts of other food components, such as saturated fat.
Our findings highlight a stark economic dimension to observed imbalances in diet. Based on the diets reported by a representative sample of King County, Washington, residents, our analyses indicate that people attempting to bring their diet closer to recommended consumption levels for the nutrients we studied would probably have to pay higher food costs.
The nutrients themselves are not expensive.  In a 2009 study of diet models using the framework of USDA's Thrifty Food Plan, Joseph Llobrera and I explored different types of economic and nutritional constraints that one could try to meet. While choosing diets that are as similar as possible to current consumption patterns, it is fairly inexpensive to meet just nutrient constraints (like getting enough calcium and sufficiently low saturated fat).  It is a bit more expensive to meet Pyramid food group constraints (like getting enough fruit).  And it is more expensive still to meet idiosyncratic food-specific constraints (like getting enough of particular red meats).

The Health Affairs article is getting nationwide coverage today from the Associated Press, under the headline: "Healthy Eating is Privilege of the Rich, Study Finds." I am quoted for opposition to the main thesis.  Journalists do this in part because of the intrinsic value of multiple points of view, and also for narrative tension, quoting one scholar against another.  It is more fruitful to see this as an ongoing conversation in a community of researchers, trying to identify the economic and non-economic sources of unhealthy eating patterns, and reading each other's work with great interest and appreciation.

Addendum: Still mulling over this discussion, a good way to think quantitatively about these questions is to fiddle with our Thrifty Food Plan Calculator, on the Friedman School website.  For example, the tab titled "good sources of..." has a list of the food groups that provide the most potassium per dollar, the most fiber per dollar, and the least saturated fat per dollar.  These are the nutrients that featured most prominently in the Health Affairs article.  Enjoy exploring.


cmac611 said...

Interested in your comments (and thesis) on this subject which is near and dear to my heart! I posted a the following comment to Pablo's article ... "'I'd like to see the actual data ... personally, I think you can eat 'exceptionally' healthy for a reasonable cost! It takes effort and discipline (something we seem to lack of late). I have a 5yr food diary and vitals to know that for about $13.50/day I can eat 2175 calories (1674 net after exercise) which includes 80gm fiber, 85gm protein, 2100mg sodium; no HFCS, processed or packaged foods, artificial sweetener, etc.); and a mix of organic, local, fresh, and frozen. Not sure, but my time to prepare meals might not be that much different than going to nearest 'drive through.' Like I said, takes a little effort, discipline, and add to that a pinch of personal responsibility to take care of your body and not expect our wonderful 'sick care' system to fix your 'preventable' ailments." How does my cost compare to your research (realize you might be missing some important info, but nonetheless generally speaking).

Thanks, Charles

Parke Wilde said...

That's fascinating.

There is no reason for each person to make the same tradeoffs. You get high-quality and healthy meals at moderate cost through discipline and efficient home preparation. Others choose a healthy diet with more prepared foods and eating out, at greater expense. Still others eat convenient foods inexpensively, but sacrifice the freshness, organic production, and health profile.

It would be nice if it were possible to have great healthfulness, good taste, high quality, and high convenience, at low expense, with little need for cooking knowledge and discipline. But perhaps the policy goal should be more humble than all of that.