Donuts vs. Broccoli
Ezra Klein points to a two-year-old paper titled “Cheap Donuts and Expensive Broccoli: The Effect of Relative Prices on Obesity.”
The abstract, which is all I’ve read:
Americans have been getting fatter since at least the mid 1980s. To better understand this public health problem, much attention has been devoted to determining the underlying cause of increasing body weights in the U.S. We examine the role of relative food prices in determining an individual’s body mass index, arguing that as healthful foods become more expensive relative to unhealthful foods, individuals substitute to a less healthful diet. Using data from the National Health Interview Survey (NHIS) for the period 1982-1996, we find that individual BMI measures, as well as the likelihood of being overweight or obese, exhibit a statistically significant positive correlation with the prices of healthful relative to unhealthful foods. These results are robust to endogenizing the relative price measure. While the magnitudes of our estimates suggest that relative price changes can only explain about 1 percent of the growth in BMI and the incidence of being overweight or obese over this period, they do provide some measure of how effective fat taxes would be in controlling the obesity epidemic. Our estimates imply, for example, that a 100 percent tax on unhealthful foods could reduce average BMI by about 1 percent, and the same tax could reduce the incidence of being overweight and the incidence of obesity by 2 percent and 1 percent respectively.
So, in answer to the title’s implicit question: Negligible, indeed. Which, really, it doesn’t take either a PhD or a research grant to figure out.
Thought experiment: You’re offered two plates. On one, there’s a heaping of steamed broccoli. On the other are two fresh, hot donuts from Krispy Kreme. They’re both free. Which would you take?
UPDATE: And, no, of course there’s no butter on the broccoli. Maybe a touch of lemon.
Uh, er…………how about in the mid 80’s the baby boom bulge was 30-35 years old. Now they are 55-60.
A pound a year is what the docs say……
The choice would entirely depend on the time of day. I like both donuts and steamed broccoli (particularly with a dab of butter and some pepper), but I wouldn’t eat the former after noon or the latter before lunch.
T. Jaxon: Nothing personal meant, but that “dab of butter” with the broccoli (that almost no one ever talks about) is the real culprit for those fighting weight gain 😉
I would probably rather have the broccoli raw, but I agree it depends on the time of day.
I do think there is something to unhealthy foods being cheaper-and this goes to veggies. A 10 lb bag of potatoes goes further than an equivalent price in broccoli and can feed more people, but is nutritionally less healthy. A box of mac and cheese is cheap compared to fresh vegetables-shoot even compared to a can of vegetables and is dirt cheap.
If you are living on a budget-high carb, high fat foods are going to be cheaper in general than healthier choices-especially fresh produce (at least where I live, in the south some veggies can be purchased rather cheaply at farmer’s markets and the growing seasons are much longer).
Personally, I strongly discount anything that relies on BMI. It is a completely bogus measure.
Oh, and please tell all the little coffeehouse commissars that taxing all of us great unwashed to make us behave the way they think we ought to may not produce quite the effect they were looking for.
By the way. A chemical in broccoli (and cabbage, kale, cauliflower etc) called indole 3 carbinol is said to be important to phase two metabolism of fat soluble to water soluble toxins in the liver. In the absence of a healthy phase two process the liver will not process fats as designed, leading to weight gain. So eat your broccoli.
On the other hand, some scientists believe that excited neurotransmitters in the brain – sometimes ignited by thoughts of pleasurable things – like doughnuts – result in hightened metabolic response and attendant weight loss.
Hmmm.
OK, the first paragraph is absolutely true, the second made up out of whole cloth. But you decide which theory you want to tell your wife next Saturday when you are out running errands with the kids……..
Note, too, that such a tax would be regressive.
As I noted when the subject came up last week, BMI, as it’s being used here, is junk science.
One more point: there’s a significant body of science suggesting that for as long as we’ve been a species we have preferentially sought out the highest fat food source in our environment. That doesn’t mean that it’s healthful to do so but it does suggest that the predisposition will not be easily overcome.
You picked the wrong veggie for me. If you had said almost any other, I’d have taken that over the donuts any day. And I’m overweight, anyways. Go figure.
I love donuts, but can’t stand Krispy Kreme…so the broccoli.
This is a reprise of a sixties book. Ezra Klein can’t get past that?
The book, the book, Michael Harris on obesity in America? Circa 1962?
I can imagine in a hunter-gathering type situation this would be a good strategy. Now that we don’t live in such societies and have mastered farming grains in large quantities this previously winning evolutionary strategy might become one that isn’t so winning.
Krispy Creme is too sugary. Makes my teeth sharp, Mr. Verdon.
Now Jerry’s down the highway…
Yep, too sugary, couldn’t agree more. Now, the chocolate and maple bars at Manna donuts down the road….
Interesting, so how much of the “obesity epidemic” is merely due to demographic shifts?
But what’s the damn book? It’s been in sociology classes for years.
Michael Harrington The Other America.
Michael Harrington
BTW Michael Harrington went to my high school.
So what do you think of Michael Harrington?
I think one interesting thing is that over the last 20 years (or so), we’ve ratcheted up exercise suggestions: From “20 minutes, three times a week” to, well, I hear some say “an hour, most days.”
I’d think that has to coincide with a decline in the natural work we all do. Fewer “muscle” jobs, more “greeters”. Fewer walkers and bike riders, more suburban drivers.
(You probably only need to walk 2 miles to Krispy Kreme to make a donut or two ok.)
… off to finish the conversation with the dumbbells.
I blame the demise of the workout montage in the movies. Without girls in leotards and leg warmers, how can we be inspired to exercise?
“Interesting, so how much of the “obesity epidemic” is merely due to demographic shifts?”
Mine wasn’t a snark hit and run observation. I’m dead – uh, maybe a better phrase here, “very” – serious here.
Not impressed by all the overweight NBA players (average BMI something like 27), and obese NHL players (average BMI close to 30)?
Waist to hip ratio seems to be a much better predictor of health …
Why are my only choices broccoli and donuts? Donuts, of course! Throw in options of blueberries or asparagus, and it gets a little more even-handed.
But broccoli and donuts? Cripes, whose idea was it to classify broccoli as a food anyway? Yuck.
hln