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Obesity Stigmatization

A couple weeks, I engaged in a little kerfuffle over the role of personal responsibility in diet and health.

There I wrote:

But, didn't Moss just spend the preceding ~300 pages trying to convince us that our food choices are out of our control - that we are "hooked" - and that we are little match for the teams of scientists and advertisers employed by Big Food?  The implicit implication seems to be that consumers need a more powerful third party - the government - to constrain Big Food - because these are matters beyond our control.  

That's a story of helplessness - of victimization.  And whether they mean it nor not, narratives such as this can be demotivating.

To advocate people take personal responsibility for their food choices - as I have - is a message of empowerment.

Parke is right that some of the "food police" also encourage (and practice) personal responsibility, but I contend that much of their writing and their policy advocacy undermines their own message.

Today, I ran across an article in the Journal of Experimental Social Psychology  that provides empirical evidence related to the phenomenon I mentioned.  The abstract:

America's war on obesity has intensified stigmatization of overweight and obese individuals. This experiment tested the prediction that exposure to weight-stigmatizing messages threatens the social identity of individuals who perceive themselves as overweight, depleting executive resources necessary for exercising self-control when presented with high calorie food. Women were randomly assigned to read a news article about stigma faced by overweight individuals in the job market or a control article. Exposure to weight-stigmatizing news articles caused self-perceived overweight women, but not women who did not perceive themselves as overweight, to consume more calories and feel less capable of controlling their eating than exposure to non-stigmatizing articles. Weight-stigmatizing articles also increased concerns about being a target of stigma among both self-perceived overweight and non-overweight women. Findings suggest that social messages targeted at combating obesity may have paradoxical and undesired effects.

Fat Taxes

Two recent students on "fat taxes" have emerged in the economics sphere.

Here is the abstract of a paper by Chen Zen and colleagues in the American Journal of Agricultural Economics

A censored Exact Affine Stone Index incomplete demand system is estimated for 23 packaged foods and beverages and a numéraire good. Instrumental variables are used to control for endogenous prices. A half-cent per ounce increase in sugar-sweetened beverage prices is predicted to reduce total calories from the 23 foods and beverages but increase sodium and fat intakes as a result of product substitution. The predicted decline in calories is larger for low-income households than for high-income households, although welfare loss is also higher for low-income households. Neglecting price endogeneity or estimating a conditional demand model significantly overestimates the calorie reduction.
Here is an exerpt of an NBER working paper by Harding and Lovenheim
Our main finding is that nutrient-specific taxes have much larger effects on nutrition than do the product-specific taxes we study. However, they do not cost more in terms of consumer utility. While a 20% soda tax reduces sugar purchases by 10.35%, it only reduces overall caloric intake by 4.84%. Taxing packaged meals actually increases slightly overall caloric intake, even though this product group is the unhealthiest per serving. Taxing snacks/candy also has at most small impacts on the purchased nutritive bundle.

In contrast, taxing nutrients has large impacts on nutrition without producing larger welfare losses than product-specific taxes, largely because of the broad-based nature of these taxes. Among the three nutrient-specific taxes, sugar taxes stand out as particularly effective. A 20% sugar tax reduces sugar consumption by 16.41% while also reducing caloric intake by 18.54% and salt consumption by 9.63%. Consumer indirect utility declines by 2.6% as a result, which is very similar to the utility cost of a soda tax and SSB tax.

Two points.

First, both these studies show certain kinds of taxes can have some effect on intake (although often in less than anticipated ways). However, even the most effective taxes (in both studies) causes consumer welfare to fall - although these are rarely discussed in dollar terms.

Second, we already have something akin to a sugar tax - farm policies that include production allotments, quotas, and trade restrictions which make sugar 2 to 3 times more expensive in the US compared to the rest of the world. Of course, we also subsidize corn, which makes HFCS relatively less expensive. Here is a nice paper by John Beghin and Helen Jensen on some of the economics of sugar policies.


Mexico Passes Soda Tax

Friday the Mexican congress passed a nationwide soda and "junk food" tax.  

l've written so much on these sorts of taxes, it is hard to know what more can be said.  I suppose the best, succinct thing I can say is what I sent in a letter to the New York Times, in response to a previous story they ran about the issue:

Writing about a proposed 7.7 cent per liter soda tax in Mexico, Elisabeth Malkin cites a Mexican corner store vendor who doubts the tax will make a dent in sales.  The economic research concurs with this assessment.  Study after study has shown that soda taxes of this magnitude will have trivial effects on weight, and yet will raise revenue from many consumers who can least afford to pay.  For example, my co-authored study in the Journal of Health Economics estimates that a 10% tax on sugar-sweetened soft drinks would reduce weight by only about two tenths of a pound.  Another study from Cornell University has even found evidence of adverse unintended effects from soda taxes that arise from increased consumption of higher calorie juices or alcohol.  Denmark recently repealed their fat tax for precisely these reasons: complications arising from unintended consequences and consumer backlash. We all want people to lead healthy, fulfilling lives but we must also marry these concerns with the evidence on whether the policies being pursued will actually create the benefits we desire.

This comes on the heels of another "simulation" study was released, this one in the journal BMJ, which concludes:

A 20% tax on sugar sweetened drinks would lead to a reduction in the prevalence of obesity in the UK of 1.3% (around 180 000 people). . . . Taxation of sugar sweetened drinks is a promising population measure to target population obesity, particularly among younger adults.

I suppose the good thing about the Mexican developments is that we can finally put to test the predictions of some of these simulation models.  

 

Good news for donut lovers

I've always been a big donut fan.  But, they are obviously not the healthiest of breakfast options.  The good news from this study is that if you're willing exercise a bit, you might be able to tolerate a few of those delicious sugar-fat delicacies:

The objective of the study was to determine if exercise training can prevent the anticipated deleterious effects of a fat-sugar supplemented diet on endothelial function and blood markers of cardiovascular risk in young men. Twenty-one, healthy college-aged males were randomly assigned to either the doughnut + exercise or doughnut only groups. Both groups were fed 2 doughnuts per day, 6 days per week, for three weeks, while maintain their current diet. The exercise group completed 4 exercise training sessions per week consisting of 2 high intensity interval training bouts (up to 95% VO2peak) on a cycle ergometer and two moderate intensity, steady-state bouts (at 75% VO2peak) on a treadmill. Changes in body weight and composition, markers of endothelial function, oxidative stress, serum lipids, and blood glucose were measured in each group. As expected, cardiovascular fitness increased significantly in the doughnut-supplemented + exercise group as compared to the doughnut-supplemented (p=0.005). Significant increases in body weight (p=0.036), fat mass (p=0.013), and body fat percentage (p=0.014) were seen in the doughnut only group as compared to the doughnut + exercise group. The doughnut + exercise group showed significant improvements in fasting serum triglycerides (p=0.036), plasma insulin (p=0.039) and insulin sensitivity (HOMA; p=0.05) as compared to the doughnut only group. The doughnut + exercise group saw a significant improvement in nitric oxide availability whereas the doughnut only group experienced a significant decline (p=0.014). There were no significant changes in other markers. Despite the addition of a fat/sugar supplement of ~11,600 kcal over three weeks, 4 exercise sessions per week were sufficient to prevent a gain in body weight and fat mass, and also improve some measures of cardiometabolic risk. These results suggest that exercise may be necessary to prevent some adverse health outcomes associated with transient periods of excessive energy consumption 

 

Does Being Fat Make You Poor?

It is often asserted that obesity is associated with all kinds of bad outcomes, one of which is lower wages.  There had been several studies (such as this one) finding such a correlation.  I even mentioned the obesity-wage-penalty in The Food Police  when asking whether obesity is a private or a government matter (a wage penalty would suggest yet another personal, private reason why one would worry about their own weight).

However, a new research paper suggests the wage-penalty story may be wrong, or at at least misinterpreted.  Here's the abstract:

Women's wages and employment probabilities do not follow a linear relationship and are highest at a body weight that is far below the clinical threshold of obesity. This indicates that looks, not health, is the driving force behind the adverse labor market outcomes that overweight women are subject to. Further support is lent to this notion by the fact that wage penalties for overweight and obese women are only observable in white-collar occupations. For men, on the other hand, bigger appears to be better.

In short, heavier women in white collar jobs earn less than thin women in white collar jobs, but it is mainly a "beauty premium"  rather than an "obesity discount."  Men, apparently, can eat what they want without fear of reduced wages.