What do school children want to eat?

In the past I have, at times, been somewhat critical of the National School Lunch Program (NSLP) guidelines destined to make school lunches healthier by reducing calories, sodium content, saturated fat, etc.  It's not not that I'm against healthy kids!  Rather, I bristled at the idea of a bunch of nutritionists, policy makers, etc. setting rules and guidelines for how they think kids should eat without considering how the children would respond to the rules.  Nutritional content is but one of the components we care about when eating - don't we also care about how the food tastes, how much it costs, whether it leaves feeling full, whether it is safe to eat, etc. etc.  In short, the guidelines were established with limited understanding of what children want to eat, and as such we knew very little about whether the rules might increase food waste, increase the frequency of home lunches, cause unintended substitution patterns, and so on.  

In an interesting paper in the most recent edition of the American Journal of Agricultural Economics, a team of six researchers sought to do what should have been done prior to implementing nutritional guidelines.  In particular, the authors studied almost 280,000 school lunch choices of about 5,500 elementary age children in a suburban South Carolina school district.  The authors know the precise foods available at each lunch offering, the nutritional characteristics of the foods, which foods the child selected (or whether the child brought a lunch from home - note that lunch menus were published well in advance), and some of the characteristics of the child who made the choice such as their grade, gender, race, and whether they received free or reduced price lunch.

The authors are able to take all this data to estimate demand curves associated with different food offerings.  Their demand models let them answer questions like the following:

• If the sodium content of a pizza offering were lowered, how would that change the number of children who select it?  
• If a low fat pizza is paired with a peanut butter sandwich, which would most people choose?
• If the caloric content were unilaterally lowered on all offerings, how many more children would bring their lunches from home?       

Here's what the authors find:

“If the protein content of Entrée 1 is increased by 3.2grams (one standard deviation of all entree offerings over the course of study), students are, on average, 2.8 percentage points more likely to select that offering. Increasing the fat content of Entrée 1 by one standard deviation (3.9grams) has a similar effect, though smaller in magnitude; students are only 0.2 percentage points more likely to select Entrée 1 because of this increase in its fat content. Increasing the carbohydrate content has the opposite effect; the average probability of choosing Entrée 1 over the alternatives decreases by 3 percentage points if the carbohydrate content increased by 6.8grams (one standard deviation). Thus, the first row of table 3 reveals that students prefer more fat and protein but dislike additional carbohydrates. While the results for sodium are positive, the effect is not statistically significant.”

There are important differences across children:

“While an increase in the fat content of Entrée 1 increases the average probability that a student receiving free lunch will select it, the same increase in fat reduces the likelihood a student who pays full-price will select Entrée 1. The results also suggest that students who pay full-price are more likely to select offerings with more protein than students receiving free or reduced-price lunches (Bonferroni p-value <0.0001), and those who received free lunches are more likely to reject entrées with additional sodium relative to students who pay full-price or students who received reduced-price lunches (Bonferroni p-value =0.0044).”

The authors use their results to suggest how "schools can increase the healthfulness of their students’ meals by replacing unhealthy options with relatively healthy options that are already popular amongst the students."  One things the authors didn't do (but which is possible given their estimates) is to ask: are the children better or worse off (at least as measured by their own preferences revealed by their short run choice behavior) with the new nutritional standards?  Which types of children are now happier or sadder?  Because there is no price variation in the dataset, the authors can't provide a monetary measure of the loss (or gain) in student happiness, but they could covert it to some other unit they measure - such as grams of protein or calories.  

Nonetheless, this is a really interesting study, and it has a number of important findings.  Here's some from the conclusions:

“Nationwide between school year 2010–11 and 2012–13, the number of students receiving free lunches increased while the number of students purchasing full-price lunches decreased, leading to an overall reduction in participation by 3.7% (Government Accounting Office 2014). The results of our analyses suggest that the underlying preferences for offerings with higher levels of fat and lower levels of carbohydrates may be driving the decline in NSLP participation. Full-price participants are most likely to respond to changes in the nutritional content of the offered entrées by opting out of purchasing a school lunch altogether. Our findings have particularly important implications for the NSLP’s stated goal of reducing childhood obesity as they indicate that children are likely to reject those entrées that are most compatible with this particular aim. However, our results do suggest that the future guidelines reducing sodium levels may not trigger additional participation declines.”

Food and Ag Related Election Results

Donald Trumps surprising electoral win is likely to dominate the headlines for weeks.  But, across the nation there were a variety of less-well-publicized votes on issues related to food and agriculture.  Here are a few of those results. 

Massachusetts Ballot Question 3 appears to have passed with a whopping 78% of the vote.  This state ballot initiative bans farmers from producing eggs from hens in so-called battery cage systems and it bars grocery stores from selling eggs from such systems.  Here are results from my research papers on the effects of this type of regulation in California. 

Oklahoma State Question 777 appears to have failed garnering only about 40% of the vote.  This was a so-called "right to farm" amendment to the state constitution (details here).  Also in Oklahoma, state question 792 passed, allowing (among other things) grocery stores to sell wine and liquor stores to sell cold beer.

Soda taxes appear to have passed in San Francisco and Oakland with roughly 60% of the vote and also appears to have passed in Boulder, CO with about 55% voting in favor.   These cities now join Berkeley, Chicago, and Philadelphia in instituting soda taxes on the premise that they will fight obesity.

Marijuana legalization was on the ballot in several states, While perhaps not considered an agricultural issue, somebody has to grow the stuff!  A majority of California, Nevada, and Massachusetts citizens voted in favor of legalizing recreational marijuana use, but the issue failed to garner majority support in Arizona.   

New Research on the Berkeley Soda Tax

You may remember the discussion surrounding a research paper released back in August that used interviews and survey data to suggest that the tax on sodas that went into place in Berkeley caused a significant reduction in soda consumption.  

As several other locales are considering new soda taxes in the upcoming election season, this sort of research is valuable in trying to sort out the potential effects of the policies.  

Now there is new research by Scott Kaplan, Rebecca Taylor, and Sofia Villas-Boas at UC Berkely.  The authors utilize a dataset on retail sales of various drinks in dining locations at "a large university" - presumably Berkeley.  Importantly, the authors do not actually look at the effect of the implementation of the tax, but rather they look at what happened to soda sales because of the publicity and information surrounding the vote.  That is, they look at soda sales surrounding the time of the vote but before the tax actually went into place.

Here is a figure from the paper summarizing the main findings: 

The authors write:

“We find a 30% drop in soda sales relative to other product groups during the post-election
period. In a related and contemporaneous study using survey data, Falbe et al. (2016) find
an average 21% drop in SSB quantity sold. However, because the surveys were completed
only before the election and after the tax implementation, Falbe et al. (2016) are unable to
distinguish whether this effect was from the campaign and election or from the tax itself.
Our results show that soda sales fell on-campus after the soda tax election yet before prices
changed due to the tax. This suggests that comparing pre-campaign to post-implementation
consumption may confound a tax effect with an information effect. This has important
implications for external validity. If the Berkeley SSB tax is replicated elsewhere without
a proceeding campaign war and affirmative election outcome, its effects on consumption
may differ substantially. In other words, given the amount of money spent in the Berkeley
campaign on each side of the battle, it is important to understand how much behavioral
change was due to the election and how much was due to the tax itself.”

My take on the results is that these soda tax policies may well have sizable "signaling" or "information" effects aside from whatever pecuniary effects exist.  I have found similar results related to animal welfare regulations: that the publicity surrounding a vote has a significant impact on what people buy aside from whatever impacts the policy actually has on the price or foods offered.  In short: information dissemination campaigns may be as important or more important than taxes or bans on products.  In my assessment, information policies are often far more justifiable than are more coercive policies that restrict choice. 

It will be interesting to see as future research emerges whether and how the actual implementation of the tax changes soda consumption and how long lasting are these information effects.  

More on soda taxes

A few days ago, the World Health Organization (WHO) came out with report, suggesting the use of food taxes and subsidies to encourage healthy eating.  They were particularly in favor of soda taxes.  Soda taxes seems to be picking up steam in the U.S..  After passage in Berkeley, they will now be on the ballot in several locales in coming weeks.  

I've written so much on these topics, it's hard to know what more to say.  So, I thought I'd just, for the record, tell you what I had to say on a recent Food Sommelier podcast when the host asked me about this topic (and revealed her support for soda taxes, which came about in part because she said she felt guilty for having worked for PepsiCo earlier in her career).  

I'm in episode 38 and the discussion on soda taxes starts at about the 20 minute mark.  Here is my lightly edited discussion on the issue. 

“I’m not a fan of soda taxes for a whole host of reasons . . . but let me first say, though, that it’s really not that big a deal.  And that’s probably one of the reasons I’m against it . . .  As much as I’ve written about it, you’d think I’d get my feathers ruffled a lot [over things like the Philadelphia soda tax], but I don’t have a dog in the fight really one way or the other.  It’s not a big deal in the sense that, number 1, it’s just not going to have much of an effect on obesity rates if you look at the best available research.  We are talking about taxes that will have very, very small effects on people’s weight, and there a lot of reasons for that.  

There are substitutes for sugar sweetened beverages.  People can switch to juices or even non-beverage alternatives that may have calories in them.  I’ve seen a number of studies that suggest that.  Just because we put a tax on something doesn’t mean people are not going to consume calories; they might instead switch to something else equally caloric.  . . . 

We have these intuitions . . . and little thumb rules like for every 3,500 kcal we cut out, we lose a pound.  The reality is that relationship is not linear at all.  It’s nonlinear . . .  When we’re thinking in a linear way, each calorie I cut out will cause a constant reduction in weight, but it doesn’t really happen that way.  There are diminishing returns.  You may lose a little bit initially but then it will really level off.  . . .

When you look at the burden of the tax, and this is really true of almost any food tax, its going to tend to be borne relatively (at least relative to income) more by people in the lower economic strata of society.  The reason for that is that if you look at the share of spending on food, it tends to go down as we make more money.  What that means is that poor people are spending a larger proportion of their income on food. So, anything we do to make food more expensive, that burden or that tax, is going to tend to fall more heavily on lower income populations. . . .

I’ve got a paper actually coming out . . . where we compare very low income to regular income consumers.  What we tended to find there is that is that, especially in the case of subsidizing healthy foods, the richer consumers benefit the most because they’re already, first of all, consuming relatively health foods.  And, because we found . . . that the poor tended to want to stick to their original diets. They were more habit prone, so they didn’t change quite as much either when it was a tax . . . or a subsidy trying to get them to eat something a little healthier.  

I would say lastly, I’m going to bring up this sort of elitism. . . . This sort of paternalism argument.  We feel like we know how other people should be eating.  . . . I think it’s really hard to put ourselves in the shoes of other people, and so for us to take a step back and say ‘you should be doing something different; you should be eating more like me’ presumes that we know what it’s like to have their life and have their kind of income and know all the other sorts of things they’re facing. . . .  I have a problem philosophically with that. . . .

And I do think it’s different than . . . cigarette taxes.  With cigarette taxes there really was this externality – the second hand smoke.  When you’re smoking, that really does have an effect on the people around you.  With the drinking of soda, it’s really less clear there’s that same kind of phenomenon at play.  Most of what’s happening here is some kind of redistribution within our healthcare system because of Medicare and Medicaid.  But, that’s much more complicated than most people realize.  Most of what’s happening here are subsidies flowing from relatively wealthy people to relatively poor people because relatively wealthy people pay more in taxes. . . . It’s not a popular solution but part of the argument is that if people know their health care expenses are going to be taken care of, they’re going to eat in an unhealthy way . . . Economists call that a moral hazard.  The answer for a moral hazard is that people need to have some skin in the game.  We need people to pay a little bit of the costs of their health care.  It doesn’t have to be the same for everybody, and maybe it’s just a small amount for people who don’t have much income, but I think if the concern is that if people are going to behave “irresponsibly”, there needs to be a bit of a price for that in terms of their health care costs.  But, of course, there is a real price for being obese.  That’s something we tend to forget – that there is a lot of social shame associated with being obese, wages can be lower especially for women, and there are all the attendant medical costs, some of which are shielded from the consumer because of our health care system but a lot of those are borne directly.  There is a real cost to being overweight and obese, and people bear a lot of that just through their own daily lives.  

I’m running on here, but one last point that is really important because I hear so many people get this wrong.  What they say is, ‘well our farm policy system subsidizes food and makes sugar cheaper.’  That is absolutely false.  I’m not a fan of farm subsidies, but that particular argument is false for two reasons.  One is that if you look at cane sugar.  Cane sugar has a set of really convoluted policies, but they essentially restrict supply. . . . What [sugar producers via policy] are able to do is keep out foreign competition and keep other producers from growing sugar cane.  . . . World sugar prices are much higher than they would be if we didn’t have our US cane sugar policies.  The other thing is high fructose corn syrup (HFCS).  Right now roughly 40% of our corn supply goes to ethanol.  Ten years ago, that was mostly going to livestock and food processing. . . .  It’s not exactly a farm policy, but the energy policies we’ve had over the past 10-20 years have dramatically shifted corn production from going to places like HFCS to instead ethanol production and our cars, and as a result has made HFCS more expensive than it would be otherwise.  

Should we tax sugar?  In some ways, we already do, it’s just not very transparent that we’re doing it."                                       

Evaluating the Policy Proposals of the Food Movement

That is the title of a paper I presented a few months ago at a conference put on by the American Enterprise Institute.  

The paper is a critical evaluation of the food policy proposals put forth by by Mark Bittman, Michael Pollan, Ricardo Salvador, and Olivier De Schutterand (see here, here, and here).  As I argue in the paper, these policy proposals have largely escaped serious criticism, but it is important to take a closer look for the following reasons.

“While members of the so-called food movement have historically had much less influence on farm and food policy than, for example, farm commodity organizations, recent events suggest that power dynamic could be changing. Food movement members have been extraordinarily adept in fomenting the modern day food and farm zeitgeist, selling numerous bestselling books and garnering space in influential media outlets. For example, in 2015 the New York Times hosted a “Food for Tomorrow” conference which focused on food and farm policy issues that are centerpieces of the food movement agenda. First Lady Michelle Obama made food policy a signature issue by planting a White House garden, retooling school lunches, and including the White House chef as a policy advisor. The emergence of the local food and farm-to-table movements, as well as state ballot initiatives on labeling of genetically modified food and farm animal housing, can also be seen as outgrowths of the impacts of the food movement.”

The authors first start by painting a dire picture of the state of food and agriculture.  Then they offer a set of "guiding" principles before putting forth more than 20 specific policy proposals.  In the paper, I go point by point and address each one.  Here I'll just offer my summary:

“I demonstrate that the authors offer no consistent, underlying philosophical basis for when the federal government should (and should not) intervene and offer no framework for making tradeoffs when proposed “guarantees” come into conflict. Moreover, the authors misjudge the trajectory and impacts of changes in food and agriculture and thus overstate the urgency and scope for intervention. The authors’ numerous specific policy proposals tend to represent a hodge-podge of ideas that have already been tried, are already being undertaken by the USDA, or fail to hold up under close scrutiny, although there is some common ground on a few proposals. ”

In a particularly telling example, where the authors propose funding for all sorts of youth activities to promoting cooking and agriculture, they make no mention of the largest food and agricultural youth organizations already working in schools across the country: 4-H and FFA.