About William Masters

Professor of Food Policy Friedman School of Nutrition, Tufts University

Least-cost breakfasts?

Nathanaël Witschi Picard, 6 years old

A six year old’s weekday breakfast in Paris

The least-cost diet exercise we just did in class is beautifully illustrated by the gorgeous NYT magazine article about kids’ breakfasts around the world [h/t to Amelia].

Amazing photos.  Who knew that breakfasts could be so colorful and varied?  And seeing all these examples side by side reveals a lot about food choice.

Clearly, price and income does matter, but so does tradition and the personality of each individual child and their family.

One big influence on food choice that’s nicely illustrated by these examples is the difference between weekend and weekday breakfasts.  The weekday breakfasts are really rushed, more like least-time meals than least-cost.

Doga Gunce Gursoy, 8 years old

An eight-year old’s weekend feast in Istanbul

It turns out that meals are so much better when we have more time to prepare and eat them. Once people reach a high enough level of income to afford the nutrients we need, time allocation becomes as important as cash expenditure — and that tradeoff is especially visible at breakfast.

A lot of economists these days are very interested in how nutrition is influenced by our time use, with research on issues such as how mothers’ employment influences childhood obesity in the US, contributing to a global trend towards time-scarcity.

One of the biggest challenges in food policy is how to make food that not only nutritious, but also quick and convenient.  Any ideas?

Food values: Fresh and local! Exotic and convenient!

On the T this week, just before the start of new school year studying food choices, I just loved seeing these two ads next to each other:

From Drop Box

Our food system offers many wonderful contrasts like this: sometimes we can spend a leisurely Sunday exploring fresh, traditional and local food — but sometimes we want a jolt of fast, new caffeinated drinks from far away. My own fridge is full of such contradictions. Care to guess what opposites might lurk in there?

Thinking like an economist… about grocery stores

One good opportunity to improve public health is in grocery stores, as psychologists and economists work together to help retailers increase sales of, well…  groceries.

Today’s New York Times has a terrific news story about this frontier of research by their reporter Michael Moss.  Moss just released a lively new book about how food manufacturers raise the levels of salt, sugar, fat and other ingredients in processed foods far beyond what you’d add in your own kitchen, while research at Tufts and elsewhere has shown similar problems in restaurant food.  In contrast, grocery stores sell a lot of fruits, vegetables and other relatively healthy stuff,  generally around the perimeter of the store.  So, in the choice between processed foods, restaurant foods, and plain old groceries, what determines how consumers’ spend their hard-earned money?

Advertising.  Taste and convenience are also important, as is factual information about nutrition and health.  But those things are often hard to change, in which case advertising can provide the swing vote that nudges consumers towards what they actually buy.  The effectiveness of advertising helps explain why we see so much of it.

The research featured in today’s NYT is about a great new display ad being tested in grocery store shopping carts:  a mirror, reflecting the shopper’s face back at them.  The researchers’ hypothesis is that commercial ads distract people from their own desires, so that a mirror reminding consumers of who they really are would nudge them back towards choices they are less likely to regret later when they leave the store.

What do you think?  Where might a mirror help you make more optimal choices?

And to continue thinking like an economist, consider the problem from the store’s point of view:  in your experience, when do they try to sell you things you might later regret, as opposed to helping you find things that actually fit the long-term you?


Thinking like an economist… about pregnancy

I like to listen to podcasts when I run, mostly fun stuff from Slate and the BBC, also stories (both true and fictional)  and sometimes great lectures.  If you already listen to podcasts, or might want to get started, here’s a great one offering 20 minutes of econotainment to ease your commute or whatever: Planet Money’s Episode 481: The Economist’s Guide To Drinking While Pregnant.

Our week 1 exercise asks students to describe an instance of thinking like an economist — that is, trying to explain individuals’ choices as if each is doing the best they can under their circumstances, and then interacting with others towards a potentially predictable result. Looking at social life as an equilibrium among optimizers cannot explain everything, but it can be useful and also a lot of fun.

The Planet Money podcast interviews Emily Oster, a famous economist (meaning, famous among economists) who’s written a new book on choices in pregnancy.  It turns out that most people don’t think like economists at all when they decide what to eat or do during pregnancy.  For example, when people are optimizing, we think at the margin about incremental changes — should I drink one sip of wine?  how about a half glass?  or a whole glass?  But when people are pregnant, the rules tend to be absolute:  no wine!

Emily Oster’s great story is about that kind of paradox.  It turns out, that real people don’t actually optimize all the time — the calculations and subtleties would make our heads explode.  So we construct simple rules that clearly are not themselves optimal, but might be a predictable equilibrium among optimizing people — doctors who need to tell lots of people the same thing, and prospective parents who have better things to think about than relative risk ratios and complicated probabilities.  When we become aware of that we can perhaps overcome some of those limitations, and make arrangements to reach a much better equilibrium.

In other words, actually thinking like an economist is pretty weird…  but do you find it useful?  fun?  Listen and let us know how you see Plant Money’s great podcast on The Economist’s Guide To Drinking While Pregnant!


Wow… the class opens for previewing tomorrow.  Official first day will be September 3rd, but if you’re as keen to start as I am, you can check out the welcome videos and course details our new Trunk site!

I look forward to working with our students there — and if you’re here as a tourist checking out the blog, come back soon for their posts as the semester progresses.