Lambert here: I’ve noticed the same thing in Thailand. Five years ago, obesity was almost non-existent. Now it is present, especially in children. The difference, IMNSHO, is MacDonalds, Krispy Kreme, Dunkin’ Donuts, KFC, Swansons, and replacing street food with snacks from 7/11. All, except for the last, very prestigious venues, sadly!
By Osea Giuntella, Assistant Professor of Economics, University of Pittsburgh, Matthias Rieger, Assistant Professor of Development Economics, International Institute of Social Studies, Erasmus University Rotterdam, Lorenzo Rotunno, Assistant Professor of Economics, at Aix-Marseille University. Originally published at VoxEU.
The majority of obese adults are now found in developing countries This column presents new evidence on the effects of trade on obesity in Mexico. The results indicate that across Mexican states, a one standard deviation increase in the unhealthy share of food imports from the US increases the likelihood of individuals being obese by about 5 percentage points. As developing countries around the world open up their food markets to industrialised countries, they may be accelerating their ongoing nutrition transition and imposing high future costs on their health systems.
Obesity is not the first health challenge that comes to mind when thinking about the global south. Obesity is rather associated with the Global North, particularly the US (think soda drinks, fast food, and lack of exercise). But this conventional wisdom is passé. The majority of obese adults – those with a body mass index of 30 and more – are now found in developing countries (Ng et. al 2014). The Global South is in the midst of a health and nutrition transition (Popkin and Gordon-Larsen, 2004). While communicable diseases and undernutrition are on a (slow) decline, non-communicable diseases and overnutrition are taking hold of populations, and they are doing so rapidly.
Given the known health risks (such as diabetes and cardiovascular diseases) and economic costs of obesity, what can policymakers in the Global South do to prevent obesity in epidemic proportions? Important lessons may come from countries that have already undergone this transition and from examining potential drivers that are amenable to public policy. The much-discussed case of Mexico is ideal for such an exercise.
Obesity and trade: The case of Mexico
Mexico’s obesity rates increased from 10% to 35% over the period 1980-2012 (according to our analysis sample including adult females). And among the already obese OECD countries, Mexico ranked second in 2015, surpassed only by the US (OECD 2017).
Coinciding with these profound changes in population health, Mexico has opened itself to trade in foods mostly with the US. Currently over 80% of Mexican food imports are American. In Figure 1, we show the evolution of Mexican imports of foods and beverages from the US over time. While overall food imports have increased dramatically, food that is typically considered unhealthy has surged quite spectacularly. Notably, exports of ‘food preparations’ are 23 times larger in 2012 compared to 1989.
Figure 1 Mexican imports of food and beverages from the US over time
In Figure 2, we classify Mexican imports from the US as unhealthy or healthy food using the United States Department of Agriculture (USDA) Dietary Guidelines (for instance, ‘dark green vegetables’ are recommended for increased consumption, while ‘refined flour and mixes’ are advised for reduced consumption). US exports to Mexico of both food groups have increased since the late 1980s, but unhealthy food groups at a much faster rate.
Figure 2 Unhealthy and healthy Mexican food and beverage imports from the US
Such trends naturally raise the suspicion of a possible, causal link running from greater consumption of US foods to rising obesity prevalence (e.g. Jacobs and Richtel 2017, Rogoff 2017). However, to date no paper has attempted to estimate a direct causal relationship between obesity and trade.
Estimating weight gains from trade in foods
In a new working paper, we quantify the impact of US food exports on individuals’ likelihood of being obese across Mexican states over the period 1988 to 2012 (Giuntella et al. 2017). To this end, we match several rounds of anthropometric and household expenditure surveys with product-level food trade data. Our main results are based on female adults for which data are available over this long time span.
We calculate the unhealthy share of food imports from the US by differentiating food items using the USDA Dietary Guidelines for Americans. We then allocate these aggregate food imports (healthy, unhealthy) to Mexican states. More specifically, we exploit variation in Mexican states’ historical expenditure by food products prior to trade integration. Our identification strategy assumes that aggregate trade shocks heterogeneously impact sub-national units as a function of time-invariant or ‘baseline’ variables (e.g. Dix-Carneiro and Kovak 2017, Autor et al. 2013). Note that there is substantial heterogeneity across Mexican states in obesity rates and historical food expenditure patterns, which further motivates our modelling approach.
Our empirical models also control for a host of state (such as food prices, GDP, FDI, migration) and individual covariates, as well as state fixed effects and state-specific time trends. In a second empirical strategy, we relate long-run differences in obesity rates at the state level to changes in unhealthy food imports conditional on baseline covariates. We instrument US exports of unhealthy foods to Mexico with corresponding US exports to other countries. And alternatively, we use ‘gravity residuals’ singling out the comparative advantage of the US in unhealthy food production relative to Mexico (akin to Autor et al. 2013).
Quantifying weight gains from trade in foods
We find that a one standard deviation increase in the unhealthy share of imports (equivalent to a 14 percentage point increase) raises the likelihood of obesity by about 5 percentage points. The effect amounts to 18% of the sample average in obesity. Findings using long-run difference models and IV estimates, as well as gravity residuals, are qualitatively similar – pointing to a plausibly causal effect.
Our main finding passes a series of robustness and placebo checks:
- Plausibly unrelated imports from the US (such as apparel products) do not impact obesity.
- The effects associated with food imports from the rest of the world are insignificant and small, underlining the specific importance of US foods for obesity.
- Likewise, unhealthy Mexican food exports to the US are not correlated with obesity.
- Similar patterns emerge if we employ food imports from the US for final demand.
- Overall (the sum of healthy and unhealthy) food imports do not correlate with obesity, highlighting the importance of differentiating ‘unhealthy’ and ‘healthy’ US foods.
- Our main results are robust to dropping Mexican states one by one.
- Similar patterns are obtained using body mass index (in quantile regressions) or overweight as outcome variables.
Health inequality and trade
Weight gains due to trade vary across socioeconomic groups. As illustrated in Figure 3, women with low levels of education face a greater risk of trade-induced obesity – their obesity risk is 5 percentage points higher than that of more educated women in a Mexican state with average exposure to unhealthy food imports. This differential goes up to 8 percentage points as the state’s trade exposure rises by 14 percentage points (one standard deviation). This interaction effect between education and trade is robust to the inclusion of state-time fixed effects (that is, purging the main local effect of trade exposure). The results are consistent with the well-known hypothesis that more educated individuals are more efficient producers of health investment than less educated ones. This educational gradient may be exacerbated in food environments where individuals are faced with more unhealthy food choices (Mani et al. 2013, Mullanaithan 2011, Dupas 2011).
Figure 3 Inequality between education groups in obesity risk and unhealthy food imports
Income, prices, and tastes
Having established a direct impact of US food exports on obesity prevalence in Mexico, we next turn to exploring possible mechanisms. Trade impacts incomes, prices, and tastes (due, for instance, to exposure to a foreign lifestyle and advertisement), all of which may drive the observed impacts on obesity. First, note that our main effect is robust to controlling for state GDP per capita, the total share of expenditures on unhealthy foods, as well as the relative prices of healthy versus unhealthy goods. Second, estimating demand equations over healthy and unhealthy food groups, we find that exposure to unhealthy foods from the US has redirected overall expenditure towards unhealthy foods. This observed shift is robust to controlling for real income and prices (for a similar empirical strategy, see Atkin 2013). In other words, trade with the US appears to influence tastes for relatively unhealthy foods. Increased variety of unhealthy foods boosts demand. These patterns are in line with a shift to ‘Western’ food consumption and increases in body weight among East Germans following the fall of the Berlin Wall (Dragone and Ziebarth 2017).
Policy implications
Nations have a lot to gain from trade. But weight gains and the associated health losses from trade in foods have been largely omitted from the equation. As developing countries around the world open up their food markets vis-à-vis industrialised countries – which tend to have a comparative advantage in more processed and less healthy foods – they may accelerate their ongoing nutrition transition. Obesity may put high costs on future health systems and the economies of the Global South.
Undoing the nutrition transition is likely harder than moderating it in the first place. Obesity and unhealthy food habits tend to be persistent. The Mexican experience is informative for countries in the Global South. Integrating nutrition and other health concerns into the formulation of food trade policies is paramount,[1] and such concerns should feature high up on the agenda in future trade negotiations.
Our findings suggest that differentiating between healthy and clearly unhealthy imports may help slow down secular trends in obesity around the world.
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Lambert here: I’ve noticed the same thing in Thailand. Five years ago, obesity was almost non-existent. Now it is present, especially in children. The difference, IMNSHO, is MacDonalds, Krispy Kreme, Dunkin’ Donuts, KFC, Swansons, and replacing street food with snacks from 7/11. All, except for the last, very prestigious venues, sadly!
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Agree 100% But I am of a age that I can remember when most people were thin IN THE US. My step father was considered “chunky” and in need of losing weight for his diabetes – I was looking back at old family photos, and I would say that today he would be thinner than 70 – 80% of males of his age today…maybe more. I try to remember accurately the adult males, and I can only distinctly remember my male elementary school teachers, and though they were considered perfectly normal, I think I would look upon them as being rail thin.
I can remember when gas stations sold tires, old, car batteries, and maybe, had a coke vending machine.
Now they are snack emporiums with NOTHING but high calorie food.
Actually, in addition to high calorie “food,” almost all of those gas station “convenience stores” also sell beer and wine: fill up your gas tank and get loaded, all in one quick stop.
I weigh 235 pounds now. When I quit drinking in 2003 I went exercise-crazy and got down from 205 pounds to 145 pounds.
I notice this too with the young people in the US- they are not morbidly obese (yet)- but they are carrying weight like a middle age sedentary people used to.
Back in my day, those kids would be thin, and a lot of them would be skinny. The food has changed and it has changed the morphology of the population
Don’t major free-trade agreements explicitly prohibit such health-based “differentiations” (whether regulatory or tariff-based) amongst imports?
If so, then what are the actual policy implications — the article does not in fact present any, for the consequence flies in the face of prevalent doctrine: no more untrammelled free trade…
I’d like for the study to do a breakdown of what it considers ‘healthy’ and ‘unhealthy’. Especially a breakdown of vegetables, seed oils, and processed food. I never thought I’d be a keto/paleo convert, but I am strongly starting to think that grains and starches and other high-carb crops (whole grain or no) are the big culprit behind the North American obesity crisis. Even moreso than refined sugar. HFCS gets blamed a lot, but remember that corn is a high-sugar grain.
Its very hard to get real facts through the fog of cranks, hard sell, commercial interests and dodgy science, but I think boiling it down to eating lots and lots of whatever plants and plant products are seasonal, avoid if possible anything with an ingredient list printed on the side of a box, minimise all sweetened and refined carb products, eat lots of fermented foods (but not from the cool box in a supermarket) and occasionally fast.
Although she has a very specific perspective, I find Ronda Patrick and her foundmyfitness site to be a useful source of information, she does good interviews with specialists on diet and health.
Jamie Oliver had some good advice here. He said to read the ingredients listed at the side of what you want to buy. If they sound like stuff that would be in your grandmother’s pantry, then go for it. If instead, it sounded like something from a chemist’s lab, then give it a miss.
>think that grains and starches and other high-carb crops
They may not be ideal. Yet the problem with saying the solution is to go Paleo is that those things have been around since we stopped hunter-gathering like I don’t know how many millennia ago.
Remember what “Paleo” refers to, and note that Fresno Dan above – who may not be a spring chicken, but… :) – contrasts today’s population with one that was born maybe 100years ago. Heck, I suspect that my family of that generation often only had grains. As a very, very young child, at the ancestral home, I asked my Dad whether they had fish in the little pond I had just discovered in the corner of the property. His answer?
“If we had fish we would have eaten them”.
My family was engaged in subsistence farming and fishing for generations in Maine. A family geneaology shows that in the 1700s, everyone in my father’s gene pool lived to be at least 80, some into their 90s.
Given the proximity to mills (not great) and low population density, I doubt they ate much in the way of grains then. They would have eaten vegetables and fruits in season, including corn, which would also mean mainly root vegetables in the winter (potatoes, turnips, onions, rutabagas, maybe beets, but those probably pickled), pork (one pig goes a long way), fish, eggs and the occasional chicken when it got too old to lay eggs, and dairy products (I am pretty sure there were some cows on the island). And of course game and fish.
The lifespan of his ancestors dropped in the 1800s. Not sure bread played any role, but bread would have been much more available in Maine in the 1800s than 1700s.
Life in Maine sounds like a lot like Cornwall in the 1700s and 1800s but without the extensive mining. The fare may have been simple but I think that there were major differences. The species of plants were different to what we see today and were more varied. There have been articles on the hundreds of apple varieties available back then alone. Also, this basic fare would have had an extensive recipe library to use with them. No chemicals, no hormones, now GM foods. Also, the amount of fish off the coastlines was almost beyond belief back then and was readily available.
A page at https://www.mainememory.net/sitebuilder/site/901/page/1312/print shows the shift to more grains back then but I do not know if the bread would effect the health of people though it was more packed with nutrients than modern bread. Certainly there was an effect on their teeth as the milling process introduced stone dust into it which had an abrasive effect on teeth. In fact, forensic pathologists use this fact to date skeletons to the 19th century. I suspect, but cannot prove, that the slightly lower lifespan may have been due to the effects of new industries on people’s bodies. On a farm, you can pace your work to your own limits. Working in an industry, you must pace yourself to the work – a major shift.
Corn versus flour tortilla consumption would be an interesting time-series to measure in Mexico, particularly after NAFTA and its baleful influence on Mexican corn farmers. Flour tortillas are worse than corn tortillas in terms of diabetes contribution.
I believe that is a function of the processing. Corn is usually processed as a whole grain when used as a flour, so the fiber is still present. However, most flour tortillas are made of while flour which has had the fiber removed. Whole wheat flour tortillas should be pretty good, but I believe they are done as an “unleavened bread” so are not necessarily as nutritious as a whole wheat flour sourdough or similar bread where the nutrients are easier to extract without a high glycemic index.
“In Defense of Food” with Michael Pollan is a really interesting series on Netflix.
There is some useful information about the effects of dietary changes on the Tohono O’odham, an indigenous group living in the Sonoran desert, whose diet changed from tradition foods to more processed foods beginning in the 1960s. So some evidence from a subset of people living along the Mexico/US border (itself an interesting dilemma as their history there predates any borders).
https://everipedia.org/wiki/Tohono_O%2527odham_people/
Gary Paul Nabhan has also documented the traditional dietary practices of Tohono O’odham as well as the impact of the changes.
Grains and starches were probably a bigger portion of the diet somewhere like Mexico sometime before all the trade agreements, as they have historically been a large part of the diet almost everywhere (post paleolithic). Corn is not new to Mexico just recently. Junk foods are not just high carb but both high carb and high fat generally (it is probably the whole combination in junk food not any one macro-nutrient that is the problem). Activity levels often have gone down as well (I don’t know all the details on Mexico).
. . . Even moreso than refined sugar . . .
Ever heard of Pure White and Deadly by John Yudkin?
In a similar vein, but focused on diabetics.
http://www.schwarzbeinprinciple.com/pgs/dr_schw/sp_I_intro.html
In a grocery store there are walls of slow acting poison wherever one looks. Coca Cola? Pure poison. Little Debbie snack cakes? Pure poison. It just goes on and on, making everyone sick so they can get treated by the tender mercy medical system that cares so much about you.
Junk and processed food are sold as a by-product of Agribusiness “Big Business”. A direct link of the behavior is a correlation between the use of glyphosates in the food supply around the world. Mexico unfortunately with NAFTA introduced US corn and many other food, pushing out more nutritious indigenous foods. This is the cost of corporations running world-wide food supplies, presenting easy to eat junk made only for profit.
This is a German documentary on what we as consumers should become aware.
https://www.hooktube.com/watch?v=XDyI10Z8aH0
HFCS = High fructose etc, yes yes! but why not High Fat, Corn & Sugar? Targets the key bad combination that is easy to over-eat.
haha don’t want to start an argument but This Week the news is high fat isn’t a problem. And it seems to be really, really bad to substitute “high fat” foods with some laboratory concoction, either eat them as is or get the calories from something (plants!) totally different.
I didn’t suggest that high fat is a problem. See the words “bad combination”? It’s actually fat+sugar+salt that makes the most palatable mix.
cool got it… interesting that while our erstwhile scientists (white lab coats on even whiter guys, flood pants, birth control glasses and of course color wasn’t invented yet so they all had to work in black and white) were taking things apart, their bodies were quite likely putting those things, as found in their brown bag lunch, together.
From a previous NC post, these three books have given me the foundation for a paper I am writing, with an acknowledgment to NC ;-)
Good Calories, Bad Calories, 2008, Gary Taubes
The Case Against Sugar, 2017, Gary Taubes
The Big Fat Surprise, 2014, Nina Teicholz
Basically, our “experts” have demonized dietary fat for no good reason, which has caused those calories to be replaced by carbohydrates, generally in the form of refined sugar. This has been viewed as a good thing. Not so much. Yes, insulin rises in response to plasma glucose and removes it from the circulation by causing it to be taken up by the liver and skeletal muscle. Insulin is also an anabolic hormone that leads to the storage of fat and antagonizes every other hormone that mobilizes stored fat for use as fuel. Chronic insulinemia largely causes the bad things we see on the street everyday. These consequences have been predictable, here and elsewhere, with the worldwide ethnographic data as convincing, to all but the congenitally obtuse, as the link between smoking and lung cancer. You will hear from the “experts” that a calorie is a calorie is a calorie. That is true, but only in a bomb calorimeter, not in the human body.
It seems the obvious conclusion here is that the wave of obesity is driven not be people eating more calories, but rather by people turning away from traditional diets and eating instead from the industrial food supply. Commercial prepared western foods are made with ingredients that disrupt their bodies’ ability to efficiently metabolize their food — ie liquid vegetable oils, which are full of trans-fats and are known endocrine disruptors (corn, soy, rapeseed oil, aka canola); meats from animals raised with constant dosing of antibiotics and steroids and given GMO feeds; dairy and eggs also full of chemicals, just like the meat stock; commodity plant crops that were raised with mega-doses of weedkiller (the underlying necessity in all GMO farming) — this is what makes people obese. Chemicals, excessive processing and overdosing of antibiotics. And it’s the cheapest food available anywhere — cheaper than traditional diets. First world countries can afford to spend a higher percentage of personal incomes on food, and increasingly they are …..as awareness grows of the dangers of industrial food.
Also, WHAT grains/foods–what varieties, how much hybridized? how much GMO? grown in what soil of what kind and quality? grown in what conditions/sunlight. Heck there are probably even more variables of which we are not yet aware. (E.g., magnetic fields. Not to mention other fields we don’t yet understand or measure, e.g., emotional or other energies stored that may enhance or disrupt a plant’s natural electric patterns.)
Various samples of “corn” or “wheat” or “potatoes” could thus each be really different (wonderful or terrible) depending on these multitude of things.
Re: “Weight Gains from Trade in Foods: Evidence from Mexico“
Michael Pollan does a very good exam of this phenomena in his book ‘In Defense of Food’. Apparently the stew of chemicals now found in the industrial food chain eventually does very bad things to human bodies.
Also, I am old enough to remember the fifties and sixties when gross obesity was extremely rare. Today, when I visit the local Walmart, every third person I see is morbidly obese.
Pollan’s wife wrote a practical cookbook that shows how to eat well and avoid much of the chemical stew.
The Pollan Family Cookbook
To fix obesity, ban food advertising
It’s not the food, its the quantity and availability. Quantity is driven by continual advertising, with the intent to creates the continual reminder to “snack” on things.
When food was food (meat and veg) and not product, people were thin. With advertising there is the constant reminder to eat. What’s advertised in not meat and veg, is it cheap-to-produce product, very profitable product.
Advertising is successful in changing behavior, if it were not the major advertisers would not continue the advertising costs.
Junk food is like Cigarettes – a combination of greed and sociopathic behavior for profit.
To fix obesity, ban food advertising.
I live in Mexico. When I go into a grocery store or neighborhood tienda, it’s packed with prepared foods, much of it junk, from the US as well as Mexican imitators. The quantity of soft drinks that people consume is staggering.
Fortunately, most cities and towns also have traditional mercados with local produce, meat, beans and grains in bulk, eggs, herbs, fresh hand made tortillas and gorditas (nothing like Taco Bell, believe me), fresh fruit juices and much more, and these places are where I do most of my shopping. I know precisely what I’m buying because I can talk to the people who grow/make it.
There also are small specialty shops: carnecerias where meat is cut to order like in an old fashioned butcher shop, panaderias, tortillerias, pescaterias, and on and on. The quality of the food in these places is vastly superior to anything I saw in my decades of living all over the US and none of it is packaged in styrofoam or plastic wrap.
Unfortunately, tho’, many Mexicans have gotten into the “one stop shopping” supermarket habit. But there is a “slow food” as well as a “decolonize your diet” movement here that I hope will gain some traction because the prevalence of diabetes is alarming.
This “slow food” and “decolonize your diet” movement in Mexico is probably taking place among the cool, hip and groovy sector of society. It will be mocked for that reason if it threatens to take market-share-drivingly significant hold. But it would be a good start at de-polluting and de-crapifying the emerging neoMexican diet.
If it spreads widely enough among the middle classes and above, perhaps the crap-adopting working classes and lower classes might get jealous and start demanding food again for themselves as well. They might even agitate for a movement to withdraw Mexico from NAFTA so Mexico can re-protectionize its agriculture and re-establish its own food-growing communities back to pre-NAFTA levels.
Love to have more ethnic delicatessens, like the jewish and polish ones that were not uncommon. I have a great persian deli that I buy my feta from, cut from a big slab
The same thing has happened in Inuit and Cree communities in the Canadian north. Abandonment of traditional diets and adoption of western whitebread diets has resulted in an epidemic of obesity and diabetes.
ORGANIC food is the answer. Spend a bit more and live healthier.
Not organic cookies though. Traditional foods, mostly fresh plants….organic as possible
Don’t knock 7-11. I’d rather eat a 7-11 in Asia than McDonalds, Krispy Kreme, Dunkin’ Donuts, KFC, etc.
Southeast Asia maybe a different situation, but the 7-11s in Taiwan, Japan and Hong Kong are really something. Transplant them to Brooklyn, and you’d have a hipster, gourmet convenience store.