Looking Up Everywhere

Feb 16, 2012 in Uncategorized
Tags: PEER (Population Economics Environment Resources)

I made this graph below from Imperial College London’s School of Public Health national-level data on body mass index (BMI). Heavier, shorter people have higher BMIs and taller, skinnier people have lower values.

However I’m not primarily concerned with BMI itself, but rather with its year-over-year percentage change. The graph below shows the change in average BMIs of Russian men and women from 1980 through 2008.

You can see a big dip (especially for women) in early 1990s, after the collapse of the Soviet Union, bottoming out about 1994.

After 1998, there was a dramatic change. As of 2008, Russian men were gaining about 0.6% and Russian women about 0.3% BMI points per year. Historians tend to divide recent Russian history into pre-1991 and post-1991, but from a BMI perspective, it might be better to think of Russia as pre-1998 and post-1998.

What interested me about the graph above especially is how Russians were doing during the 1980s. Men were losing BMI (in reality, this likely means losing weight) in the early part of the decade and then gaining some back later in the decade, but women lost BMI consistently throughout the 1980s.

BMI strikes me as perhaps as good a measure of the economic health of a nation as any other. Gross Domestic Product (GDP), per-capita income (PCI) and purchasing power parity (PPP) can be manipulated or simply misreported, but BMI is calculated solely from rather easily and reliably measured factors. Since height does not tend to change dramatically year-to-year, BMI is essentially a measure of how well people are eating.

I would suspect that better-functioning countries tend to see increases in the BMIs of both men and women. A healthy population probably does not consistently lose weight, nor see men gain while women lose year after year. Perpetual weight loss of an entire population is not sustainable.

The collapse of the Soviet Union itself in late 1991 might have come as a surprise, but in retrospect anyone in 1987 or 1988 or 1989 who had data on the trend in Russian womens’ waistlines could see that something was seriously wrong with that country.

It made good material for Sylvester Stallone movies for the 1980s to be portrayed as the height of the Cold War, but when Reagan took office in 1981, Russian women were already losing weight and by the time Gorbachev arrived in 1985, the biggest loser in the Cold War was already decided.

Looking at data for other countries, I’m surprised to see how sensitive change in BMI seems to be to economic situations, wars and so forth. For example, for Iraq there is clearly a negative spike marking the 1991-1992 war, when both men and women started losing BMI, and then a ‘downshift’ in BMI growth following the war that started in 2003 (which did not cause people to lose BMI, but did suddenly decrease the rate at which people gained BMI). Times of war and peace are easy to see in many African countries too, especially in women’s BMI figures.

South Korean women lost BMI for about 5 years starting with the economic collapse in 1997, but women in Taiwan were unaffected by the 1997 problems and did not start losing BMI until 2001. (I later found out that in 1997 Taiwan largely escaped the troubles that hit the rest of Asia, but that it had its own recession starting in 2001.)

The BMI dataset covers all of the countries of the world from 1980 – 2008 and also it is age-adusted, so it won’t go up simply if a nation’s birth rate (and therefore, average age) increases or decreases.

The graph below shows the percentage change in BMI for men vs. women for every country as a cloud of green points. Each country makes 28 points, one for each year compared to the previous year.

In 2008, the BMI of South African women was more than 0.5% higher than in 2007 and for South African men it was more than 1% higher, the highest rate of growth for men anywhere in the world. In fact, South African men have been gaining BMI at an unusually high rate (compared to the rest of the world) for the past decade. Angola is doing so well that I have heard they have recently placed restrictions on the number of people from Portugal (their former colonizer) who can move there each year.

The points for 2008 are colored brown and a quick look shows that, overall, the world seems to be doing much better than it has on average in the past few decades. From 2007 to 2008, men did not lose BMI in any country and only in a few places did women lose BMI, with Singapore being the most extreme.

Bruce Bueno de Mesquita recently wrote a short article called ‘Looking up in Myanmar?’ But looking at the data it is clear that things are ‘looking up’ BMI-wise almost everywhere, even Cuba, Somalia, Syria, Iran and Yemen. I don’t have data after 2008, but Libya too was doing well then. The country almost at the 0%/0% point (where neither men nor women are changing BMI) is North Korea, which finally got back to zero after many years of both men and women losing BMI.

I would expect that in a perfectly equitable country, there would not be significant differences between how men and women are gaining or losing BMI. That is, the country would lie on the dark sloped line where the BMI changes are equal. Points above and the to left of the line are “male biased” – that is, men are faring better than women and points below and to the right of the line are “female biased”.

If the world was significantly biased against women or against men, perhaps most of the points would lie on one side or the other of that diagonal line.

I found this graph below comparing Sweden, the US and Afghanistan to be interesting.

The US is a prosperous and equitable country, as far as BMI is concerned. Men and women have gained BMI, on average, every year in the data and at about the same rate as each other. The US is slowly moving down the diagonal toward the point of zero growth (perhaps because we have one of the highest BMI’s in the world, meaning there’s little room for further growth.)

Sweden, on the other hand, shows a strong male bias. (Perhaps this exaplains Dr. Hans Rosling’s recent observation that Sweden is the world’s largest military weapons exporter, per capita.)

It might seem strange to think of Afghanistan as a place that is “female biased” and clearly from the data, for most of the past few decades (at least as far as BMI is concerned) Afghanistan has been a terrible place for women to live. But it has also been a terrible place for men to live, too.

All of the horrible things that Afghan men do to Afghan women they also do to other men. And it seems to show up in the BMI data. (In the Iraqi data we can see a similar effect: men there have fared worse than women in general). In just the past few years, Afghan men and Afghan women have both been gaining BMI for the first time in a couple of decades.

Here’s one last thing I learned recently, even before this month’s issue of National Geographic showed up at my door: Pay attention to Kazakhstan. They’ve been fattening up quickly since the year 2000.