Saturday, February 06, 2010

Cold and Fat

Cold places tend to have fatty cuisines. The usual explanation for this, although I know of no rigorous test, is that cold weather requires us to burn lots of energy to stay warm, and our bodies respond to this greater demand by causing us to eat more rich foods.

This simple idea has several profound implications that I will now proceed to invent.

The first implication is that " burn lots of energy to stay warm" means something very similar to "increase metabolic rate." So people in colder environments should have higher metabolisms. This matches with the current experience of myself and my wife. For the past months the temperature outside our apartment has rarely gotten above freezing, the wind is always blowing and it is generally damp. Our apartment is somewhat difficult to heat, so it is generally cool and sometimes downright cold inside. We have been eating a very rich diet, and rather than gaining weight, I think we are both loosing a bit. And although the short days cause a degree of lethargy, I have been generally quite productive, with fewer problems of concentration than usual.

There is good reason to think, in fact, that colder climates lead to greater productivity. Colder countries are systematically more economically productive than hotter countries, air conditioning raises productivity considerably, and hot countries experience more economic growth in cool years than in warm ones. My preferred speculation is that this is because the experience of coolth induces greater physiological throughput, allowing for greater activity. If one needs to expend energy to keep oneself warm, why not put that energy to some good use, such as thinking, building, or working. Why shiver when I can use the same energy sharpening the knives or generating a hypothesis?

Allow me one further observation and conjecture. Germans, who eat very heavy diets but on the average are less heavy than Americans, are in the habit of opening all the windows whenever it gets warm inside, even if it is below freezing out. Two apparently unrelated stereo-types of modern Americans, both of which have some basis in fact, may in fact be causally related. These are, we are very fat, and we keep our houses very warm in the winter. Perhaps the miracle diet so many have been searching for should include turning down the thermostat. If we burn more calories when we experience cold, and we want to burn more calories, perhaps we should experience more cold.


jte said...

On the other hand, there's the stereotype of the American home or workplace in the summer being air-conditioned so thoroughly that people have to wear sweaters indoors. Are Americans more productive in the summer when their workplaces are kept artificially cold than in the winter when their workplaces are kept artificially hot?

I'd never heard that hot climate countries have greater productivity in cool years. Could that be related to agricultural yield? Perhaps cool years are years with more rain and therefore better harvests regardless of the energy level of the people.

For sure, if you want to burn more calories it helps to be colder but it's probably very easy to eat above and beyond that incremental need. I wouldn't be surprised if part of your experience has to do with being in a place where you don't speak the language, thus inducing your brains to be working harder (even if unconsciously) to process social cues and stuff. I saw a talk on YouTube the other day that included the trivia that a world-class chess player can burn 7,000 calories in a day just sitting motionless playing the mental game. Maybe you are doing your own version of that, processing so much in your brain that you are burning an extra 1,000 or so calories a day.

Aren't Italians and Spaniards also, on average, thinner than Americans even though they live in warmer-than-the-American-average temps? Morrocans and Australians too, right? So I'm not so sure about this hypothesis.

Fern said...

There are many different climatic zones in the US though. So you would have to break states up according to the coolth factor.

According to the OECD (counting the % of people with BMI over 30) the US, Mexico, the UK, Slovakia, Greece, Australia, New Zealand, Hungary, Luxembourg, and the Czech Republic are the top ten for the highest % of obese people.