Global Warming: If You're Overweight It's Your Fault!

As if people who are over their optimum weight don't have enough problems--now it turns out those extra pounds contribute to global warming.

That's what researchers Phil Edwards and Ian Roberts from the London School of Hygiene & Tropical Medicine say. They claim that overweight and obese people require more fuel to transport themselves and the food they eat, which adds to food shortages and higher energy prices. "We are all becoming heavier and it is a global responsibility," Edwards says. "Obesity is a key part of the big picture."

The Center for Disease Control and Prevention (CDC) uses a calculation involving the ratio of weight to height, called the Body Mass Index (BMI). They determine that individuals with a BMI between 25 and 29.9 are considered overweight, while someone with a BMI of 30 or greater is considered obese. (You can use this chart to determine your own BMI.)

Based on these figures, currently 400 million adults worldwide are obese. The World Health Organization (WHO) projects that by 2015, 2.3 billion adults will be overweight, and 700 million of those will be obese.

In their model, Edwards and Roberts pegged 40 percent of the global population qualifying as obese. The researchers found that obese people require 1,680 daily calories to sustain normal energy and another 1,280 calories to maintain daily activities, 18 percent more than someone with a stable BMI. Edwards believes that thinner people eat less and are more likely to walk than rely on cars, reducing the demand for fuel required for transportation and agriculture (the latter produces approximately 20 percent of greenhouse gas emissions).

According to Edwards, the next step is to identify how much a heavier population contributes to climate changes, higher fuel prices, and food shortages. "Promotion of a normal distribution of BMI would reduce the global demand for, and thus the price of, food," Edwards and Roberts claim.

I'm no scientist, but I see a few flaws in their logic. Being thin and eating less do not go hand in hand. I know several very slender people who eat a lot because of their higher metabolism. Conversely, I know a number of people who eat very little yet would probably qualify as overweight. And haven't you people heard the dietitians who claim that to kick up your metabolic rate you need to eat more?

The idea that thinner people are more likely to walk than use automobiles to transport themselves may be true in small villages and towns. In large urban areas where people live great distances from their workplaces and shopping centers, that's much less likely. Figuring in the use of public transportation might push the numbers down a little bit, but I doubt the researchers can conclude that skinny people use public transportation more than overweight people.

Finally, assuming that people eating less will drive down the demand for and cost of food only looks at part of the total equation. The law of supply and demand suggests that as the demand for an item is reduced, production of that item also decreases, especially when the cost to produce that item stays the same or increases. With a sizeable portion of our world population facing food shortages at current production levels, reducing the amount of food we produce would certainly not decrease that particular statistic, and could cause an increase in world hunger figures.

At least Roberts and Edwards don't personally contribute to this aspect of global warming. Based on their photos, it would appear each has a "normal" BMI in the 18- to 25-percent range. However, it looks like one or two of their staff might be helping to make global warming a reality. You guys might want to consider changing your hiring standards, or at the very least put these offenders on a diet.

As for me, I'm not going to worry about whether the calories I consume have helped increase the world's average temperature by less than a degree over the last 100 years. In fact, all this talk of food has made me realize I've nearly missed breakfast!