Rarely does a graphic appear to depict a correlation between a country’s tendency toward biking and its obesity levels as clearly as this one, which was created by Sustrans, a nonprofit in the U.K. that supports sustainable transportation. The group has assembled a wide variety of statistics and figures about physical activity (or inactivity, as the case may be) and the deleterious health effects in Great Britain, and draws an effective comparison with other Western European nations. Other graphs have illustrated the link between the amount of walking and bike commuting a country’s population does and its obesity levels. And while this graph could benefit from the addition of a few more countries, it does indicate a correlation between overweight children and a Western European society’s propensity for biking.
This entire body of statistics and graphs can’t drive home hard enough the relationship between a nation’s transportation habits and the health of its residents. Sure, we can attribute the obesity epidemic to factors from genetics to diet changes — but it’s likely that many of those would be counteracted or rendered irrelevant with the introduction of a more active daily lifestyle, starting with our commute to work or school. (And for comparison, the percent of overweight American children has risen to 25% of the under-19 population.) [SButtonZ button="digg"]
Hat tip: Quickrelease.tv and StreetsBlog
I find this graphic to be extremely frustrating. Yeah, it looks good but where are the numbers for the other countries and what exactly is the graphic measuring anyway?
You should add Japan to the graph. Those kids must be biking like crazy over there.
Rarely do I see a graph that makes an important point so badly. This graph is an embarrassment. I second Aaron’s points. With just a few countries, how can you have any confidence that cycling is the critical factor? Furthermore, the point seems to be that increasing cycling would decrease obesity. That’s a plausible premise. But, do trends in these countries support that premise?
I don’t find the narrative’s airy assertions that other factors can confidently be assumed to be “counteracted or rendered irrelevant” by increased cycling rates. The fact is, this graph approaches a critical public health issue with a poverty of data and a dearth of analysis. Shame on you, SusTrans and Melissa Lafsky.
As a student of statistics and math, this “graph” pains me. It’s deceptive and can’t tell a single narrative. Must. resist. urge. to. punch. computer. screen.
Wow.
- 5 cherry-picked data points
- a false implication that correlation==causation
- outdated data
- unclear units on both axes
I can’t think of any more ways that this chart could be bogus!
Yeah, East Asia’s going to be an exception – more or less. The problem is that the OECD numbers define obesity as “having a reported BMI of 30 or more,” except in the US, where they define it as “having a measured BMI of 30 or more.” (Use self-reports in the US like in the rest of the world, and American obesity turns out to be the same as Britain’s, slightly less than Mexico’s, and slightly more than Canada’s. So much for “fattest nation in the world.”)
Now, the problem with using BMI is that different people have different body types. Asians have higher body fat percentage than whites for a given BMI; in effect, Asians need to be much fatter than whites by medically relevant measures to have a BMI of 30. This creates an underestimate of Asian obesity. Similarly, old people have relatively little muscle mass, so they, too, need to be much fatter than younger people to have an above-30 BMI. (This is especially bad in Japan, which is the oldest nation in the world.)
A better chart is the relational growth of obesity in children with the rise in products containing corn syrup as a sweetener. Comparing those charts to the growth of obesity in children gives a 1 to 1 relation whereas biking is only distantly related to childhood obesity. Biking will help but getting people to eat health is the answer.