What Everyone Is Afraid to Say About Obesity
WHY YOU SHOULD CARE
Because we’re flushing billions of dollars down the drain.
Throughout most of his playing career, Shaquille O’Neal was clinically obese. Not just overweight, which is a lesser form of fat, but obese. Maybe this isn’t too surprising considering Shaq is a huge guy. But how about this: When athletes Sonny Liston and Muhammad Ali fought in 1964, both were technically overweight. And yet you don’t typically hear doctors recommending that you put on a few pounds at your annual physical.
The fact that these elite athletes would fit into demographics synonymous with poor health points out a fundamental flaw in the way medical professionals measure overweight and obesity. They use a scale called BMI, which stands for body mass index. The problem? That BMI doesn’t differentiate between fat weight and muscle weight, which means that this scale thinks a 300-pound basketball player and a 300-pound video game player are pretty much the same guy, as long as they’re roughly the same height. For example, you could be a skinny couch potato at high risk of heart disease, but your BMI will put you in a healthy category. Conversely, you could be in good health yet heavier, and the BMI scale would put you in an unhealthy category.
We’re battering a ram into a brick wall trying to measure success through people’s BMI.
So this isn’t just about semantics. It’s about the way we sculpt policy. This misunderstanding has major implications for the way public health officials understand and try to act on our collective health. We could be spending billions of dollars treating Shaqs for unhealthiness and treating “World of Warcraft” geeks like they’re just fine. Since 2009, the NIH has spent more than $3.3 billion on obesity research, most of which is really aimed at figuring out how to prevent chronic disease through increasing exercise and encouraging healthy eating. Michelle Obama’s Let’s Move campaign is a perfect example of this: Our first lady is always talking about childhood obesity, but her program asks our kids to move more and eat better. Getting people to change their habits won’t necessarily have any impact on their BMI, but it will improve their health. She could be at the helm of the most successful public health
Despite its clumsiness, the BMI scale isn’t going anywhere anytime soon. It’s just too easy to use. Pretty much anyone can find a website that will calculate their BMI from the comfort of their own home. There are a few simple alternatives to the BMI scale — none of which are terribly complicated, but all of which are just a little more difficult than a simple online calculator. We could use fat calipers, for instance, to measure body composition, but those require a trained professional to use reliably. We could measure waist circumference with a tape measure, but that would require gathering more than just the simple demographic data (height and weight) that we use for BMI, and that means higher costs; which means our own laziness and limited resources could prevent us from making use of this alternative. If public health professionals are serious about stopping our chronic disease epidemic, they are going to have to stop being distracted by obesity and start focusing on what really matters — people’s lifestyles.
And to be fair, BMI isn’t totally useless. Having a higher BMI is legitimately associated with a lot of chronic diseases, including diabetes and cardiovascular disease. For example, people in the highest possible BMI category have 20 times the risk of diabetes, and women classified as overweight are more likely to have hypertension, high cholesterol and a slew of other health problems. But the key here is that these diseases are associated with, not caused by, obesity; indeed, most of the chronic problems we blame on obesity are not caused by the weight itself, but by unhealthy habits that also make people fat. Eating too much of the wrong thing causes high cholesterol and type 2 diabetes — and it also makes you fat. Sitting around too much causes cardiovascular disease and weight gain.
If the goal of obesity research is to reduce obesity-related diseases, then the money should be spent on addressing those diseases by helping people live healthier lives. And while we are funding research to help change people’s behavior and promote better habits, we’re battering a ram into a brick wall trying to measure success through people’s BMI. Certainly, obesity itself does cause some health issues directly (like sleep apnea), but the issues it causes are not nearly as dangerous or as expensive to treat as those with which it shares a common root. We’d be better off attacking that root.
This OZY encore was originally published Nov. 23, 2014.