This month, the Journal of American Medical Association (JAMA) published a study done by Dr. Katherine Flegal. The study looked at data related to BMI and mortality. The study looked at data from studies worldwide which examined the link between BMI and any cause of mortality. The Flegal study found that, while people who were considered to be "class 2" (BMI between 35 and 40) or "class 3" (BMI >40) levels of obesity did indeed have higher levels of mortality for any cause, those with a "normal" BMI (between 18.5 and 25) actually had a higher risk of dying (of any cause) than those in the overweight category (BMI between 25 and 30). And in fact, those who weighed in at a "class 1" level of obesity had no higher risk of dying than normal weight individuals.
Okay, I just spent all kinds of time and energy losing weight and now this #%^@$ study is telling me that I'm not increasing my chances of living longer. And this opinion piece in the New York Times seems to agree! Gah! I'm calling Pizza Hut right now!
I am kidding, of course. Actually, I found this article in Forbes that breaks it down nicely. I find that I really agree with the level-headed, analytic approach that the author takes to the Flegal study.
The problem with obsessing about BMI is that it is not the only indicator of health (note that the study looked at ANY CAUSE of death) Frankly, I hate the BMI. It has been the bane of my existence during this weight loss process because, even though I have lost over 125 pounds and even though I look great and I feel great, my numbers are spectacular (my cholesterol, my blood pressure, my triglycerides...), and I am healthier than I've been my entire adult life, the BMI still says that I am "overweight." Blah! And a big middle finger salute to the BMI.
Though the BMI is useful as one tool to determine a healthy weight, I don't think that one should obsess over it. As the author in the Forbes article points out, there are several other factors that are just as, if not more, important. Cardiovascular fitness, losing fat around the midsection, cholesterol, and blood pressure are all important. Being a non-smoker or quitting if you are a smoker is important. Exercising regularly is important. So, we should not ignore the BMI entirely, it is important as one measure of health.
The danger I can see with the Flagel article and in articles like the New York Times opinion piece is that people who really do need to lose weight will look at these things and decide that they are not really unhealthy enough to make the difficult changes they need to make. Why go through the hard work of changing your lifestyle if the payoff is not going to be a longer, healthier life? That mindset is dangerous. One thing that I have learned on this journey is that weight loss is a complicated and, surprisingly, controversial issue. Oversimplifying data that shows a relationship between obesity and health risks to the point of overemphasizing the importance of BMI in one's health profile is dangerous. So is oversimplifying data showing that mortality risk is lower for people who are "overweight" according to the BMI.
In my experience, losing weight (and lowering my BMI) has improved my health in more ways than I can count. I used to get migraines, I don't anymore. I used to get winded WALKING up stairs or up hills, now I can run up several flights of stairs without getting winded and I can walk 15-20 miles in a day. I used to get tired quickly and had no energy to do anything by sit on the couch at night - now I am active and go out nearly every night. I'm happier. I have more energy. I look better. I'm more confident. I don't get heartburn anymore. My cholesterol (and my risk of heart attack and stroke) is WAY down. My blood pressure is fabulous. My blood glucose levels are normal (no more borderline diabetes)....and on and on..... So, in the end, regardless of what the BMI says, I'm way more healthy. And it was / is totally worth the effort. So, while the experts are arguing about the importance of the BMI, I'll be enjoying my time learning to swing dance with my husband, hiking (Iron Mountain this weekend!), swimming, and kayaking...all thanks to my weight loss and the health benefits that came with it.