There is a new study out that reinforces a point that I have made repeatedly, that focusing on people’s weight (as measured by the Body Mass Index) instead of their health is the wrong way to go and in fact may be harmful because it discourages people from a healthy lifestyle, despite all its benefits, if it does not result in weight loss. As one of the authors of the study says:
Given the number of papers my supervisor, Dr. Ross, and I have published on the topic, I would argue this is the biggest drawback of using BMI: it doesn’t always change even though you may be getting healthier. This is particularly so if you adopt a physically active lifestyle, along with a balanced diet, but are not necessarily cutting a whole lot of calories. This lack of change in BMI or body weight is all too often interpreted as a failure, resulting in the disappointed individual resuming their inactive lifestyle and unhealthy eating patterns.
However, as we have argued most recently in a paper in the Canadian Journal of Cardiology, several lines of evidence suggest that weight loss or changes in BMI are not absolutely necessary to observe substantial health benefit from a healthy lifestyle. Thus, an apparent resistance to weight-loss should never be a reason for stopping your healthy behaviours.
First, it is well established that increasing physical activity and associated improvement in cardiorespiratory fitness are associated with profound reductions in coronary heart disease and related mortality independent of weight or BMI. Second, exercise (even a single session) is associated with substantial reduction in several cardiometabolic risk factors (such as blood pressure, glucose tolerance, blood lipids, etc.) despite minimal or no change in body weight. Third, waist circumference and abdominal fat (arguably, the most dangerous fat) can be substantively reduced (10-20%) in response to exercise with minimal or no weight loss. In fact, significant reductions in fat mass often occur concurrent with equal increases in muscle mass in response to physical activity – equal but opposite (and beneficial!) changes which are not detected by alterations in body weight on the bathroom scale, and thus BMI.
But in this media culture that idolizes thin people and sets them up as the standard for attractiveness, this new message will have a hard time gaining acceptance, despite the fact that losing weight and keeping it off is very hard to do. People will try to do that rather than the more accessible goal of healthy eating and regular exercise, despite the greater benefits of the latter.
Pediatric researchers have found that when they put children on diets, the kids just gain weight. They are also at increased risk for eating disorders. I always encourage patients to focus on increasing their exercise endurance. Also to compliment themselves for blocking binging or eating when not hungry but not to criticize themselves if they make mistakes
From the point of view of the media, advertisers, and the diet industry, that’s a benefit. People who fail keep coming back for more, and their insecurities make them easier to sell stuff to. The very last thing the media-industrial complex wants is happy, healthy people.
Good morning Mano,
I don’t doubt the science behind the study, nor your own writing, but I do serious question the effectiveness of a health-focused approach because individuals have limited access to tools to objectively measure health.
Writing as someone who lost 80 pounds three years ago (regained 45 pounds of that last year and shed again 20 pounds this summer to my present weight of 210 pounds headed back to my target of 185 pounds (for those doing the math, I’m a 59-year-old male whose height is six-foot even).
My weight loss was prompted (and wonderfully supported by) my doctors at the Veteran’s Administration who stopped an annual physical to take me to the emergency room because they found my blood pressure to be dangerously (we’re talking stroking-out territory) high.
They sent me home after 8 hours with my blood pressure pharmaceutically reduced to a safe number, a prescription for Linsinopril and a digital blood pressure monitor (both fully covered by the VA). This last is the most sophisticated, health-measuring device in my weight loss toolbox. In addition to the monitor, I went out the next day and purchased a digital body scale to measure my weight and a gram scale to measure my food. Weight loss is all about measurement.
I became absolutely obsessed with measuring my weight, my blood pressure, my food (in grams, volume is worthless) and meticulously recording all the date in a notebook. I came to think of all this as my body hack experiment. In six months I was off the Lisinopril and in nine months I was at my target weight, the same weight (and clothing size) as I was at 17.
That I could measure weight, food consumption and blood pressure on a daily basis was critical to my experiment. I understand the problem with the Body Mass Index—particularly if you simply rely on the calculations and tables—but I took the time to get a true reading using the Bod Pod at Lorain County Community College and feel comfortable with those measurements.
I also used the hip-to-waist measurement guidelines and found them helpful in a general way, but the key was weight measurement and keeping my eye on the target established by my VA doctor whose practice was focused on weight issues and heart health.
Why did I regain 45 pounds last year? Stress. I allowed some changes in my work routine to accommodate three students that disrupted my long-established practice of writing first thing in the morning and shifting to my teaching work late in the forenoon. Fixing that and seriously ratcheting down my stress (mediation and long walks with my dog help greatly here) has put me back on the path to my goal weight again.
All of this has taught me that objective measuring and constant vigilance are critical. As author Cory Doctorow, in Long-term weight loss considered nearly impossible wrote recently:
Such attention to detail demands details to pay attention to. I can offer anecdotal information about my health, but that data is dubious at best. A healthy-weight life hack is like a chemistry laboratory experiment, you can’t guestimate and record how you feel about volumes, weights, pressures or temperatures, you need the tools to precisely determine those measurements.
Do all you can to make today a healthier day,
Jeff Hess
Have Coffee Will Write
There was a recent study on how many firefighters are overweight or obese. I took it with a grain of salt simply because I suspected they did everything from BMI. If firefighters worked out more, they could trigger as overweight/obese just because muscle is denser than fat.
Heart problems apparently are very common for firefighters. So it just makes research like this very fuzzy to me.
By “suspected” I mean that yes they do everything from BMI.
I’ve heard it said for the last few years that it is better to be fit and overweight, than normal weight and not fit.
@doublereed
I wouldn’t be surprised if heart problems were an issue for firefighters, it’s a pretty stressful job.
The other thing is most athletes get a warm up before they jump into a high intensity activity. Firefighters don’t quite get that so they’re probably going from rest to extremely active in a very short time.
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I think the focus on BMI is that it’s just easier (and lazier) for someone to take one number and decide ‘you’re fat’ than it is to determine whether or not someone is healthy (a bit harder.)
A lot of people attempt a “healthy lifestyle” (which isn’t so much an objective thing as it is a collection of stereotypes) and abandon it not because they expected weight loss or lack self-control, but because despite all the hype the supposedly better way of living just makes them feel like crap. There’s a lot of talk about how “the body” adapts to this or that change, but for most such claims there are people whose bodies don’t actually respond that way.