Could we be getting to the point where your doctor says you’re definitely obese and that’s just fine?
Maybe and, if we do, it will be because of the “obesity paradox.” In brief, growing evidence suggests all of us should take a deep breath and chill a little over older adults who are overweight or a little obese. Not morbidly obese – which is a medical term, by the way, and not an editorial comment – but rather a specific weight classification technically known as obese (or category 1 obesity). That’s because once obese people develop heart disease, they live longer than those who are thin (what has previously been considered normal or even optimal weight - See "me"). Plus, they live longer than those who are morbidly or super obese (again, that’s medical terminology, not editorializing).
I was reminded of this recently while listening to results of the largest clinical trial of people with heart failure and preserved ejection fraction. Ejection fraction is that small portion of blood pumped out of the heart with each heart beat. About half of all people with heart failure have a fairly normal or “preserved” ejection fraction. Like many studies in the last few years, when the I-PRESERVE trial data were analyzed to determine the effect of obesity on outcomes like death or hospitalization, the best results were seen among those people who were obese. The worst outcomes were seen in the thinnest and the fattest groups of individuals.
The stylishly thin Dr. Markus Haass of Theresien Hospital Mannheim, Germany, finished his presentation in November at the 2009 American Heart Association meeting by saying, “If I ever develop heart failure, I had better gain some weight.” In taking questions from the audience, a San Francisco doctor stood up, acknowledged his own obesity, and admitted “I really like these results.” The audience laughed and he added, “This is more evidence that the definition of normal body weight may be set too low.”
Just What is Normal?
Doctors use body mass index or BMI as an important measure of body fat. What is your BMI? All you need to know is your height and weight, then use a calculator like the one here to determine your BMI: http://www.nhlbisupport.com/bmi/
These are the categories used to define weight:
• Underweight = <18.5
• Normal weight = 18.5-24.9
• Overweight = 25-29.9
• Obesity = BMI of 30 or greater
In recent years, doctors have refined the category of obesity even further to include:
• Any BMI ≥ 35 or 40 is severe obesity
• A BMI of ≥ 35 or 40–44.9 or 49.9 is morbid obesity
• A BMI of ≥ 45 or 50 is super obese
A Little History
In 2002, a study of nearly 10,000 patients surprised a lot of people. Investigators looked at patients undergoing a common heart procedure called angioplasty and evaluated the results based on BMI. While the procedure was equally successful in all the weight groupings studied, normal BMI patients had a higher incidence of major in-hospital complications, including cardiac death and this difference was statistically highly significant (p = 0.001). After 1 year, more people with normal BMI had died compared with overweight or obese patients (p < 0.0001).
The study raised a few eyebrows, but because the results were so different than what was expected, it was largely dismissed as a likely anomaly. Then in 2005 (after more reports of such “anomalies”) Katherine Flegal, PhD, who is a senior researcher at the Centers for Disease Control (CDC), published a paper in JAMA that concluded that overweight and obesity accounted for far fewer deaths than thought. Specifically, instead of the 365,000 deaths in 2000 (the CDC’s own numbers) her study estimated that only 112,000 deaths in the US that year were associated with obesity (BMI of 30 or higher).
Dr. Flegal also found that people who were overweight but not obese (BMI of 25 to less than 30) were less likely to die during follow-up than normal weight individuals (BMI of 18.5 to less than 25). The greatest risk of death was among the leanest (BMI <18.5) and among the most obese (BMI of 35 or higher.) In other words, as you get older, it’s looking like being a little bit chubby is actually protective against death.
He Said What?
Back to the presentation I talked about earlier. After the audience member said he and his waistline were relieved and encouraged by the results, Dr. Haass who presented the I-PRESERVE data said: “It is better if you are young and have no major chronic disease to be a little on the lean side but once you develop heart failure or have a (heart attack) you better have a little so-called overweight because this is prognostically an advantage.”
Think about that statement: Once you have a heart attack or develop heart failure, you need some excess weight. Can you imagine your doctor saying, “Well, you’ve had a heart attack, so I’m giving you a special diet because you need to put on a few pounds.” As you might imagine, there are a number of doctors who are nearly going ballistic over data that even hints at such a recommendation.
Yet, if you have a BMI that makes you overweight or a little obese, maybe your doctor should not have you worry too much about weight loss. Certainly, once you have had a heart attack or have developed heart failure, you have plenty of other things to worry about, but maybe your weight shouldn’t be one of them – unless, of course, you have a BMI of 35 or higher, where all the data suggests you need to lose some weight.
There have been a total of 84 papers published since that first article in 2002 referred to this “obesity paradox,” which isn’t nearly enough data to bring an end to the debate. (I suspect it’s just getting going. Medicine moves slowly, sometimes even glacially.) But perhaps we need to stop obsessing so much about gaining a few pounds as we age, because if there is one thing pretty obvious from decades-worth of data it’s how massively unhealthy yo-yo dieting is. This never-ending loop of weight loss and weight gain is absolutely not healthy for anyone. So, you’re older and a little overweight? Frankly, that’s probably just fine.
