More evidence that the ‘overweight’ are at the lowest risk of death
Posted on 10 July 2009
The standard way of assessing weight as it relates to health is the body mass index (BMI)
Published July 10, 2009 . Filed under: Food and Medical Politics, Weight Loss
It’s obvious that there has to be a distinction between healthy muscular/strong/fat people and unhealthy skinny people.
These weight/risk of death studies go back to the 19th century where they were originally led by life insurance companies. One issue that has been identified as a possible confounder of the more controversial higher weight=lower risk of death studies, is whether or not they exclude smokers and the chronically ill. Since both smoking and chronic and degenerative illness are associated with lower weight, clearly – unless these have been discounted – the findings will be flawed.
There are also epidemiological studies, for example conducted on Okinawans, that low calorie consumption and low body weight are associated with gains in longevity.
July 10, 2009 @ 9:11 am
I am confused. We are often told on this site that waist circumference is the most important indicator in terms of health risk, including heart disease, diabetes and some cancers. Surely not everyone in the BMI overweight category in these studies also happened to have the waist measurement deemed healthy for their gender?
My BMI is 25, yet my waist measurement is 3 inches more than is recommended for a woman. So, should I lose weight, thus reducing my waist size and my BMI and, according to these studies, increase my risk of dying…..?!
July 10, 2009 @ 3:59 pm
[...] people would live longer, but as it turns out, several studies are showing that they die sooner. Dr. Biffa’s blog recaps the results of two recent studies that show surprising results: Compared to individuals in [...]
July 10, 2009 @ 5:49 pm
Jane
The blog here suggests that the BMI categories are misleading when applied to a population (they give a false impression, I think of the health ‘hazards’ of being overweight. When applied to an individual, the BMI is even more useless, as it tells us nothing about body composition nor fat distribution. So when looking at an individuals (e.g. you) I think the BMI value has practically no relevance at all.
I suggest you ignore it, and focus (if you want) on more useful body measurements such as, as you the suggest, waist circumference.
July 11, 2009 @ 7:55 am
Does anyone know where the definitions for BMI i.e. healthy, overweight etc. came from? It seems that the calculation and definition came about arbitrarily and there is no easily accessible evidence what science this was founded on.
July 14, 2009 @ 3:08 pm
Changes in BMI may be more useful than the number per se.
I’ve always been on the lower end of normal and was actually underweight while I had undiagnosed gallstones.
However this never stopped me from having severe Impaired Glucose Tolerance, only a gnat’s whisker away from diagnosible diabetes.
After being attacked by a Dietician my BMI rapidly increased to borderline overweight, and equally rapidly decreased back to *my* normal when I started eating a rational diet instead.
Meanwhile one of my aunts, with a different subset of the same genes, was comfortably overweight with “the blood pressure of a 30 year old” in her eighties, while my tiny mother has had hypertension for 40 or 50 years. This seems to be a distinct familial pattern where the “overweight” measure significantly better on cardiovascular risk factors than us skinnes. Maybe this is not just a pattern in our family but is more widespread.
Michael Eades calls it “metabolic obesity” where you measure like an obese person without the overweight. Presumably there’s also a corollary of “metabolic slimness” where your BMI is higher than your risk factors.
July 16, 2009 @ 4:00 pm
Weight itself might not matter as much as the reason why someone is overweight. Some people have low thyroid and this can affect the heart and also cause weight gain. Some people are genetically prone to weight gain even if they eat a good diet. Others ar overweight because they eat junk. These are probably the ones who get ill because of what they not because of the weight. So obesity may be a symptom and not an illness. Hilda Glickman nutitionist
July 17, 2009 @ 8:28 am
I think the key measure here is quality of life & health while alive. Measuring death rates as related to BMI, weight, etc, is a bit spirious in my mind. For example, having to spend large periods of time sitting on renal dialysis is quite distinct, in terms of quality of life, from someone who gets to spend the same period of time riding their bike in the sun. But both individuals could however die at the same age/stage of life.
There are any number of factors that relate to premature death & high body fat levels are one of those. What we want however, is not necessarily a population that lives any longer, but one that is healthy for the time it is alive.
As a clinical nutritionist & exercise physiologist, I get a bit uncomfortable when I see headlines such as “More evidence that the
July 18, 2009 @ 11:47 am
Another reference by Flegal:
JAMA. 2005 Apr 20;293(15):1861-7.
Excess deaths associated with underweight, overweight, and obesity.
Flegal KM, Graubard BI, Williamson DF, Gail MH.
National Center for Health Statistics, Centers for Disease Control and Prevention, Hyattsville, Md 20782, USA. kflegal@cdc.gov
RESULT.
Overweight was not associated with excess mortality (-86,094 deaths; 95% CI, -161,223 to -10,966). That is, Overweight individuals LIVED LONGER than normal weight persons!
Check for yourself on Pubmed. This study has been widely ignored by the medical establishment.
BUT ONE WOULD NOT WANT TO SPOIL A GOOD STORY WITH HORRID FACTS.
Incidentally the first paper published was shown to have had arithmetic mistakes. The above paper had to be written to correct the errors. BEWARE of medical statistics!
July 21, 2009 @ 12:03 pm
There are clearly some protective advantages in carrying excess fat, particularly in conditions that cause inflammation and cell damage. Fat and obese ICU patients tend to have better outcomes than thin or underweight patients, – a 30% better survival rate. These figures are, like those above, adjusted for age, smoking and wasting diseases. There are also increased risks associated with carrying, excess fat. On the whole I would tend to agree that excess fat, below the extremes noted above, is largely benign and the case against it vastly exaggerated.
To be specific, the anti-fat stance is mostly, in my opinion, a matter of fashion, not medical concern.
Exercise is far more important, with regard to health, than the percentage of body fat. Even with this we manage to scare people away from it more than get them to take part. Firstly; we must abandon the “minimum requirement” that health professionals insist is needed for improvement. We overwhelm people with images of pain and hard work before they even begin to exercise. My own view is that ANY increase in physical activity, no matter how little is a good thing. I know several, previously inactive, people who have improved their standard of life simply by buying a Wii games console. On the whole I just encourage people to do a little more each day and emphasise that I mean a LITTLE. This way they don’t even notice that they are increasing the amount they do and tend to stick at it much longer, until low and behold, they are doing a useful amount of exercise regularly, as part of their daily routine. Instil the habit first, this is the most important aspect of regular exercise, then build the amount – slowly.
August 30, 2009 @ 6:56 pm