A new definition of obesity has just dropped. It’s set out in a paper published this week by The Lancet Diabetes and Endocrinology journal. Authored by a “commission” of 58 experts drawn from leading medical institutions in several countries, it’s likely to prove influential. Indeed, it has already been covered by Nature, New Scientist and the BBC. What’s more, the new definition has now been endorsed by the Royal College of Physicians, among others.
In short, this has the potential to change the way that obesity is diagnosed and treated — which matters to millions given that 29% of Britons and 38% of Americans are currently defined as obese. However, we’re in danger of making a big mistake, primarily because the paper’s argument is badly flawed.
It begins by making a perfectly valid point, which is that the standard way of defining obesity — Body Mass Index (BMI) — leaves a lot to be desired. As a simple formula based on height and weight, BMI is a convenient way to categorise individuals and entire populations. Perhaps that’s why health bureaucracies are so stubbornly attached to it.
A key issue is that BMI disregards body type, as if a broad-chested guy and a beanpole of the same height are meant to weigh the same. Athletes of various builds are also messed around, because BMI makes no distinction between muscle mass and adipose tissue — i.e. fat.
So, yes, we need a better framework. Unfortunately, what the Lancet study authors propose really isn’t it. They want a distinction between “clinical obesity” and “preclinical obesity”. The first is defined as a “chronic systemic illness […] due to excess adiposity”; the second is a “state of excess adiposity with preserved function of other tissues and organs”.
This implies that there is a fundamental distinction between the two states. Indeed, the paper goes on to characterise the preclinical/clinical divide as “health vs illness”. Imagine a paper authored by leading medical experts that proposed a similar distinction between preclinical and clinical smoking. It just wouldn’t happen, because there is no state of being a smoker that can be described as healthy.
The same should apply to obesity. Though the paper allows that the preclinically obese are at a “varying, but generally increased risk” of becoming clinically obese, it underplays the links between the two. One doesn’t suddenly flip from one state to the other: rather, the damage done by “excess adiposity” accumulates to the point at which it becomes diagnosable as disease.
The worst thing about the new definition is that it runs counter to a long overdue shift in how society views medicine. It shouldn’t just be about treating people when they get sick, but intervening earlier to halt the process by which most of us are getting sick. This applies as much to poor diet, lack of exercise and obesity as it does to smoking. The last thing we need now is a new definition that reinforces an outdated paradigm.
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SubscribeAs each week goes by I find Unherd to be the most ridiculous media outlet I have ever come across.
What is up with this writer? He is taking the fight to a non-existent problem.
This from the Lancet.
“The new, evidence-based definition distinguishes “clinical obesity”, a chronic, systemic disease state directly caused by excess adiposity, from “preclinical obesity”, a condition of excess adiposity without current organ dysfunction or limitations in daily activities but with increased future health risk. Given the limitations of BMI, the Commission uses other measurements of body size (waist circumference, waist-to-hip ratio, or waist-to-height ratio), in addition to BMI, to define obesity status.”
So body shape is taken into account. And it is made clear that preclinical obesity does pose a health risk for the future.
There is nothing wrong with this approach. What is Unherd’s problem?
At the state grammar school I attended in the seventies we had compulsory sport three times a week. Later, at college in the US I met Americans who had trained and played sport at the end of every school day – with weekend boot camps as well.
My own kids in the UK system get one compulsory PE session per week which is quite easy to avoid. There are a lot more fat kids than there used to be.
The food today I believe is the biggest culprit. 40 years ago all the processed foods (that don’t fill you up for long) simply didn’t exist, and mum was at home all day to make a hearty meal out of meat and veg which is much harder to get fat from eating as you have to eat colossal amounts of it to do so. You can’t outrun a bad diet after all
A lot of people think the obesity epidemic is driven by poor diet and/or lack of physical activity. Trouble is, historical research and statistical analysis shows that is not the case. Why we are getting fatter (though the increase may have plateaued) is a mystery. But we know that ultra-processed food is not the problem.
I suppose Unherd, and their editors, here a Peter Franklin, are annoyed with the Lancet for treating obesity as a life endangering medical state.
As opposed to the view of the Far Left set out in Fat Studies, that people are named and shamed as obese, and so this is a Social problem, along with Race and Gender.
Is that the new paradigm? Leftists, quite sensibly, never clearly say what they mean, to prevent it from being challenged and refuted. Instead they speak in their Leftist code.
That is the only explanation I can come up with for this bizarre article. Anyway, typical Unherd pap.
The main point about BMI is that it’s a measurement, rather than just a clinical definition.
Therefore, someone with a BMI of say, 24 (upper normal range) who a year later has a BMI of 26 can measurably be said to have put on weight and therefore take steps (if so inclined) to reduce their BMI.
Similarly, someone with a BMI of 28 who a little while later finds they now have a BMI of 31 (regardless of body type) knows they’ve moved into a state of obesity that threatens their longevity through increased risk of disease.
Using “pre-clinical obesity” and “clinical obesity” which in any case are subjective opinions taking “body-type” into account which might vary between clinicians, isn’t anywhere near as helpful, even where BMI is still measured.
I think you’ll find it is much easier to just measure your own weight to track whether you have lost or gained weight, instead of converting it to BMI. I do think that BMI has utility, it is an easily understood metric that can be used in combination with whether or not the person is actually fat. For example, a doctor would never recommend their pro athlete patient to go on a diet because their BMI is over 30, but that is something they can easily point to for their middle aged couch potato patients.
Except a Dr did recommend a world class level badminton player I know should go on a diet because his BMI was officially high even though he was clearly fit, lean and healthy.
Three things here. The first is that all of this discussion and paper-writing time is purely for doctors and not for their patients. In an ideal NHS, where you could see a doctor every week for regular consultations, then it might….just might, maybe, possibly…. make a difference. But in the real world, is it important?
Secondly, for the patient you do not want any confusion. In the (fictitious) world where people take responsibility for their own weight, it is they -those people- who have to have a clear view about their obesity. Confusion is not needed.
Thirdly, however wrong BMI might be it is a guide which everyone can understand. There is a history of how BMI has increased over the years, there is a meaningful comparison of BMIs between different countries and it is important for reference that we continue to use it. (I know that the article expressly says that we will still use it but just making the point).
I have found a great way of telling whether I am obese. I look at myself in the mirror and weigh myself.
The way to check if you are getting obese is when all your clothes shrink simultaneously.
Another example of why the title of expert means little.
On first reading the argument for the change the reaction is perhaps ‘too complicated, folks won’t understand’. But perhaps that’s too hasty. Being told you are on the path to being clinically obese with more specific ill health but not there yet and pre-clinical may in fact help. You have a chance to arrest the direction.
BMI is too crude and labels too many incorrectly so it does need to be changed. It’s lost credibility. What the proposal isn’t doing is removing the need for categorisation (even label). It’s not gone Woke so to speak where anything conveyed might get twisted as ‘unsafe to hear’ B/S. So I think it’s worth pausing and thinking a bit more about what’s being suggested.
As regards the obesity epidemic, one wonders too if some of this makes Ozempic prescribing a little easier – only funded if clinically obese? However as seems to be happening in the US Ozempic appears to have slowed, maybe even flattened, the increase in Obesity however it’s being paid for. It’s a separate debate as to whether this reliance pragmatically good or not.
Although I am now a retired GP and free of the decisions of 58 pole climbers making criteria for diagnosis, I can spot a fat person at 200 metres. Obesity is a nonsensical term. Being fat is what matters to one’s health. Fat people occur in all advanced societies due to an ability to endlessly gorge. Unless the fat person is unaware of the dangers, has a condition made worse by being fat or has a diagnosis to explain it there is no need to inform them nor treat it. Many decide to remain fat. There is much effort wasted on pamphlets written by dieticians and social workers on fatness which could be used to treat children or the ill adult. There will be significant money spent on splitting this most recent hair by these specialist professional conference attenders. The only people to profit will not be the patients but the specialists and so-called expert sources open to financial influence such as The Lancet, The BMJ, Nature and the latest entrant in to medical publishing, the BBC.
No need for formulas of any kind. Don’t wear clothes with an elasticated waist you’ll soon know if you are getting fat. Don’t eat ready meals or take away food (it’s shit) Good line from someone on an American TV show once “if it’s advertised don’t eat it” Learn to cook. Making healthy nourishing food is easy and cheap with a slow cooker. You have plenty of time if you cancel your TV license and switch of the TV (it’s also shit and bad for your mental health)
To repeat the key “take away” – IF IT IS ADVERTISED DO NOT EAT IT.
I’m lost.
How, specifically, is obesity to be measured under the proposed definition? I understand that it makes a distinction between “clinical” and “pre-clinical” obesity and that it relates to “adiposity” but does the proposed measure of “adiposity” include BMI or is that being dropped altogether? What is the proposed definition of “adiposity”? Why does the author infer from the definition that there won’t be any suggested medical intervention when someone is diagnosed with pre-clinical obesity?
Come on Peter Franklin, you’re a good journalist and you can do better than this!
Here is the US the “Body Positive” movement gave rise to the view that being fat/obese/over-weight was fine. Look at photos of Americans in 1950s and you do not see such a preponderance of heavy people.
I think this is a combination of many factors including foods available (much more packaged high calorie foods), our personal choices around portions, what to eat, and how much to exercise, and there are no costs to being over-weight. Imagine if to have your health insurance renewed, you had to step on a scale in a medical office and based our medical premium would be determined based on the reading.
“(medicine)… shouldn’t just be about treating people when they get sick, but intervening earlier to halt the process by which most of us are getting sick.”
A prescription for exactly the kind of overbearing health-police action of the sort we saw and rebelled against in the Covid pandemic. https://www.wsj.com/articles/covid-worsened-america-rage-virus-for-which-theres-no-vaccine-lockdown-vaccine-mandates-ron-desantis-stanford-masking-2670cd39?st=vnBfzi&reflink=desktopwebshare_permalink