Fairfax has a piece on myths about obesity that is sensible and properly science-based, and which they are promoting in the banner area of the front page? Maybe there’s something to all this approaching-2012-apocalypso after all.
The layout is better in the dead-tree edition, where the SMH felt no need to illustrate it with a headless torso as they have done in the web version (at least it’s not an OMGDeathFatz headless torso this time).
Gary Egger and Sam Egger originally published a version of this article in Australian Family Physician, and the gist is this:
We assessed the best available evidence on weight loss and maintenance and used this to compile a 20-statement survey – with true or false responses – which we then gave to two groups of people: 173 GPs and 129 truck drivers and tradesmen.
We found doctors were almost as confused as truckies and tradies. The doctors disagreed with most of the supporting evidence on 40 per cent of our questions, the others on 49 per cent.
Another failing of the web edition is that it does not reproduce the table of results for the survey which is shown in the dead-tree edition. Here’s the data in the table seen in the dead-tree version reproduced manually using a spreadsheet:
| Tradesmen | Big Fat Lies | True/False | Doctors |
| %incorrect | SMH 2009/11/19 page 21 | %incorrect | |
| NUTRITION | |||
| 38 | Fruit juice is about as fattening as beer | TRUE | 20 |
| 80 | Humans need 8 glasses of water a day | FALSE | 79 |
| 43 | Peanuts are a healthy food | TRUE | 42 |
| 74 | Dairy products can help weight loss | TRUE | 73 |
| 33 | A low protein diet is best for weight loss | FALSE | 10 |
| 55 | Fat people don’t get more hungry than lean people | TRUE | 62 |
| 76 | Chocolate is healthy provided it is ‘dark’ | FALSE | 45 |
| 27 | Spicy foods make you eat more | FALSE | 32 |
| 27 | Vegetable juice is healthier than fruit juice | TRUE | 34 |
| 34 | Coffee causes cancer | FALSE | 28 |
| EXERCISE | |||
| 49 | Sit ups will not help reduce fat off the waist | TRUE | 49 |
| 77 | Exercise is better than dieting for weight loss | FALSE | 60 |
| 52 | Swimming is better than walking for weight loss | FALSE | 27 |
| 69 | Weight lifting is good for fat loss | TRUE | 62 |
| 77 | The best measure of body fat is body mass index | FALSE | 23 |
| 39 | You lose more weight doing exercise you are good at | FALSE | 56 |
| 68 | An obese person can be fit and healthy | TRUE | 47 |
| 34 | You have to ‘bust a gut’ to lose a gut | FALSE | 33 |
| 25 | Sauna baths are good for fat loss | FALSE | 10 |
| 8 | Exercise can increase depression | FALSE | 2 |
It’s depressing to think that nearly 3 out of 4 in both groups believe incorrectly that dairy products do not help weight loss, that more than 1 in 2 in both groups believe incorrectly that fat people get more hungry than lean people, that roughly 2 in 3 in both groups do not know that weight lifting is good for burning fat while nearly 1 in 2 believe incorrectly that sit-ups will burn abdominal fat. On the other hand, at least 3 out of 4 doctors agreed that BMI is not a good measure of body fat, which seems to represent some sort of progress with the medical education on that even if it hasn’t trickled down to Joe Tradesman.
On the gripping hand, doctors don’t seem to have absorbed much in the way of basic biomechanics, believing falsely that one loses more weight doing exercise that you are good at, while the truckies/tradies seem to know the truth – the better you are at something the more efficient you are, therefore the less energy you will burn while doing it. (This effect is possibly/probably confounded somewhat by the aspect that if you are good at something you are more likely to enjoy doing it, and are therefore more likely to do it for longer and thus burn more energy than doing something else for a shorter interval, so this question is not as clear-cut as perhaps the authors intended).
This article is cross-posted from Hoyden About Town.
Hmmm. Some of the questions seem to be pretty obtuse and misleading. I mean, surely whether “dairy products can help weight loss” depends entirely on how much is consumed, and what the person’s other dietary and exercise habits are. Ditto for peanuts being a healthy food. And the expression “you have to bust a gut to lose a gut” is a metaphor, so how can it be true or false in a factual sense? I reckon the SMH gets a bare pass for this one.
How can we expect GPs to have decent knowledge about nutrition when it is such a minimal part of their syllabus and what is covered tends to be a very traditional view of diet? I talked to a medical student at one of Australia’s leading university’s about what is currently covered and it is minimal. She said “oh we hand out leaflets (eg from the Heart Foundation) or refer to a dietician or nutritionist”. I asked her if she knew the difference between a dietician and a nutritionist and she admitted she didn’t.
Hand-balling advice about diet to the organisations that tend to supply GPs with handy information brochures for clients is also a big worry. Will groups like the DAA publicly say anything against meat or dairy let alone cornflakes or chocolate drinks http://www.daa.asn.au/index.asp?PageID=2145833463 ? And as the McDonalds healthy heart tick meals imply, can the Heart Foundation really be trusted to pass on unbiased advice about food?
From the article:
I agree it’s not a slam-dunk, but given that “cut out all dairy products” is fairly common dietary advice? The evidence seems to show that cutting all dairy products probably have more disadvantages than advantages. The question would, however, probably have been better phrased more like the common idea they mention – “all dairy products cause weight gain”.
I agree TT – it was the phrasing of the question that bugged me, rather than the underlying issue they’re getting at.
The problem with this survey is that it all depends on how you interpret each phrase. Certainly my response to the vast majority is “kind of, depends what you mean by x”. For instance, fat people get more hungry than thin people. It depends which component of hunger you mean. Immediate satiation is similar while long term food intake modulation is evidently not. Hence yes and no. An obese person can be fit and well depends on how you define well. If you mean they are without risk factors for serious illness of a significant nature then no, in the same way that someone with hypertension cannot be. Hence, yes and know, what do you mean? Peanuts are a healthy food, except for the buckets of fat and the fact that a not insignificant group try to drop dead if they are standing next to you when you open the packet.
Oh, and I haven’t read it but I’d look reallllly closely at the disclosures on the low fat dairy study.
Ambiguous subjective questions lead to contradicting answers; who would have guessed? The only thing this proves is the lack of communication skills on the part of the scientists.
legitimate question in the study:
8 glasses of water. 80 – 79
cofee causing cancer 34 28
BMI 77 -23
sauna baths 25 – 10
depression 8 – 1
The rest most gps would answer “it depends, sort of” and then give an explanation.
The only one that seems oddly high compared to evidence is the 8 glasses of water… but it’s not exactly BAD health advice to tell people to drink water either so it’s a wash really.
Not sure I agree with this one. Clearly, walking can be as effective as swimming if one merely wants to burn calories. Swimming however, is low impact, so for those above 55 or others wanting to keep pressure off the lower back, knees etc swimming or aquarobics may be a better strategy. You’re also more likely to get up to aerobic exertion when swimming than walking. If you are more likely to walk aerobically than swim at all, then walking is better. “It depends” would be my answer.
I’d like to see the mandatory inclusion of a dedicated “it depends” box to tick on all academic surveys like this, just for the pilot phase.
Any question that gets more than x percentage points of “it depends” responses can be thrown out or reworded and retested.
That’s what I did both times I had to design a survey instrument, and it worked well. At least a couple of questions each time whose wording I was pretty happy with turned out to confuse people or limit response options unnecessarily.
e.g. “Spicy foods make you eat more”
Who is “you”? If it’s me, then this statement is certainly true. I love spicy food. If it’s “one”, then I’m fucked if I know.
Basically, most of these questions fall into this category.
Is there a link to the actual study and questions?
Was it a phone survey – online or face to face?
Sounds like to he sort of thing I would go yeah yeah dunno no whatever.
As others have pointed out most answers would begin with it depends what you mean, explain the details.
“Dairy products can help weight loss”
I’m thinking of crap load of cream slopped over a lemon tart with icecream followed by a huge hunk of cheese. Nope can’t see how that helps weight loss.
And don’t jockeys and boxers use a sauna to get their weight down for a weigh in? Well at least in the movies they do.
Non-dairy saunas, sure.
FXH, they use a sauna for temporary weight loss, because they come out of it severely dehydrated. Once they drink the mandatory, health-inducing 8 glasses of water, they just pack the pounds straight back on.
I agree that several of these questions could do with rephrasing.
Weight Management: Facts and Fallacies
Back to the dairy/weight loss issue. Low fat dairy foods usually have higher lactose. Take out the fat and add more sugar. Not necessarily the best weight loss equation that I’ve come across.
@Dr S:
It also depends on how you define obese, which is the point of the BMI question. Most professional male basketballers and football players are clinically obese as measured by the BMI because it does not accurately reflect the body composition of the very tall or the very muscular. Many people who are BMI-obese are only carrying small rolls of fat, and some people who are carrying more fat are nonetheless very active anyway.
What assumptions underlie your equating obesity with risk factors such as hypertension? The large subset of obese people whose blood pressure, lung capacity and cholesterol (and other blood) readings are all within normal limits (and sometimes spectacularly good): exactly what other risk factors besides a figure on a scale can you point to? Is obesity the cause of certain illnesses, or is it a side-effect of some illnesses/conditions rather than a sign that inevitably illnesses are just waiting to happen?
I think the point about weightlifters having an obese-level bmi is a bit of a furphy. Everyone knows that bmi is a good measure of obesity in those who don’t have special lifestyle considerations, i.e. your average sedentary office-worker, and that other measures – body fat percentage, hip-waist ratio, etc- are important when dealing with people outside this range.
But more generally, discussion of bmi is also about discussing the sensitivity and specificity of a screening test, i.e. how many people will be misdiagnosed by bmi if it is used as a rough and ready measure of obesity to encourage GPs to target weight loss on a population level. Discussion of these types of issues needs to be better than sound-bite level and it’s likely that when GPs answer a question like this they are considering the role of measurement in their daily practice, and answering accordingly.
@sg
Everyone does, really? BMI can give an endomorph a “good” reading even if they are carrying a lot of abdominal fat, BMI can give a mesomorph a “bad” overweight reading even if their body fat is low. Ectomorphs can be given a “bad” underweight BMI reading despite being well-nourished. This has been known for a long time. Elite athletes are an extreme case, but it’s just the same for sedentary office workers.
BMI is a very broad brush – both the originator Quetelet and the reviver Keys (1972) specifically stated that the BMI was designed for population studies and was inappropriate for individual assessment. But it’s easy, so it gets misused.
Risk factor means just that. A factor that epidemiologically carries a risk of illness independent of other, known risk factors when the data is corrected for the co-occurrence of the two. The classic case of co-occurrence is actually the coffee story. Clearly associated with pancreatic cancer but once you correct for smoking the association disappears.
The bottom line is that obesity, defined in a way that captures those who are more than a little overweight, is an independent risk factor for diabetes, osteoarthritis and sleep apnoea. There is a clearly increased rate of the cardiovascular risk factors among those with increasing body fat but, I agree, disentangling chicken from egg in that situation is difficult. What is clear is that obesity is, in a significant group, a necessary cause for their diabetes. In this group weight loss is curative.
Now, I personally take a very restrictive view of health and disease. I look at hypertension, hypercholesterolaemia and smoking as risks to one’s health rather than health problems in themselves. I view health as the absence of disease, it ends up being much less pejorative and messy way to look at it. From this standpoint the statement that “obese people can be healthy” is self-evidently true. If the argument is that health includes the absence of meaningful risks and the sense of feeling well, as it must if hypertension and smoking become health problems, to exclude obesity from the category of health problems is not rational, it is definitional and political.
Disease is not inevitable in obesity but it is certainly more likely. If that is sufficient to define ill health, as many modern authors on this subject feel it to be, then the answers are reasonable. Term definition problem, as previously noted.
Thanks for the detailed response, Dr S. I certainly agree that evidence shows weight loss to be curative for obese people already diagnosed with Type 2 diabetes.
I can see your point on the absence of meaningful risks, but “the sense of feeling well” seems to suffer from a term definition problem too, surely? There are plenty of active obese people who feel fit and well, so where do they lie on the “health problem” chart?
Yup. The current trend to include sense of well being and whole pile of other things in “health”, to turn it into wellbeing, leads to a whole series of these kinds of problems. I like to keep health nice and narrow, saves me poking my nose in more of other peoples’ business than already do.
sorry “…MORE than I already do”
Obesity thrown around willy nilly these days.
BMI is a useful tool as is the waist measurement one thats increasing used as a rule of thumb. They are probably best called indicators or proxies than measurements of obesity.
Dr S – I’m no inclined to the “absence of disease” view. I think it leads to an idealalised state of being that doesn’t exist in many people and it leads to thinking of anyone who is sick or disabled as different or the other.
I see health as the successful management of whatever diseases or disabilities one has so that they don’t have more impact than is unavoidable.
Most people actually have some ill health, many need to wear glasses, people have deteriorating hearing, some have a back back, people have genetic predisposition to certain illnesses , some high cholesterol isn’t due to diet, many “bad hearts” aren’t due to lifestyle, not all diabeties can be prevented, bowel cancer can’t be prevented, cataracts can’t be prevented, and so on, it is rare to see a person who doesn’t have some less than perfect health.
The successful management of whatever degree of less than perfect health we all have is influenced mainly by access to services, educational level and financial security.
There are plenty of people with cancer that feel fit and well. Feeling fit and well doesn’t necessarily mean you are.
I am on an epic weight loss regime. Ultra-disciplined. Daily regime, give or take a 1-200kcal of exercise and a meal or two off from the diet every week when i socialise with friends:
8x cups of black coffee 8kcals
mother energy drink 208kcals
Celery 6x stalks 62cals
Apples large raw 116cals
tuna in lite oil x2 466kcals
corn, raw, small 62kcals
spinach raw 2x cups 14kcals
corn wraps x6 389kcals
Total consumption 1325kcals
Base metabolic rate -2521kcals
Activity level desk job -504kcals
Exercise -429kcals
Net kilocalories -2129kcals
Weight/gained lost -304g
Definitions seem to be the tricky thing here. Terms such as ‘health’, ‘well-being’ and ‘obesity’ seem difficult to define. I’m wondering that if the BMI is a really dodgy measurement, what are people talking about when they talk abour ‘obesity’. Does it have any meaning outside the BMI scale? Without that scale is it just a subjective term?
tigtog:
this is what i was referring to in my second paragraph. Doctors shouldn’t use BMI to assess obesity in the consultation, but as a screening tool its validity is assessed by different standards.
Your talk of ectomorphs and endomorphs makes me think of Traveller:2300 …
Word, desipis. If I’d been rung up and asked those questions by some survey-taking call centre person I would have quibbled about the wording of every single one.
In whch case, PC, you would have achieved your aim. You’d be put on their internal “Do not call: difficult arsehole” register.
Oooh, where do I sign?
Glen, assuming you are serious and have a lot of weight to lose, with an amount targeted and working within a time frame, why not just fast and drink at least eight glasses of water a day? It’s easy after the first day or so.
Weight loss apart it’s the best health kick I’ve come across after a lifetime of addiction to food generally, bread, jam and cheese in particular, fish and chips and chocolate, all the usual deprived childhood habits, frantically interspersed with all the usual diet fads. These all worked for a while but then bad habits either crept in by stealth or crashed back in with crazy cravings.
When I discovered that a medically supervised fast could rapidly relieve me of arthritis and depression at the same as rejuvenate me I set about reading the recommended literature and have never been on a diet since. Once I’d stopped eating and discovered how it felt to occupy a chemical and additive free body I began to explore organic foods and ultimately have come to a balanced diet.
I’m in better health than ever. Great feeling at my age. I bless that GP, unusual and alternative that he was, and extraordinarily difficult to get an appointment with!
I’m still an addict by the way! Just can’t kick the chocolate and the coffee! Well, food generally, with every meal enjoyed – organically produced cheeses, fish and some meat, but always accompanied by home grown vegetables and salads. I love wine too, though addiction can’t take hold here since I fall asleep after two glasses.
And water! Plenty of it, from waking till late afternoon. Not too late though – as FXH says we all have some problem or other. Still, an aging bladder is manageable, and occasionally ‘wetting myself’ seems a small price to pay for a good meal out with friends and plenty of laughter.
Great advice PatriciaWA, water is the essence of life. And the only other “rule” for those of us of a certain age is nothing after 7 pm – advice from Oprah. And I am now on my third G&T. Malaria you know.