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The Obesity Epidemic — Is Medicine Scientific?
An anonymous reader writes "An award-winning science author, Gary Taubes, has written a book that pans the medical community's treatment of the obesity epidemic. What is interesting is that it looks like the medical community is behaving in a very unscientific manner. Taubes points out that the current medical orthodoxy — that consuming fat makes you fat and exercise makes you thin — has no basis in research. In fact, all the available research points in quite another, and more traditional, direction. Here's the (excellent) podcast of an interview with Taubes on CBC's 'Quirks and Quarks.' So, has medicine become a non-science? Is it mostly a non-science? Somewhat?"
When it comes to the current thinking on nutrition, there is a definite point to what he's saying.
But to say that Exercise has no effect on weight loss is just plain wrong. Exercise changes the way your body processes the food you put into it (or, more accurately, your body adapts to the amount of exercise that you get). Building muscle causes you to require more calories in your diet to support that muscle. And building stamina causes you to burn a lot of calories in the process. And if you want to venture into the unscientific realm, consistent exercise helps to stabilize your mood and makes you less prone to food cravings (the cravings for sugary foods and for fatty foods are based in imbalances in Serotonin and Dopamine levels).
There is a dire need to re-examine everything we know about a healthy diet. People get so worked up about things like trans fats while completely ignoring the elephant in the room (high-fructose corn syrup). Everyone I know who's given up corn syrup, to the extent that it's possible in the US, has lost a minimum of 10 lbs.
But to suggest that exercise isn't a vital part of a healthy lifestyle is wrong, and potentially very dangerous.
"Don't blame me, I voted for Kodos!"
I lost 25 pounds after I simply cut out bread, potatoes, and sugar from my diet.
In the mean time, I added a gallon of olive oil every 60 days and a pint of cream a week.
Tho fit already (sports twice a week, regular walking and exercise) I started developing diabetes (of course my mom and grandparents had it so I'm kinda doomed there). Despite cutting out enormous amounts of carbs and sugars (I was previously drinking 1,000 calories of soda a day), I continue to slide in the bad direction on my blood sugar. It's not diabetic yet but it is just a matter of time.
My diet consists of large amounts of vegetables, meat courses, almost no grains (2-3 ounces a day tops).
I think people have different needs based on their genetic history.
I agree that a lot of "science" these days is opinion, hysteria, or someone's hidden agenda.
She was like chocolate when she drank... semi-sweet at first and then increasingly bitter.
He makes the extraordinary claim that Official Nutrition has been getting it wrong for the last 40 years. However, he provides and discusses a solid body of relevant and eminently respectable (Lancet, JAMA, NEJM, etc..) citations to support his claim. Color me 95% convinced.
He notes that the application of the first law of thermodynamics (the slogan is "A Calorie is A Calorie") to a homeostatic dissipative system like the human body is beyond simplistic. It is simply wrong.
The core of his thesis is that a cellular-level metabolic disorder caused over time by consumption of concentrated and rapidly available carbohydrates, and the insulin spikes they provoke, is the cause not only of obesity but also of type II diabetes. Briefly, fat cells become too good at extracting glucose from the blood and storing it. This results in cellular-level semi-starvation in other body tissues, expressed at the organismic level by eating more and exercising less.
He depicts the high level of investment in the competing "gluttony & sloth" model of obesity which exists in our medical establishment and in our culture. Indeed, from his portrayal this viewpoint is very close to being an ideology rather than a theory, in that dissenters are cast into outer darkness rather than refuted.
He discusses the personalities and politics involved in the alleged disastrous wrong turn, and points up some interesting coincidences involving what research gets funded, and what research doesn't get funded, by for example sugar producers.
I'm intentionally being very brief. If you have a personal stake, read this book and form your own conclusions.
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phunctor
The recommended advice of replacing fats with carbohydrates was repeated so often and so forcefully by everyone, that it's now printed on the back of almost every box of food in the country, in the form of the "USDA food pyramid". It was so often repeated that when I was a child (in the 1970s) things like wonder bread with a bit of margarine were considered health foods (lots of carbs, no saturated fat).
I had always assumed that the medical community had done large-scale long-term studies demonstrating that such a diet led to an increase in lifespan, a reduction in disease, and a loss of unhealthy pounds. Apparently, such studies were never done.
But then the massive Harvard Nurses Heatlh Study was performed, ending in the mid-1990s. In that study, researchers followed 40,000 nurses for decades, in what was the largest and most comprehensive study on human nutrition ever. The study found that replacing fats with carbohydrates had absolutely no effect on longevity or disease. Furthermore, replacing butter with margarine (the standard dietary advice for decades) led to no benefit either. IIRC, the only nurses who lived longer and had less disease were those who ate nutrient-dense monounsaturated fats like almonds and cashews.
As a result of the Harvard Nurses Health Study, researchers in nutrition quietly dropped their assumptions about dietary fats causing disease.
I still can't believe it. The standard dietary advice from 1960 to 1990 must have been the single largest pseudoscientific load of crap in modern history. What a colossal embarrassment. If the USDA publicly admits that it was mistaken then it will be a long time before people trust it again.
My girlfriend happens to be a doctor, and currently works in a 'obesity clinic', and she is going for a PhD in public health, with a focus on obesity, and she left me with the impression that:
- Real medicine never was a 'real' science. It's absolutely shocking how many publications, treatments and diagnosis are based purely on 'gut feelings', or incoherent theories. Just pull up any statistics on malpractices, and be shocked. No other 'science' could get away with so many errors, after such a long time of experimenting. This happens in part because medicine is a rather unique applied science: there're a lot of psychological factors, and incredible amount of measuring errors, a gigantic level of complexity and tons of historic 'baggage' that doctors have to face every day.
- Medicine is getting a lot better in this aspect - there seems to be a relatively new way of thinking (in the medical community, at least) called "Evidence based medicine", which, if i understood correctly, could be basically summed up as applying scientific principals to the medical processes
- Obesity in specific is extremely complex. Almost everything you do has some influence on you body-weight and composition. Of course the laws of thermodynamics apply to human beings, too, but there are a gazillion factors that influence just how exactly the body deals with excessive calorie intake, or lack thereof, ranging from genetical to psychological and social factors. Just a basic example would be that if you simply stop eating for a week, you usually lose LESS weight compared to if you start 'snacking' all the time, eating 5 little meals a day (basic theory behind this sems to be that the body switches to 'emergency mode' if there's no food around, trying to save as may energy reserves as it can)
- Most theories seem to me to be a wild mixture of anecdotal observations mixed with biochemistry, somehow resembling Freudian theories - they are coherent in them selves, but lack a level of 'scientific interconection' to other knowledges. So it's quite common for a specific theory in obesity to me contradictory to a theory of e.g. neuroscience. As long as both theories "kind of" work, it doesn't seem to be a top priority to resolve that discrepancy (in contrast to what i have observed in 'hard sciences'). AS far as I can tell, thee's no real proof or reason why Whiskey shouldn't be as bad as Vodka in a diet, yet (here, at least) it's common knowledge that whiskey's ok, but vodka will make you fat - and as long as this works, it doesnt matter that much why this happens, or if it happens at all.