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Meta-Research Debunks Medical Study Findings
jenningsthecat writes "From The Atlantic comes the story of John Ioannidis and his team of meta-researchers, who have studied the overall state of medical research and found it dangerously and widely lacking in trustworthiness. Even after filtering out the journalistic frippery and hyperbole, the story is pretty disturbing. Some points made in the article: even the most respected, widely accepted, peer-reviewed medical studies are all-too-often deeply flawed or outright wrong; when an error is brought to light and the conclusions publicly refuted, the erroneous conclusions often persist and are cited as valid for years, or even decades; scientists and researchers themselves regard peer review as providing 'only a minimal assurance of quality'; and these shortcomings apply to medical research across the board, not just to blatantly self-serving pharmaceutical industry studies. The article concludes by saying, 'Science is a noble endeavor, but it's also a low-yield endeavor ... I'm not sure that more than a very small percentage of medical research is ever likely to lead to major improvements in clinical outcomes and quality of life.' I've always been somewhat suspicious of research findings, but before this article I had no idea just how prevalent untrustworthy results were."
That's one of my favorites... or the presumption that eating fat makes you fat.
People seriously do not understand nutrition or how diet and exercise work. Lately, I have been doing an kind of experiment for the people around me. First, for about a month or more, I started riding my bicycle to work. I was working it hard. Then, after it was established that I had been riding my bike for at least a month, I started on a low-carb diet. Within two weeks people started to notice the weight loss. Some still wanted to believe it was the bicycle riding. I had to lay it out to them what the deal was. Exercise burns carbs and then fat. Trouble is, the carbs we take in our daily diet still outnumbers that which I burn from riding 10 miles each day. It is only after I limited the intake of carbs that a difference could be made and observed.
Here's why I did it like this:
People don't listen for more than a few sentences and are especially resistant when the information conflicts with what they think they know. Eating fatty meats is contrary to their beliefs about what a weight loss program should contain so they simply refused to accept it. Hell, even many doctors don't yet fully acknowledge that making your body burn fat will reduce cholesterol. (Hello? cholesterol is fat floating in the blood!)
Having lost almost 30 lbs in a 6 week period has been noticed by all and the evidence is right in front of their faces. I lost the weight, and this is what I have been eating.
"Reduce the primary source of fuel so that it will use the secondary source of fuel. It's really that simple."
No, it isn't.
The (almost) only direct source of "fuel" for the organism is sugar (glucose), full stop*1.
Anything else the body ingests or stores has to be reduced to sugar (usually by means of the krebs cycle) prior to be "burned".
While this is a very basic simplification, this, and the fact that the blood can carry a limited level of sugar at a time, is what explains, at a whole body level, everything else.
Like...:
* Since you can only burn sugar, sugar-equivalent contents is all that counts for weight imballance (of course, within limits: you can't just stop your ingestion of, say, oligoelements). That's what we really talk about when we talk about food calories.
* If you directly eat sugar (glucose), the sugar will be immediatly burn, but since your blood has limited sugar carriage capacity, you should be continously eating like a hummingbird to sustain that, so you usually just can't eat sugar in excess.
* If you eat carbs, they'll be transformed into sugar and burned. Any carb in excess will be stored as glucogen in your liver. If there's still carbs in excess once your liver can't hold any more glucogen, it will be transformed into fat and stored under your skin.
* If you eat fat, it will be transformed into sugar and burned. Any fat in excess will be stored under your skin unless you are so low in glucogen (which usually won't happen) that part of the fat is transformed into glucogen and stored in the liver.
* If you eat proteins, they'll be used for structural development (like muscle mass). Usually, anything in excess will be trashed away, unless you are very low in sugar, carbs and fat intake (it usually doesn't happen) in which case, it will be uneffitiently transformed into sugar and then, burned.
* To explain for long term weigth, all that's needed is accounting for your ballance between ingested calories and burned calories: if you eat more calories than you burn, your weight increases; if you eat less, you lose weight.
For a practical example:
If you eat less carbs and more fat to the point that daily calories stay the same, You Will Not Lose Weight (but in the long run you will develop cardiovascular illness).
If you eat less carbs and more proteins to the point that daily calories stay the same, You Will Not Lose Weight (but in the long run you will destroy your liver).
Given the ballance between ingress and burn, you can obviously go two (complimentary) routes:
1) Eat less calories. Sustaining a varied and ballanced diet, only eating less, is the way any sensible nutritionist will suggest since it's the easiest to do properly long term and the easiest to lead to you changing your habits. But as long as you stay to the First Principle "eat less calories", and within sensible limits, you will get it right.
2) Burn more calories. That's where exercise and rising your basal metabolism come into account. Aerobic exercise is an obvious recomendation, but other less obvious things like lowering your home thermostat 3~4 degrees in winter will have it's effect too. Again, it's not what you do, but what you achieve with regards of burned calories.
Everything else about diets is about making acceptable for you to eat less calories/burn more calories (like, unless you are a kind of iron-man you won't have the will for strengh training like weight lifting unless you go heavy on sugars; the same with aerobics, like long distance running or bycicling unless you go heavy on carbohidrates, or you'll probably break your diet if you are just told "eat exactly the same as you did, only on third the quantities", so you are offered a diet with much less calories but about the same or even more volume so you feel satiated, or you'll probably will abandon a diet if you don't see fast results at least at the beginning, so you are offered a diet very low in calories for the first weeks so you fastly see your efforts are