Science and Pseudoscience in Adult Nutrition Research and Practice
csicop.org
csicop.org
One of the problems in the field is summed here> "Why are certain long-term epidemiology/observation studies (EOS) continued in spite of the persistent publication of pseudoscience from these studies?"
Those type of studies are why they keep flipping on eggs. It's oxidized cholesterol (and saturated fat) which helps along heart disease, not the generic form. In fact, the body makes both if you don't eat enough. [1][2] Are our bodies trying to kill us?
"there is no convincing comparative outcome evidence (as I defined above) that common foodstuffs, e.g., saturated fats like butter, rapidly absorbed carbohydrates like white rice and potatoes, or animal proteins, are especially helpful or harmful."
The body prefers saturated fat as a fuel source. Body fat is mostly saturated. When you burn fat your running on "artery clogging" saturated fat. Secondly it likes glucose. It converts all carbs sources to glucose then glycogen. But when you overload calories (from say, rice), the body trans-saturates it to palmitic acid, a saturated fat. [3]
Hi-GI foods, like rice and potatoes, turn to glycogen quicker. Supposedly high-GI = bad. But I think the better theory is high-GI = bad, given qualifiers x and y.
[1] http://en.wikipedia.org/wiki/Lipogenesis
What is one to do?
"BMI between 20-25"
"only follow nutritional advice if proven to be safe and effective."
"Practice moderation in nutritional matters"
"ingest enough vitamins and minerals, especially vitamins B-12 and D"
Kudos for tearing down modern nutritional research. However, the author seems to end up making the case that there is nothing we should do to improve our diet- that we must sit and wait decades for things to be proven.
If you don't have good enough modern research one idea is to look to history, to examine traditions and see if there is value in them. Here is one example of someone doing that. http://journeytoforever.org/farm_library/price/pricetoc.html
We are in love with numbers, and we think that we can just count the calories that go into our bodies and that is the secret to becoming skinnier (replace "calories" with "carbs" or any other measurement for the latest diet trend). The BMI is another (albeit much saner) manifestation of this desire to have magic numbers.
We're also enamoured with single-focus solutions: eat less tortillas and get fit, eat a stalk of celery every two hours, chug a glass of water before a meal, whatever the magazine rack at the grocery store tells us.
I am of the opinion that this is all badly misguided, especially because it needn't be that complicated. Eat on a regular schedule, in portions that leave you full but not satiated. Try to buy more raw food products and less highly-processed stuff. Include different types of food in each meal. Exercise regularly (there really is no substitute for this). Set your goals with yardsticks like cardiovascular endurance (for the layman, "can I jog up a flight of stairs without gasping?") instead of trying to lose x number of pounds in a week.
So no, I can't give you an exact answer. It will probably be centuries before nutritional science can do so, if ever. But I firmly believe that we can make ourselves a lot healthier by taking some simple steps to compensate for the fact that our modern lives do not follow the patterns that our bodies evolved to cope with.
I don't have references on hand, but I believe there's a fair amount of accepted research that shows that we eat far more meat (and probably dairy) than is good for us - some meat gives protein and other good things, but you go too far and your body starts processing all the fats and whatnot in unhealthy ways. The evolutionary standpoint certainly supports this - we evolved as primarily hunter-gatherers who would manage to kill an antelope once every two weeks or something. Agriculture changed our diets significantly, and not necessarily for the healthier (an interesting writer on this subject is Jared Diamond).
A target window of 26-41 pounds doesn't seem terribly unreasonable, so long as one doesn't blindly assume that merely being within the range is healthy.
I'd certainly prefer a body fat target, if it's supported by the research. (Perhaps a BFI? I'm certainly curious as to which denominator is the most representative of biological function, if not health).