Well, that's a good advice in theory, but did you notice how many doctors, dietitians and nutritionists have contradicting points of view?
Most doctors are essentially statisticians doing something like this:
1) Formulate a list of patient symptoms, ensuring credibility (e.g. are you lying/hiding/unaware-of something?).
2) Match those up with whatever diagnosis is statistically most likely.
3) Take "medicine X" and see what happens.
4) Cured? If not, go to step 2, repeat.
Step 2 can be subjective, especially if there are several likely causes. This can lead to different doctors giving different diagnosis. The more times a doctor has seen the same problem, the more likely he/she will be correct the first time. Specialists come in handy here, gathering lots of experience regarding only specific conditions.
For rare diseases, hard to diagnose, or those which aren't fully understood, repeating steps #2 - #4 is going to be more likely. This is where you'll find the greatest differences of "opinion".
Step #1 can be repeated too if conditions change, of course.
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Regarding dietitians/nutritionists, I'm not sure how they work. I'd imagine most of their disagreements come from studies contradicting one another. Results of studies can be questioned as well.
There is some overlap with the statistical nature of doctors, though. Pinpointing food allergies/intolerances requires eliminating foods, one-at-a-time, from your diet and seeing what happens. I'm sure there are blood tests which can be done too.
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In general though, it's not wise to discredit professionals just because they may disagree on certain things in their field. Unless the field is fully understood (I'm not aware of one which is!), you'll see that.
Perhaps I should rephrase my advice:
What's the best advice to take? That from "multiple" doctors, dietitians, or nutritionists. Not some yahoos on the internet.
A second or third opinion reduces the likelihood of errors, while limiting received advice only from those educated and qualified to give it.
I'd say that the field is quite poorly understood. Here's an article (long!) that kind of sums it up.
http://www.nytimes.com/2007/01/28/magazine/28nutritionism.t....
What's the best advice to take? That from "multiple" doctors, dietitians, or nutritionists. Not some yahoos on the internet.
A second or third opinion reduces the likelihood of errors, while limiting received advice only from those educated and qualified to give it.
I found out that even after that, I'm tempted to try and do some of my own research, and then apply the advice to myself and see how well it works ...
While I do like some of the messages and ideas Michael Pollan (author of linked article, plus Food Inc.) is promoting, I always take him with a grain of skepticism. He's correct sometimes, and incorrect or questionable others. A common symptom of someone who's not a doctor or researcher in the field.
I personally classify him in the same arena as Michael Moore. Not to be ignored, but instead to be questioned for every made claim, requiring non-cherry picked studies and scientific research to back him up.
Here's what I do: I eat whenever I feel like it, whatever I feel like, as much as I feel like. But when I'm full, I stop.
For breakfast this can be:
- yogurt with banana and jam and sugar
- slices of bread with cheese and tomato and olive oil heated in the oven
- a bar of chocolate
- bread with boiled egg and mayonnaise
- bread with butter and cheese/jam/other
- nothing
- pizza left over from the previous night (home cooked of course ;)
- any other left overs
- fruit
- when I'm hungry, a bowl of pasta
Don't obsess over what you eat until there is clear evidence. Eat things you like to eat.
What I personally would be worried about is the long-term effects. Unfortunately, these would be very hard to pinpoint as it would be virtually impossible to get enough people to volunteer eating a certain diet, without much fluctuation, for some 30 years or so. And even if such a study would happen, the endless argument would start: "But the diet A contained X, and diet B lacked Y, so obviously we can conclude ..." etc.
Not overeating (and undereating) is like 10 times more important than what you eat, as long as you get enough of all the nutrients you need.
This may or may not be true, and also we could argue about the factor forever. I would say it's way less than 10, especially in the long-term, but I have no way to prove it of course.
Don't obsess over what you eat until there is clear evidence. Eat things you like to eat.
Well, there is the "classic" - "Nutrition and Physical Degeneration" by Weston Price. (Available online at http://journeytoforever.org/farm_library/price/pricetoc.html) He traveled around the world and watched what happened to primitive societies when they introduced western foods in their diets. I read it briefly, and he made an emphasis on dental health, but literally introduction of white flour, sugar, polished rice and canned food produced a huge drop in dental health.
Perhaps you don't need to force people to eat certain things. You can observe what they eat and how healthy they are. If you have a large enough sample set you may be able to reach some conclusions. The internet and recent developments on it like things like Facebook may help a lot: if people start recording what they eat on a regular basis you may be able to get a huge and diverse sample quite easily.
> I would say it's way less than 10, especially in the long-term, but I have no way to prove it of course.
From what I've seen I disagree. I know people who eat healthy according to conventional wisdom, but they eat too much. As a result they are fat and unhealthy. I also know people who get at least half of their calories from things that are considered unhealthy like sweets, coke and potato chips, but because they don't overeat they look healthy. Now it's true that body weight is not the only aspect of health, but it is a very big one and the only one that you can measure by looking at somebody...
> I read it briefly, and he made an emphasis on dental health, but literally introduction of white flour, sugar, polished rice and canned food produced a huge drop in dental health.
It's an interesting study but this is not surprising, since bacteria love these things too. Fortunately we have toothbrushes.
That said the study is highly biased. The "native" people are always laughing in the photos and the "modernized" people are looking sad.
But this doesn't explain away the order-of-magnitude differences in dental health Price found everywhere he went between people living on traditional diets (who typically didn't have toothbrushes, either) and those living on processed diets.
Have his findings been independently verified? Especially his claims that the bone structure is better in the individuals on native food, for which he provides almost no evidence.