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This is also the reason that fields like nutrition science aren't generally all that useful if what you want to do something like offer diet advice. There are j

This is also the reason that fields like nutrition science aren't generally all that useful if what you want to do something like offer diet advice. There are just too many shifting pieces to offer a systematic explanation of what's going on, at least with the experimental limits we have right now. You can only track so many variables at once.

bertm 16y ago
This presents an interesting paradox though because at the end of the day a decision is required. Do I eat thing X or thing Y? And in what proportion? So when a set of things is not well understood but a decision is required, many non science strategies enter. So what can be done about this?
- scscsc 16y ago
  You listen to science and not to crackpots who pretend to do science. Note that most advice regarding nutrition appearing in newspapers/blogs is total crap (as opposed to science). If you can't distinguish science from crap (or can't be bothered to search for science) I would suggest you go with what seems reasonable to yourself.
  - stellar678 16y ago
    That's the whole point though - science so far can't give much useful advice on what to eat, the topic is just too complex. Science can give hedged explanations of what's been observed in relation to a particular nutrient, but that's a far shot from dietary advice. What seems to end up happening is "we've observed a correlation between saturated fat consumption and heart disease" makes it out of the science world and gets turned into "avoid saturated fat at all costs" (and buy our replacement products). Then years later we realize it's a lot more complicated than that.
    - scscsc 16y ago
      It was known at the time that correlation is not causation. That is a classic example of taking dietary advice from the incompetent.
- nazgulnarsil 16y ago
  you have to downgrade from induction to deduction. given the environment humans evolved in and what we know about primate digestive systems, what is unlikely to do me harm? answer: fruit, nuts, eggs. what is the biggest thing we do that monkeys don't? eat tons of processed grains. simple answer: decrease processed carb intake, replace with fruit (primate diets are often 50% fruit). since eating no grains isn't an option, eat the ones considered healthier: corn, beans, brown rice.
  - rue 16y ago
    And how long do monkeys live again? That is not to say it is a bad idea, just that you do not present any evidence that grains are somehow bad. In fact, without considering all the other variables, one could just as well argue that grains are fantastically good for humans.
    - Daniel_Newby 16y ago
      The archaeological and medical evidence (celiac disease) suggests that humans are not especially well adapted to eating cereal grains. That does not mean they are entirely bad, just that their hidden costs are relatively more likely to be whimsical and unpleasant.
      - rue 16y ago
        And what do widely present allergies to pea- and other nuts, peas, carrots, tomatoes, citrus fruit, fish or shellfish (among others) tell us?
        elblanco 16y ago
        Don't forget eggs, bananas, peaches (and relatives), onions, carrots, etc. (include most foods, yes I've known people with fantastically, life threatening, sensitive allergies to these foods). One of my favorites is the genetic differences over perception of the herb coriander. Some percentage of people hate it because it tastes like soap. While the rest don't taste any soapy taste at all and find it to be a pleasant seasoning. People often make the mistake of conflating "evolved diet=good for you" with "ready availability of foodstuffs". Chimps will also happily eat a pile of steak and a milkshake if you give it to them. Alaskan Salmon are fantastically good for us, but they don't exist at our evolutionary homestead. Some humans have consumed dairy for so long that they have developed lactose tolerance, and some eat such a high protein diet that large amounts of carbohydrates (refined or otherwise) leads to very high percentages of diabetes. IOW, not every human has the same genetic lineage, Coeliac disease is interesting for some variety of humans, but doesn't exist at all in other populations -- and even in the populations it does exist in, it has a pretty low frequency (generally less than 1% population in any area no matter the genetic predisposition of the population). Egg allergies (one of the cited foods in this thread as "evolution safe" are fantastically more common by comparison. It's the second most common childhood allergy in the U.S.
- marilyn 16y ago
  I want to say cheesey things like "The only thing certain is uncertainty" and talk about the pangs of Hamlet, but instead I'll offer this bit of advice from Colin Powell I recall from previous HN threads: Part I:"Use the formula P=40 to 70, in which P stands for the probability of success and the numbers indicate the percentage of information acquired." Part II:"Once the information is in the 40 to 70 range, go with your gut." From lesson #15 in this presentation about Colin Powell on Leadership (http://www.slideshare.net/guesta3e206/colin-powells-leadership-presentation http://www.slideshare.net/guesta3e206/colin-powells-leadersh...)
thribbler 16y ago
>systematic explanation Yes. Too many scientists aren't trying to explain things; rather they wander around looking for new correlations. There's an abundant supply of correlations wherever one looks.
- rbanffy 16y ago
  And the number of correlations grows exponentially with the already exponential growth of the amount of data they can analyze. It's been highlighted before we need better standards for what's meaningful and what's noise.
tensor 16y ago
This is absolutely incorrect. We know way more about good diet and the effect of nutrition than we used to. We do not know everything, but claiming that nutrition science is not useful is horribly wrong and misleading. If you are offering diet advice, you should absolutely make use of all that we do know: and that knowledge comes from nutrition science.
- stellar678 16y ago
  If our end goal is to offer everyday guides on what foods to eat, nutrition science has a really hard time offering anything useful. The predictions are necessarily minutely targeted at particular nutrients in isolated trials. It's really not possible to come up with a diet plan that replicates those isolated trials. I guess what I'm saying is that we don't (currently) have the capabilities to run studies big enough to examine the whole system in all its intricate pieces. You can do surveys - and I think they are probably the most broadly-useful current nutrition studies, because they give recommendations like "food-related disease is significantly lower in people who eat a mediterranean diet". That's an actionable prediction. As another counter-point to my argument, isolated experiments seem to work well in providing recommendations like suggesting to stay away from carcinogenic foods, etc...
  - Qz 16y ago
    We're not that good at telling people what they should eat, but we're pretty damn good at telling people what they should not eat.

bertm 16y ago

This presents an interesting paradox though because at the end of the day a decision is required. Do I eat thing X or thing Y? And in what proportion? So when a set of things is not well understood but a decision is required, many non science strategies enter. So what can be done about this?

scscsc 16y ago
You listen to science and not to crackpots who pretend to do science. Note that most advice regarding nutrition appearing in newspapers/blogs is total crap (as opposed to science). If you can't distinguish science from crap (or can't be bothered to search for science) I would suggest you go with what seems reasonable to yourself.
- stellar678 16y ago
  That's the whole point though - science so far can't give much useful advice on what to eat, the topic is just too complex. Science can give hedged explanations of what's been observed in relation to a particular nutrient, but that's a far shot from dietary advice. What seems to end up happening is "we've observed a correlation between saturated fat consumption and heart disease" makes it out of the science world and gets turned into "avoid saturated fat at all costs" (and buy our replacement products). Then years later we realize it's a lot more complicated than that.
  - scscsc 16y ago
    It was known at the time that correlation is not causation. That is a classic example of taking dietary advice from the incompetent.
nazgulnarsil 16y ago
you have to downgrade from induction to deduction. given the environment humans evolved in and what we know about primate digestive systems, what is unlikely to do me harm? answer: fruit, nuts, eggs. what is the biggest thing we do that monkeys don't? eat tons of processed grains. simple answer: decrease processed carb intake, replace with fruit (primate diets are often 50% fruit). since eating no grains isn't an option, eat the ones considered healthier: corn, beans, brown rice.
- rue 16y ago
  And how long do monkeys live again? That is not to say it is a bad idea, just that you do not present any evidence that grains are somehow bad. In fact, without considering all the other variables, one could just as well argue that grains are fantastically good for humans.
  - Daniel_Newby 16y ago
    The archaeological and medical evidence (celiac disease) suggests that humans are not especially well adapted to eating cereal grains. That does not mean they are entirely bad, just that their hidden costs are relatively more likely to be whimsical and unpleasant.
    - rue 16y ago
      And what do widely present allergies to pea- and other nuts, peas, carrots, tomatoes, citrus fruit, fish or shellfish (among others) tell us?
      - elblanco 16y ago
        Don't forget eggs, bananas, peaches (and relatives), onions, carrots, etc. (include most foods, yes I've known people with fantastically, life threatening, sensitive allergies to these foods). One of my favorites is the genetic differences over perception of the herb coriander. Some percentage of people hate it because it tastes like soap. While the rest don't taste any soapy taste at all and find it to be a pleasant seasoning. People often make the mistake of conflating "evolved diet=good for you" with "ready availability of foodstuffs". Chimps will also happily eat a pile of steak and a milkshake if you give it to them. Alaskan Salmon are fantastically good for us, but they don't exist at our evolutionary homestead. Some humans have consumed dairy for so long that they have developed lactose tolerance, and some eat such a high protein diet that large amounts of carbohydrates (refined or otherwise) leads to very high percentages of diabetes. IOW, not every human has the same genetic lineage, Coeliac disease is interesting for some variety of humans, but doesn't exist at all in other populations -- and even in the populations it does exist in, it has a pretty low frequency (generally less than 1% population in any area no matter the genetic predisposition of the population). Egg allergies (one of the cited foods in this thread as "evolution safe" are fantastically more common by comparison. It's the second most common childhood allergy in the U.S.
marilyn 16y ago
I want to say cheesey things like "The only thing certain is uncertainty" and talk about the pangs of Hamlet, but instead I'll offer this bit of advice from Colin Powell I recall from previous HN threads: Part I:"Use the formula P=40 to 70, in which P stands for the probability of success and the numbers indicate the percentage of information acquired." Part II:"Once the information is in the 40 to 70 range, go with your gut." From lesson #15 in this presentation about Colin Powell on Leadership (http://www.slideshare.net/guesta3e206/colin-powells-leadership-presentation http://www.slideshare.net/guesta3e206/colin-powells-leadersh...)

thribbler 16y ago

>systematic explanation Yes. Too many scientists aren't trying to explain things; rather they wander around looking for new correlations. There's an abundant supply of correlations wherever one looks.

rbanffy 16y ago
And the number of correlations grows exponentially with the already exponential growth of the amount of data they can analyze. It's been highlighted before we need better standards for what's meaningful and what's noise.

tensor 16y ago

This is absolutely incorrect. We know way more about good diet and the effect of nutrition than we used to. We do not know everything, but claiming that nutrition science is not useful is horribly wrong and misleading. If you are offering diet advice, you should absolutely make use of all that we do know: and that knowledge comes from nutrition science.

stellar678 16y ago
If our end goal is to offer everyday guides on what foods to eat, nutrition science has a really hard time offering anything useful. The predictions are necessarily minutely targeted at particular nutrients in isolated trials. It's really not possible to come up with a diet plan that replicates those isolated trials. I guess what I'm saying is that we don't (currently) have the capabilities to run studies big enough to examine the whole system in all its intricate pieces. You can do surveys - and I think they are probably the most broadly-useful current nutrition studies, because they give recommendations like "food-related disease is significantly lower in people who eat a mediterranean diet". That's an actionable prediction. As another counter-point to my argument, isolated experiments seem to work well in providing recommendations like suggesting to stay away from carcinogenic foods, etc...
- Qz 16y ago
  We're not that good at telling people what they should eat, but we're pretty damn good at telling people what they should not eat.