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The reason why healthy things taste bad

  1. May 1, 2012 #1
    Have you ever wondered why what tastes good is often not healthy despite the fact that from evolutionary point of view the whole purpose of taste is to get you to eat what is healthy? I found an interesting explanation that probably none of you have thought of. On a grand scheme of things, what tastes better IS healthier:

    1. Salad tastes better than dirt, and salad is healthier than dirt
    2. Cookies also taste better than dirt and they, too, are healthier than dirt

    Now, since the VAST MAJORITY of food available is dirt, ON A GRAND SCHEME OF THINGS the healthy things DO taste better than unhealthy ones. The problem is that correlation is not perfect. So one small "imperfection" in correlation is

    3. Cookies taste better than salad BUT salad is healthier than cookies

    Now, item 3 is VERY SMALL compared to 1 and 2. Just think about it: it is A LOT more unpleasant to eat dirt than any unpleasantness one would have eating salad. And it is A LOT worse to your health to eat dirt than it would be eating cookies,

    But as "small" imperfection as it might be, the "imperfection" is all you are going to pay attention to. After all, since dirt is neither healthy nor tastes good, the dirt simply would never enter your mind. In order for item X to enter your mind, item X has to EITHER be healthy OR taste good or both. And here is what makes healthy food taste bad:

    4. If item X is healthy (e.g. salad), it has a "qualification" to "enter human consideration" DESPITE bad taste
    5. If item X tastes good (e.g. cookie) it has a "qualification" to "enter human consideration" DESPITE being unhealthy

    This, together with the fact that

    6. Most things taste bad and most things are unhealthy
    7. Most things (e.g. dirt) never enters human consideration
    8. The pattern exemplified by 1 and 2 is not perfect

    provides an excellent statistical explanation why healthy things taste bad and unhealthy things taste good.

    Lets put it this way: items 4 and 7 imply that

    4, 7 ==> If an item X tastes bad and it enters human consideration, it MUST be healthy

    Items 5 and 7 on the other hand imply that

    5, 7 ==> If an item X is unhealthy and it enters human consideration, it MUST taste good

    Finally, item 6 imply that

    6 ==> Things that are BOTH healthy AND taste good are EVEN LESS common than things that are ONLY one OR the other (I mean, two "rare" things co-existing at the same time is even more rare)

    (4, 7 ==>), (5, 7 ==>) and (6 ==>) above imply that AMONG THINGS THAT ENTER HUMAN CONSIDERATION there is "opposite correlation" between being healthy and tasting good
     
    Last edited: May 1, 2012
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  3. May 1, 2012 #2

    Office_Shredder

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    This kind of argument could work if the properties 'tastes good' and 'good for you' are independent, but I don't think they are
     
  4. May 1, 2012 #3

    D H

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    That is a nonsense comparison. The rest of your post fails because you are reasoning from nonsense.

    There's a simple explanation for why some people are attracted to foods that we now deem to be unhealthy. Such cravings for supposedly unhealthy foods were not always unhealthy. They were a local optimum that maximized the likelihood to bear children and have those children live long enough to have children of their own.

    The ability to eat an optimal diet is very, very recent. An optimal diet is a luxury. We have not had enough time to evolve tastes that are aligned with this luxury. Our forbears instead had to live in a world where the diet was highly suboptimal, marked with occasional spates of severe shortages of food. The best way to live through those shortages was to put on weight before they hit. The best way to do that: carbs. We crave sugar because they helped our forbears survive. This was particularly so with hunter-gatherers living in marginal areas, and still is. Peoples from such backgrounds who are suddenly thrust into the modern world have significant problems with obesity.
     
  5. May 1, 2012 #4
    If an argument works for two quantities that are independent, it would also work for "weak enough dependence" (after all, an independence is a limit of weak dependence). So my argument in this article was that, while dependence strong (see dirt example) it is not strong enough; thus, in the context of cookies vs salad the dependence is "weak enough" to produce the result consistent with independence.
     
  6. May 1, 2012 #5
    The explanation that you gave and the one I gave can both be right. After all, anything "statistical" might in fact have "physical" explanation that is simply beyond our knowledge. So when I made a "statistical" argument about "correlation not being perfect" this implies that "some 'unknown' physical factor will come along and mess it up". Well, in your reply, you have specified the "unknown factor" (namely, that in the past it was more efficient to eat sugar to store calories for starvation which is not the case any more). But, on a statistical side, I can still say "even if we didn't know what you just said, we expected that SOMETHING would come alone, anyway for statistical reasons; you simply told us what that 'something' is".
     
  7. May 1, 2012 #6

    turbo

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    Thank you. Those of us with parents who managed to survive the Great Depression know what you're talking about. My mother and her sister used to take us kids (girls kicking and screaming about having to "work") picking berries, wild fruit, etc, and that was huge. We didn't just go pick a few pots and pans of berries or apples and gorge on shortcake-type treats. We cleaned and bagged those foods and froze them in the big chest freezer. Next winter, mom could head out there and get stuff to make a pie or maybe a little batch of blueberry muffins.

    Fruit (aside from apples) was very expensive here in the 50s in the winter. My favorite great-uncle (I didn't meet him until he was out of the TB sanitarium) went to work as a butler for a wealthy old gentleman in CT and they wintered in Florida. Every Christmas season, he would ship us a crate of mixed citrus, and I was so glad to see that box show up. Grapefruit, oranges, lemons, limes, kumquats... My parents could never have afforded that. What a treat!
     
  8. May 1, 2012 #7

    bobze

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    Spot on. And don't forget fats. Fatty food in a pre-industrial environment is great, because it is rare and fats are the ultimate survival food. Why are those hamburgers and marblized steaks so good? Because evolutionary speaking, we ought to eat fats when we can get a hold of them. The problem now is, they are easy and abundant for anyone and everyone.

    Minor note, the best way to put on weight before a shortage is fats (not carbs). Carbs get stored in the body as glycogen, which doesn't last all that long in the setting of things like starvation. Fats which can provide much more energy through metabolism are better for long term storage (think why bears gorge on fish and moths before winter!).

    That's not say carbs aren't important though and it makes sense that we would have an inbuilt evolutionary craving for them. The problem with fat is it takes a long time to metabolize, compared to say carbs. This becomes especially important for day to day activities and being able to use muscle. Which uses creatine phosphate first, but your supply runs out very quickly. After that its glycogen→ glucose and anaerobic metabolism when you are working your muscles. So eating sweet foods, high in those simple carbs would have been important for our ancestors--Especially say, when a lion might be chasing you later that afternoon.

    Fats are good for making up the "debt" your muscles acquire during hard work (again because their metabolism is slow) and for slow/steady sources of energy.
     
  9. May 1, 2012 #8
    Without reiterating the obvious id like to point out that many kids love to eat dirt, and this is a positive adaption that helps there immune system develop. Adults also to some extent enjoy the flavor of dirt as mushrooms are often described by there "earthy" flavors.
     
  10. May 2, 2012 #9

    Bacle2

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    But I don't know to what extent evolution can explain all of this successfully; one definition of addiction is that of craving things that are not good for you, like, say, crack, or regular cigarretes. I don't see how this could be explained thru evolution.

    Re the OP, I think one should exclude dirt as a food. I think food should be a subset of the set of things the body can break down (using enzymes; in digestion in general) into nutrients that can be absorbed by the body. I don't think the body can break down dirt.
     
  11. May 2, 2012 #10

    OmCheeto

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    Awesome question.

    Awesome answers.

    :smile:
     
  12. May 2, 2012 #11

    chemisttree

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    I hope you're not suggesting that simple sugars or any digestable carbs aren't stored as fat!
     
  13. May 2, 2012 #12

    turbo

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    BTW, healthy things don't necessarily taste bad. Smell and taste are inextricably tied. If you have stuff like broccoli or cabbage that have been stored for a while (not out-of-the-garden fresh) you can get turned off by the odors, even if you like both vegetables. I love both of them, but I have to use them when they are fresh... Maybe it's just me.
     
  14. May 2, 2012 #13

    Pythagorean

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    As has already been explained that evolution hasn't caught up to our very recent age of industry where we can manufacture crack and cigarettes. But also remember that people can reproduce just fine while being addicted to crack and cigarettes, and society will take care of their kids if they don't, so there's not a huge selective pressure on those addictions. Miserable and unhealthy doesn't automatically mean that you're not fit for reproduction.
     
  15. May 2, 2012 #14

    D H

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    It's not just you. You probably have one copy each of the sensitive and insensitive versions of the hTAS2R38 gene. People with two copies of the sensitive version typically can't stand broccoli, watercress, mustard greens, turnip, rutabaga and horseradish. There is a statistically significant connection between the gene and dislike of those six vegetables. There's a good reason for this. People who don't get enough iodine are at increased risk of thyroid insufficiency. The glucosinolates in broccoli etc. inhibit iodine uptake. This makes people who don't get enough iodine and who eat those vegetables be at a markedly increased risk of thyroid insufficiency -- and this in turn makes it advantageous to be able to taste (and avoid) foods that contain those toxins.

    I love those vegetables. Most of my ancestors came from areas where seafood was a huge part of the diet. The sensitive version of the gene isn't advantageous in such areas (and arguably is disadvantageous).
     
  16. May 3, 2012 #15

    bobze

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    No I didn't say that. Again we're talking about an evolutionary basis for something as well, not our modern society. Sure carbs can be converted to fatty acids if you eat enough of them (like in our modern society where they are in abundance), but think about in a pre-industrial/modern world--Or again, look at other animals that don't have the luxury of human food production.

    Fats are the best way to store fats and build up long term energy stores, they are most easily converted to fatty acids as well (already being fat and all). Carbs and protein, when eaten in abundance can also build fat stores, but again in 10,000 BC that "sugar craving" was probably better served for keeping glycogen levels maintained and less to do with fat storage.
     
  17. May 3, 2012 #16
    Ahem.

    Most people here have already provided valuable input, but allow me to chime in and say that if you think healthy things taste bad, this is most likely a matter of being conditioned to those horrible substances people tend to call 'food'. I've had the luck of having parents who were very strict about eating natural foods, so most unhealthy 'foods' actually disgust me.
     
  18. May 3, 2012 #17

    Monique

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    Except boterkoek :biggrin:
     
  19. May 3, 2012 #18
    Shush, you. :tongue: It's natural since I made it myself from natural ingredients. :biggrin:

    But, on a more serious note, I was talking mostly about the foods with HFCS and, well, stuff like that. As far as I'm aware, my boterkoek contains no such things. :wink: Boterkoek is still unhealthy, of course.
     
  20. May 3, 2012 #19

    D H

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    Do you Dutch have any food that "puts hair on your chest?" Fish buried in the backyard with soap, a head of cabbage left to rot and ferment, oysters (not the kind that live in the sea), eyes and other interesting bits and pieces, stuff you don't want to know about stuffed into a tube, ...?
     
  21. May 3, 2012 #20
    Well, you can drink a big bottle of jenever, or eat a big slice of liver sausage with your toast. And of course oil balls are delicious, too. :biggrin: I can't think of anything too gross, though, but most likely I'm just used to the stuff I eat.

    (Protip: don't combine these foods.)
     
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