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Simple Question : Taste of Vegetables and Evolution.

  1. Dec 27, 2011 #1


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    Hi, All:

    Please forgive my ignorance of much (most ) of this topic--and biology in general.

    Basically, I'm puzzled as to why most people do not find the taste of vegetables
    naturally attractive, despite vegetables being benefitial, maybe even necessary
    for a healthy life.

    It seems in many respects that we find to be enjoyable/attractive things that are benefitials to us , while the converse is true, e.g., we find the smell of toxic substances ,
    to be unattractive , maybe feces being a good example; its smell helping keep us away from the slew of nastyness in it. Still, somehow, the taste of fruit seems to be naturally=attractive to most.

    What am I missing here?

  2. jcsd
  3. Dec 27, 2011 #2


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    I think you'd find the majority of humans do like the taste of vegetables, but vegetables weren't common and many did not even exist throughout history, especially in Europe. You mainly had grains, legumes, and root vegetables in antiquity.
  4. Dec 27, 2011 #3


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    But if most people like the taste of vegetables, why the hundreds of salad dressings out there? Fruits are more often, in my experience, eaten raw, i.e., without add-ons, than vegetables, i.e., no syrups , etc are added to fruit. Or, the popularity of fruit pies, but not of vegetable pies. It does seem that fruits appeal much more than vegetables, but I don't know if there is a proportionality between the appeal and the level of benefit of each.
    Maybe part of the issue is that many vegetables are not as easy to digest when raw, than when cooked. Or the fact that fruits are broken down more quickly than vegetables, so that they are more of a quick-fix.
  5. Dec 28, 2011 #4


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    This is like saying "if people like meat why the hundreds of curry sauces out there?" Human's like to have variety in their food which is a good thing, we also like certain flavours and we all have slightly different preferences thus there is huge potential for flavour modification. Lastly salads tend to be quite dry without some sort of dressing making them less enjoyable to eat, hence dressing.
  6. Dec 28, 2011 #5

    jim mcnamara

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    This is a review of how food prefrences are formed during pregnancy:

    It is adaptive, promotes survival, when small children are "pre-programmed" to like and eat available foods. It is also the source of differing tastes in food.

    Vegetables and spices have lots of interesting chemical compounds in them, many act to deter insects. see: http://onlinelibrary.wiley.com/doi/10.1111/j.1744-7909.2007.00395.x/pdf

    This lot of interesting chemcials, for example:terpenoids, is perceived by us largely through smell. People vary in their ability to smell these compounds - which affects how an individual perceives the taste of a given species of plant. From differening sensitivities to compounds, you get the 'I love cantaloupe, you hate cantaloupe' situation.

    In general people tend to eat the foods they were brought up with. So, if your family ate relatively few kinds of vegtables, then you might be inclined to think 'Most folks do no like vegetables'.

    And no, it is a simple question with a really complex answer.
  7. Dec 28, 2011 #6
    The above answer is spot on.

    I would add that historically, we evolved mostly worried about getting enough calories to survive.

    Fruits have sugar, which is fuel, and we are programmed to like the sweetness...which = calories.

    Lettuce is roughage, with little caloric value (Unless you add dressings with it, etc...)

    We are evolved to like fat. Fat is one of the best calorically nutritive finds in nature.

    So, if we had been pre-programmed to crave the grass instead of the mammoth, we'd most likely all be dead.

    If we'd been herbivores by nature, sure, then we'd crave the grass...and be designed to digest it, etc.

    We were designed to let other things eat the grass, and then eat them....and, if we could not find things that ate grass, we could root around for other stuff as a stop gap measure.

    Later, we developed the ability to cultivate crops, etc...but, again, preferentially grew the ones that tended to be higher in calories, oils, etc.

    Typically, if we grew grass, it was to graze the animals we intended to eat.


    So - That's why we have these built-in preferences, from an evolutionary stand point....add in what yo momma ate, and there's YOUR built-in preferences.
  8. Dec 28, 2011 #7
    I can't reconcile evolution with the bitter-taste gene for broccoli. I don't like broccoli because it's bitter to me and about 1/3 of all people.

    Why is this? It's healthy but bitter.
  9. Dec 28, 2011 #8


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    Perhaps it's due to diversity. Taste is a vitally important sense, it makes sense that having a diverse taste encourages species survival. Four out of ten organisms might like the taste of something, if they die the six that don't like it live on so that none of the next generation tries it.
  10. Dec 28, 2011 #9
    Fruits and veggies also have a vested interest in whether you want to eat them. If you reproduce/spread your progeny by counting on your seed being eaten, and then dispersed across the landscape along with a modicum of fertilizer, etc you want to be eaten. If being eaten is bad i.e. you lose the part of you that turns sunlight into energy, etc then you don't want to be eaten. So you can evolve poisons, that kill the things that eat you, or taste like poison to at least slow them down or develop chemicals to burn the mucous membranes, or spines to puncture them, and so forth; whatever makes less of you be eaten.

    So, broccoli doesn't reproduce by you eating the part you normally eat so it doesn't have a vested interest in tasting good. Frankly, it would rather you left it alone altogether.

    Some plants for example produce berries which are designed to be eaten (and then dropped off later wherever they are excreted) therefore fruit part of the berry is designed to taste good and be nutritious, so something will want to eat it. The seed itself is not digested, it passes through the digestive process unscathed, or even primed to be planted, etc. The seed itself might be poisoned though, in case anyone wants to screw with the plan, a cherry pit contains cyanide for example. Eat the cherries, but do not crush the pits and swallow them :biggrin:

    So, some fruits and veggies are designed to be eaten; the plant counts on it to reproduce/spread its seeds. Some are not designed to be eaten, and do what they can to foil attempts anyway they can. Typically, they they want you to eat the part they want you to disperse e.g. get the squirrel to eat the acorns, not the oak tree, etc.

    If they taste terrible, or are poisonous, but are nutritious enough, we might boil them or otherwise render them less deadly/objectionable. Some birds will eat clay to absorb toxins, so they can eat poisonous berries, and so forth. If the plant is poor at tasting poorly, and is simply bland, we can add dressings, or wrap some better food inside it and make a sandwich. And, as mentioned above if you like something your comrades don't, that's more for you and if a berry turns out to BE poisonous, well, only SOME of you drop dead.
    Last edited by a moderator: Dec 28, 2011
  11. Dec 28, 2011 #10
    tea jay you make it sound like intelligent design
  12. Dec 28, 2011 #11
    If broccoli can get credit for intelligent design, sure. :)

    I think its just a matter of what worked being kept, and what didn't work being eliminated over time. I think nature is more run by trial and error than by design. This way prototypes can continue to be present as long as they too can survive. IE: Why there are apes even if we evolved from them.

    If it were by design, the evolutionary solutions would have been more perfect. There were constraints on the biology. If your genes just could not mutate a certain way, you were stuck with tasting bad (vs being poisonous and reeking of impending doom to a potential consumer)....a helpful solution, but not perfect.
  13. Dec 28, 2011 #12


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    Let's not get bogged down into a discussion of ID, I don't see a problem with how Tea Jay phrased it. Terms like "supposed to", "designed" and "meant" are all perfectly fine if we use them within an evolutionary framework, the problem comes when people assume that those terms imply an intelligent agent which they usually do in other contexts.
  14. Dec 28, 2011 #13
    To be clear, I did not actually believe that broccoli designed the universe...or had even contemplated whether or not it wanted to be eaten. I was merely indicating that from an evolutionary stand point, it would rather you didn't eat it...rather than from a cognizant standpoint.

    I am not sure whether the eating of broccoli should be taught in schools, or left to the parents. ;)
  15. Dec 28, 2011 #14


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    Cruciate vegetables tend to be very good for you. I love steamed broccoli (even just plain) and I have to have cabbage in every boiled dinner I make. Still, I can't get cozy with cauliflower because it tastes too bland to me.

    I have a younger sister that refused to touch broccoli or cabbage. If the cabbage was used to make cabbage rolls (spiced ground beef, peppers, and onions in a nice tomato sauce), she would take some, and pretty much pick out the filling and leave the wrapping.

    Most attempts to get her to eat a proper mix of vegetables failed, even though my mother was an excellent cook. That was too bad, because my mother tried to base our summer-early fall meals around what was ripe in our vegetable garden, and having to feed "special" selections for a picky eater was not convenient nor cheap.
  16. Dec 28, 2011 #15


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  17. Dec 28, 2011 #16


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    Keep in mind that having such a large variety of vegetables and grains from so many places, plus selective breeding of modern varieties, and international travel and migration/immigration means our diets are quite different from our respective ancestors. Evolution and natural selection provide great answers to the question. If our ancestors were never exposed to a particular vegetable (or any other food) there was no selection to prefer the taste of it. There was selection to prefer the taste of the local vegetables. I'm not sure how much early exposure also contributes to taste preferences. Some things like tasting bitter in broccoli or spinach are genetic, but other preferences might have to do with what you were offered while young and learning the taste of foods or other acquired associations. For example, if you tasted something as a child and by coincidence got sick soon after, you can develop an aversion to that food even though it wasn't the cause of your illness. This is a protective mechanism to help you avoid poisonous foods, but can misfire if you just wound up with flu or got carsick after a particular meal.
  18. Dec 29, 2011 #17


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    I cannot find any references at the moment*, but it makes sense that leaves etc. are made poisonous or distasteful for the purpose of preventing them being eaten. That cooking is an invention that enabled our ancestors and ourselves to get round this to an extent. Some animals like elephants are known also to consume clays or chalks supposed to help detoxify what they consume. And we have also bred the nastiness out of many plants - I believe today's potatoes and tomatoes are substatinally different from the ones Columbus first came across.

    *The only article I remember was in the Science section of The Economist not many years ago
  19. Dec 29, 2011 #18


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    Not really; this is just part of many (possibly non-representative) observations that seem to support this claim; I have seen many people eating bananas, oranges, strawberries, etc. as a snack; I don't remember seeing anyone chomping on brocooli, cauliflower, tomato, as snacks. Salads are eaten more as meals than as snacks, in my experience.

    Thanks all for your inputs.
  20. Dec 30, 2011 #19


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    You've never seen someone eat veg or a salad as a snack? I've a few things to say about that; firstly many high street food shops in the UK at least now sell a variety of ready-to-eat salads as snacks, a trend that has been increasing for years now. Secondly what you see people eat is limited by where you are and what the cultural practices are. I'd be surprised to see someone eating bittergourd as a snack but then I'm not in a region of the world where that might be done.
  21. Dec 30, 2011 #20
    The answers were already presented as to why you might see fruits consumed w/o dressings, etc, and why lettuce, etc, would have dressings.

    In a nut shell, most humans evolved to crave caloric foods that would help them survive. Getting more iron or other micro-nutrient was a lower priority than getting enough calories.

    We therefore evolved to prefer sweet (High sugar/calorie) foods, and/or high fat/carbohydrate foods, as those were best from a survival standpoint.

    So a fruit is already sweet, and we would tend to eat it as is. Lettuce is dry and bland in comparison, broccoli is bitter to many people, and so forth, and to eat it, most people need to add a dressing, or cheese, etc...to find it palatable.

    Some people, in a conscious effort to eat healthy foods, or because they are too poor to afford dressings, do eat raw undressed veggies, etc as snacks. In a local supermarket for example, I can buy a bag of small green, yellow and red peppers, or broccoli, or celery, etc, designed for just that sort of snack.

    After that, its just personal preferences for taste. Just like some people put ketchup on eggs or steak sauce on steak or dip the pepper in ranch dressing...as it just tastes better than way to them.

    But the reason it does taste better to most people to add dressings, is to make the dry/bland/bitter veggie taste like something their nervous system accepts as good food.
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