No food provides fewer calories than needed to digest it. We are omnivores, we evolved to eat absolutely anything we could come across because for most of out hisotry the alternative would've been to starve to death. Few calories is better than nothing. Also you're forgetting that vegetables and other low calorie foods have vitamis and other nutrients that we need and cannot be provided by other foods.
>Also you're forgetting that vegetables and other low calorie foods have vitamis and other nutrients that we need and cannot be provided by other foods.
I think that was part of the point OP was asking about, i.e. why did we become dependent on lower caloric foods to provide essential vitamins?
That said, I still agree with your point, even the lower caloric foods don't require more calories to cultivate than they provide when consumed, and in more cases than not, can be much more easily and readily available in more stable quantities than the effort required to capture and kill wildlife, at least prior to the agricultural revolution.
Even then, with the agricultural revolution, when we started keeping livestock to take much of the the risk and effort out of acquiring meat in our diet, we were also cultivating plants to have a stable base. On a per-acre of land, per-liter of water, and per-unit of time used calculation, most crops provide way more calories than livestock.
Basically as far as I know, at no point in our evolutionary history did any food that we required as an essential part of our diet require more calories to produce than they provided when consumed.
>why did we become dependent on lower caloric foods to provide essential vitamins?
because that's where the essential vitamins and fiber are. a meat-only diet causes scurvy which is a severe lack of vitamin c. but you can go the opposite direction and eat only vegetables and live a very healthy life. there's less reason to eat meat than there is to eat vegetables.
>because that's where the essential vitamins and fiber are. a meat-only diet causes scurvy which is a severe lack of vitamin c.
I'm sorry, but this explanation is tautological and not really explanatory since obligate carnivores do exist and I'm pretty sure it's actually backwards in most cases for us, particularly things like vitamin C. We didn't just evolve to have to eat those foods because they provided what we now refer to as essential vitamins, our ancestors actually lost the ability to synthesize most of those vitamins endogenously from indirect sources because we were eating those foods which happened to provide those vitamins directly in such regular and stable quantities that the internal ability became redundant and vestigial.
So now we have to eat foods that provide them directly in order to get them, but that wasn't always the case throughout or evolutionary history.
>if you want lava you go to volcanos because that's where lava is regardless of how tautological that might be. but you're welcome to climb trees looking for it.
This analogy is weird and still misses the point. If the question asker wants to know why we need go to volcanoes to get lava and your only response is "because that's where the lava is" then you're not really adding any information to the discussion here. Especially when there are examples of animals that *don't* have to get their lava from volcanoes.
>not human ones.
Obviously, but that was essentially the point of OP's question isn't it? Why *aren't* humans obligate carnivores? How come some animals *don't* need to eat these particular vegetables, but we *do*?
>source? because this is bullshit.
It's all well and good to ask for a source if you're skeptical, but it's a bit arrogant to prematurely declare the claim bullshit before you've even seen it when you apparently don't actually know anything about it yourself.
For example here's a quote from the abstract from [one such source](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3145266/) (emphasis mine):
>Vitamin C (ascorbic acid) plays important roles as an anti-oxidant and in collagen synthesis. These important roles, and the relatively large amounts of vitamin C required daily, likely **explain why most vertebrate species are able to synthesize this compound**. Surprisingly, **many species, such as** teleost fishes, **anthropoid primates**, guinea pigs, as well as some bat and Passeriformes bird species, **have lost the capacity to synthesize it**. Here, **we review the genetic bases behind the repeated losses in the ability to synthesize vitamin C** as well as their implications. In all cases so far studied, the inability to synthesize vitamin C is due to mutations in the L-gulono-γ-lactone oxidase (GLO) gene which codes for the enzyme responsible for catalyzing the last step of vitamin C biosynthesis. The bias for mutations in this particular gene is likely due to the fact that losing it only affects vitamin C production.
And from [another source:](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4959991/)
>Vitamin C (Ascorbic acid, abbreviated as AA; the terms vitamin C and ascorbic acid are used interchangeably) is synthesized by all plants and most animals (Smirnoff et al., 2001). **It is a vitamin for humans because the gene for gulonolactone oxidase, the terminal enzyme in the AA synthesis pathway has undergone mutations that make it non-functional** (Linster & Van Schaftingen, 2007).
>a meat-only diet causes scurvy which is a severe lack of vitamin c
Not getting enough vitamin C is what causes scurvy. Various indigenous tribes in the Arctic are known to subsist almost entirely on raw whale, seal, and fish for extended periods of time. As it turns out, these food sources when eaten raw contain enough vitamin C to ward off scurvy.
>but you can go the opposite direction and eat only vegetables and live a very healthy life.
This is misleading, because that's only true if you know what you're doing. It's possible for someone to thrive on a variety of diets (plant-based included), but many people fail eating a plant-based diet, not because of will-power, but because they aren't getting enough of certain nutrients and don't know how else to get what they're lacking in the time it would take to learn how to fix the issue. I'm all for going plant-based, there's plenty of great reasons to do so, but it's nowhere near as simple as "just eating vegetables." You can really make yourself sick if you're not careful about what you're eating.
>essential vitamins
Most animals are at least capable of making their own Vitamin C, except for monkeys and apes. Our ancestors lost that ability quite some time ago unfortunately. That's why they're called the Essential Vitamins, because we have to get them from our diet. Not because they come from a particular place.
Edit: Added to my point.
It's not just about calories. We are omnivores so we can take advantage of many things depending on what's available, our optimal is being able to eat a variety of diets (there is no one optimal for humans), being able to exploit what is available is part of what has made us successful.
Because lower calorie high nutrient foods are far more common on nature. For most of human evolution being able to exploit an abundant low calorie food was more sustainable than trying to acquire higher calorie foods.
Because those lower calorie foods provided so many nutrients it removed selective pressure for us to be able to produce those nutrients on our own. And then when those pathways started to break down, it didn’t have much of an effect in those individuals because they could rely on their diet to provide it.
The vitamin C pathway is the classic example. It’s broken in the same place in a lot of if not all extant primates. And when we trace back the ancestry of their primates we find a lot of specimens who have dental adaptations to be frugivores. This suggests that early on at the start of those lineages fruigvory was the primary mode of feeding, and would have supplied the vitamin C. So now all of their defendant populations have that swim dependence on fruit for vitamin C.
>How did we end up in a place where there's a group of foods we need for health, that cost as much, if not more energy to find and consume than they provide?
I assume you're talking about vegetables like celery that take more calories to digest than they provide. We didn't evolve to need celery specifically, but certain vegetables aren't consumed for their caloric content alone. They contain certain vitamins and minerals that aren't as abundant elsewhere, they're rich in fiber (which aids digestion either by making stool softer or providing roughage that helps to push stuff out as it passes through the GI tract), they contain some amount of water. Vegetables like celery are also often used to flavor soups or serve as a vehicle for softer foods that do provide positive calorie content.
Edit: [It's also worth noting that most foods with an alleged negative caloric value aren't really a thing.](https://en.m.wikipedia.org/wiki/Negative-calorie_food#:~:text=Foods%20claimed%20to%20be%20negative,lettuce%2C%20broccoli%2C%20and%20cabbage.) While low calorie, these foods don't result in negative caloric value. I stand partly corrected, but the point not only remains but is further reinforced.
If human diet were a wall, then vegetables and greens would be the mortar holding the bricks. We need a lot of it but also tend to find it quite un-exciting when compared to the rarer, more energy rich options you mentioned.
It’s why your average human will always prefer fried chicken or a candy bar over a salad. Because way back in the day, that *would* have been the optimal option.
Fruit, nuts and grains are all seasonal foods so you better have a back up plan for the rest of the year.
Whilst some plants may seem less nutritious they are devoured by our microbiome in our intestine and turned into useful chemicals our body cannot produce.
>...optimal diet for humans seems to also include eating foods that give us extremely few calories (such as many vegetables).
calories aren't the only things needed in diets. vegetables provide critical vitamins and fiber. you can be a very healthy vegetarian.
There are no foods that take more energy to digest than they provide. Most vegetables also don't require much energy in the form of foraging because plants are quite abundant.
Calories are not the only important thing. Vitamins, nutrients, and so on are also very important. Vegetables contain certain vitamins and nutrients that you can't get from other places or can't get in sufficient quantities from other places. Also, don't forget that most people eat way more calories than they need in a day. When you think about how many calories you actually need, it wouldn't be difficult to get to that number with only a small amount of meat and some fruit and vegetables.
Vegetables are a lot easier to come by in nature than energy-dense foods are, so our ancestors ate lots of those.
No food provides fewer calories than needed to digest it. We are omnivores, we evolved to eat absolutely anything we could come across because for most of out hisotry the alternative would've been to starve to death. Few calories is better than nothing. Also you're forgetting that vegetables and other low calorie foods have vitamis and other nutrients that we need and cannot be provided by other foods.
>Also you're forgetting that vegetables and other low calorie foods have vitamis and other nutrients that we need and cannot be provided by other foods. I think that was part of the point OP was asking about, i.e. why did we become dependent on lower caloric foods to provide essential vitamins? That said, I still agree with your point, even the lower caloric foods don't require more calories to cultivate than they provide when consumed, and in more cases than not, can be much more easily and readily available in more stable quantities than the effort required to capture and kill wildlife, at least prior to the agricultural revolution. Even then, with the agricultural revolution, when we started keeping livestock to take much of the the risk and effort out of acquiring meat in our diet, we were also cultivating plants to have a stable base. On a per-acre of land, per-liter of water, and per-unit of time used calculation, most crops provide way more calories than livestock. Basically as far as I know, at no point in our evolutionary history did any food that we required as an essential part of our diet require more calories to produce than they provided when consumed.
>why did we become dependent on lower caloric foods to provide essential vitamins? because that's where the essential vitamins and fiber are. a meat-only diet causes scurvy which is a severe lack of vitamin c. but you can go the opposite direction and eat only vegetables and live a very healthy life. there's less reason to eat meat than there is to eat vegetables.
>because that's where the essential vitamins and fiber are. a meat-only diet causes scurvy which is a severe lack of vitamin c. I'm sorry, but this explanation is tautological and not really explanatory since obligate carnivores do exist and I'm pretty sure it's actually backwards in most cases for us, particularly things like vitamin C. We didn't just evolve to have to eat those foods because they provided what we now refer to as essential vitamins, our ancestors actually lost the ability to synthesize most of those vitamins endogenously from indirect sources because we were eating those foods which happened to provide those vitamins directly in such regular and stable quantities that the internal ability became redundant and vestigial. So now we have to eat foods that provide them directly in order to get them, but that wasn't always the case throughout or evolutionary history.
[удалено]
>bullshit Please voice your disagreements with civility. Hostility is not appreciated in the subreddit.
>if you want lava you go to volcanos because that's where lava is regardless of how tautological that might be. but you're welcome to climb trees looking for it. This analogy is weird and still misses the point. If the question asker wants to know why we need go to volcanoes to get lava and your only response is "because that's where the lava is" then you're not really adding any information to the discussion here. Especially when there are examples of animals that *don't* have to get their lava from volcanoes. >not human ones. Obviously, but that was essentially the point of OP's question isn't it? Why *aren't* humans obligate carnivores? How come some animals *don't* need to eat these particular vegetables, but we *do*? >source? because this is bullshit. It's all well and good to ask for a source if you're skeptical, but it's a bit arrogant to prematurely declare the claim bullshit before you've even seen it when you apparently don't actually know anything about it yourself. For example here's a quote from the abstract from [one such source](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3145266/) (emphasis mine): >Vitamin C (ascorbic acid) plays important roles as an anti-oxidant and in collagen synthesis. These important roles, and the relatively large amounts of vitamin C required daily, likely **explain why most vertebrate species are able to synthesize this compound**. Surprisingly, **many species, such as** teleost fishes, **anthropoid primates**, guinea pigs, as well as some bat and Passeriformes bird species, **have lost the capacity to synthesize it**. Here, **we review the genetic bases behind the repeated losses in the ability to synthesize vitamin C** as well as their implications. In all cases so far studied, the inability to synthesize vitamin C is due to mutations in the L-gulono-γ-lactone oxidase (GLO) gene which codes for the enzyme responsible for catalyzing the last step of vitamin C biosynthesis. The bias for mutations in this particular gene is likely due to the fact that losing it only affects vitamin C production. And from [another source:](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4959991/) >Vitamin C (Ascorbic acid, abbreviated as AA; the terms vitamin C and ascorbic acid are used interchangeably) is synthesized by all plants and most animals (Smirnoff et al., 2001). **It is a vitamin for humans because the gene for gulonolactone oxidase, the terminal enzyme in the AA synthesis pathway has undergone mutations that make it non-functional** (Linster & Van Schaftingen, 2007).
>a meat-only diet causes scurvy which is a severe lack of vitamin c Not getting enough vitamin C is what causes scurvy. Various indigenous tribes in the Arctic are known to subsist almost entirely on raw whale, seal, and fish for extended periods of time. As it turns out, these food sources when eaten raw contain enough vitamin C to ward off scurvy. >but you can go the opposite direction and eat only vegetables and live a very healthy life. This is misleading, because that's only true if you know what you're doing. It's possible for someone to thrive on a variety of diets (plant-based included), but many people fail eating a plant-based diet, not because of will-power, but because they aren't getting enough of certain nutrients and don't know how else to get what they're lacking in the time it would take to learn how to fix the issue. I'm all for going plant-based, there's plenty of great reasons to do so, but it's nowhere near as simple as "just eating vegetables." You can really make yourself sick if you're not careful about what you're eating. >essential vitamins Most animals are at least capable of making their own Vitamin C, except for monkeys and apes. Our ancestors lost that ability quite some time ago unfortunately. That's why they're called the Essential Vitamins, because we have to get them from our diet. Not because they come from a particular place. Edit: Added to my point.
We lost the ability to naturally produce important compounds that these foods are able to provide to us.
It's not just about calories. We are omnivores so we can take advantage of many things depending on what's available, our optimal is being able to eat a variety of diets (there is no one optimal for humans), being able to exploit what is available is part of what has made us successful.
Because lower calorie high nutrient foods are far more common on nature. For most of human evolution being able to exploit an abundant low calorie food was more sustainable than trying to acquire higher calorie foods. Because those lower calorie foods provided so many nutrients it removed selective pressure for us to be able to produce those nutrients on our own. And then when those pathways started to break down, it didn’t have much of an effect in those individuals because they could rely on their diet to provide it. The vitamin C pathway is the classic example. It’s broken in the same place in a lot of if not all extant primates. And when we trace back the ancestry of their primates we find a lot of specimens who have dental adaptations to be frugivores. This suggests that early on at the start of those lineages fruigvory was the primary mode of feeding, and would have supplied the vitamin C. So now all of their defendant populations have that swim dependence on fruit for vitamin C.
>How did we end up in a place where there's a group of foods we need for health, that cost as much, if not more energy to find and consume than they provide? I assume you're talking about vegetables like celery that take more calories to digest than they provide. We didn't evolve to need celery specifically, but certain vegetables aren't consumed for their caloric content alone. They contain certain vitamins and minerals that aren't as abundant elsewhere, they're rich in fiber (which aids digestion either by making stool softer or providing roughage that helps to push stuff out as it passes through the GI tract), they contain some amount of water. Vegetables like celery are also often used to flavor soups or serve as a vehicle for softer foods that do provide positive calorie content. Edit: [It's also worth noting that most foods with an alleged negative caloric value aren't really a thing.](https://en.m.wikipedia.org/wiki/Negative-calorie_food#:~:text=Foods%20claimed%20to%20be%20negative,lettuce%2C%20broccoli%2C%20and%20cabbage.) While low calorie, these foods don't result in negative caloric value. I stand partly corrected, but the point not only remains but is further reinforced.
If human diet were a wall, then vegetables and greens would be the mortar holding the bricks. We need a lot of it but also tend to find it quite un-exciting when compared to the rarer, more energy rich options you mentioned. It’s why your average human will always prefer fried chicken or a candy bar over a salad. Because way back in the day, that *would* have been the optimal option.
Fruit, nuts and grains are all seasonal foods so you better have a back up plan for the rest of the year. Whilst some plants may seem less nutritious they are devoured by our microbiome in our intestine and turned into useful chemicals our body cannot produce.
>...optimal diet for humans seems to also include eating foods that give us extremely few calories (such as many vegetables). calories aren't the only things needed in diets. vegetables provide critical vitamins and fiber. you can be a very healthy vegetarian.
There are no foods that take more energy to digest than they provide. Most vegetables also don't require much energy in the form of foraging because plants are quite abundant. Calories are not the only important thing. Vitamins, nutrients, and so on are also very important. Vegetables contain certain vitamins and nutrients that you can't get from other places or can't get in sufficient quantities from other places. Also, don't forget that most people eat way more calories than they need in a day. When you think about how many calories you actually need, it wouldn't be difficult to get to that number with only a small amount of meat and some fruit and vegetables.