Basically, everyone’s initial response is “we only have one stomach and can’t break down cellulose.” Which is true, but what if just simply cooked the grass.
The leafy parts of most plants have very little nutritional value when aten raw, but when you cook cabbage or lettuce for example, some of the cellulose breaks down and now the food is higher in carbohydrates. This is how it is for any vegetable; when you cook it long enough, heat chemically breaks down what we call “fiber” and makes it into a digestible carbohydrate. Notice how a strong onion becomes sweet after its been baked.
I don’t know the exact temperature or time of cooking it would take to break down grass, but maybe someone will figure that out.
Also, iirc all North American grasses are free of cyanide. Grass may not be the best food, but maybe cooked grass can be eaten as a survival food in tough situations. Humans around the world shouldn’t have starve when their is plentiful vegetation.
Well, we’re eating the seeds. If you let the grass in your lawn go to seed, I’m sure you could harvest and eat the seeds the same way you process wheat. Apart from the growing season, the yield would probably be low compared to more normal grass species used for edible grains.
Animals that eat grass (or leaves) exclusively have to be eating pretty much all of their waking hours to get enough energy to survive. Even if cooked, we would have to eat a heck of a lot of grass to extract enough energy to survive. As in, some number of pounds per day. And even then, the grass wouldn’t be a “complete protein” from a human point of view. And the cellulose would remain undigested. So basically, instead of dying fairly quickly from starvation, you would die more slowly from malnutrition while spending most of your time eating and pooping.
Now, if we hacked the human genome to give us the ability to produce all of the currently “essential” amino acids and other a few other things (such as Vitamin C) and gave us the ability to digest cellulose and lignin (not through gut bacteria but directly) then grass might be a more viable food. You’d still need a heck of a lot of it, though.
I’m talking about the actual green part of the grass, the blades and stem. People already eat leafy vegetables, and they do contain cellulose such as broccoli, brussels sprouts, cabbage, lettuce and celery. All of them are higher in calories after they baked/ boiled or etc.
Eating grass has been done in North Korea, South Sudan, and other places in times of famine. It’s a food of last resort: available, but barely edible, with little nutrition.
Cite for that? because everything I’ve seen says cooking does not alter the available caloric content of vegetables. it can soften the celluose structures, making it easier to eat; and in the case of tougher greens like collards can make the leaves release the micronutrients inside. But cooking isn’t going to convert cellulose into digestible carbs.
the best I could find:
“*Heat alone does not affect the calorie, fat, carbohydrate or protein content of vegetables. Because steaming doesn’t require the use of cooking oils or other additives, steamed vegetables are just as low-calorie, low-fat and high-fiber as their raw counterparts. The caveat is that they must be eaten plain to retain these nutrient values. *”
so, we don’t eat grass because there’s not a whole lot of nutrition available in it, it’s extremely calorie-poor (and no, cooking won’t change that,) and unlike ruminants and other herbivores we don’t have the symbiotic microorganisms in our digestive system to convert the indigestible parts of grasses to macronutrients we need.
eta: plus, if you watch cows for any length of time, you’d see another reason why. Cows basically do nothing but stand around constantly eating.
They may be higher in calories, but the cellulose still isn’t digested, and they still do not contain all the nutrients that humans need to live. Even eating a single type of grain (which has much more concentrated nutrients than the leaves and stems) leads to malnutrition and/or death. Eat only corn? You get this. Eat only rice? You get this. Vegetarians/vegans can survive at all only because they eat a mix of leafy vegetables, roots, and seeds.
Believe it or not, this topic was discussed on this board15 years ago.
About the same level of answers, as well.
Cooking the grass may make it soft, but it really doesn’t break the cellulose down at the molecular level. However, if you’re willing to add some cellulasic enzymes, give it two weeks to ferment, then distill it at a temperature of 79.5C,you can whip up some pretty powerful cellulosic ethanol, which you can then drink. Figure about 80 gallons yield for each ton of dried grass you start with.
Actually, we don’t really eat those for the calories. We eat them for bulk (satiety) and micronutrients (vitamins). Those vegetables do not have enough calories to sustain life in the amounts we typically cook them in. It’s the other things we add to them (oils, butter, bacon) that give them a lot of calories. Cooking may make more of the calories available for human digestion, but it can’t give them more calories than were there originally… and there’s not much to begin with.
That’s why most civilizations have staple foods based on some sort of seed (rice, wheat, corn)… it’s the grain (seed/fruit) part of plants that have the most caloric content, not the leaves. That’s also why birds go after those.
Even as a vegan, most of our calories come from grains and fats, not leafy greens. The greens are there for the micronutrients, and if we’re honest to ourselves, because they’ve been marketed as healthy and our culture has assimilated that thought. You could survive off soy/quinoa/hemp/corn and beans and multivitamins if you preferred.
No.
Look up the process for determining the acid or neutral detergent fibre content of plant matter (i.e. the hemicellulose, cellulose, and lignin fractions) and what remains is not digestible carbohydrate.
You can heat wood as long as you like but will never get anything which is digestible by a monogastric mammal.
Its actually not too terrible, depending on what its cooked with, a little wild onion will do.
Not all grasses are the same of course some are soft some not so much.
You’d stay alive long enough to work out some other means of food sourcing, but yea you wont enjoy it too much.
You aren’t kissing about animals having to eat nonstop. Our horses and donkey rarely do anything else. Well, that and poop, so much poop, you have no idea. But it always amazes me that they eat 18 hours a day it seems. If I awake at 3am I go look outside, they’re still eating.
We haven’t had a lot of rain in the past few months so the grass hasn’t been sufficient for them. We’ve supplemented with hay. We get the big rolls of hay that must weight 600 to a thousand pounds. Our two horses and two mini donkeys will polish off that roll in about a week. It’s mind boggling how much they need to consume.
Cooking may not make the fiber available, but in some vegetables it breaks down the cell walls and makes some nutrients inside the cells available. I believe that raw potatoes have almost no caloric value and the same is true, to a lesser extent, of carrots. But I don’t think cooking affects leaves in the same way.
I recall reading somewhere that horses, unlike cows, are not ruminants. They don’t recycle cud and let bacteria do a lot of the digestive work on the cellulose. As a result, they need a lot more grass, they rely much more on the accompanying seeds etc., and their undigested cellulose comes out as fibrous meadow muffins instead of liquid bacteria-fermented byproducts.
Cooking does not break down cellulose into digestible starch. That’s completely false.
Yes, you could cook grass into a pulp and eat it. And it would give you some vitamins and whatever, and a tiny amount of calories. And when people are starving, they will try this.
But you can’t get enough calories from grass to sustain human life. It’s just physically impossible. You can’t digest cellulose, and you can’t break it down by cooking.
Yes, there animals that eat grass. But even they can’t break down the cellulose in grass. Instead bacteria that live in their digestive tract break down some of the cellulose, and that get’s digested.
But even with that method, as has been mentioned, you would need to eat a crazy amount of grass to stay alive. Even if we had symbiotic bacteria to break down cellulose into digestible sugars, our digestive system isn’t capable of handling the throughput needed. Nor the teeth needed to chew that shit into a pulp.
To create a human that could survive on grass you’d have to completely re-design our digestive system from tooth to tail. And those people would spend most of their days out in the fields eating constantly to avoid starvation.
This is one thing it’s hard for people to understand about herbivores. You look outside your window and see all the plants, and figure it’s pretty easy to just eat some leaves and call it a day. But most plant parts are very low in nutrition, and many contain substances to make them difficult to eat. Herbivores have to be highly selective to only eat the plants and plant parts that they can digest. So when herbivores starve to death, it’s almost always with a full stomach. They can starve to death despite eating constantly if they can’t find enough plants or plant parts of high enough quality to keep them going.
And of course, keeping this biochemical digestion process on track is a tricky prospect. Herbivores can literally up and die if you change their diet radically.
Yes, of course we could use some sort of industrial biochemistry to produce human-edible products out of forage grass.
But would that be cheaper than growing wheat and only keeping the seeds for human consumption and feeding the rest to livestock?
The question was, why can’t people just go out, cut a bunch of grass, and cook it up on the stove into a nutritious stew.
And the answer is that the grass pulp you just cooked will contain almost no human-digestible calories, because most of the grass is composed of cellulose which is not broken down by cooking.
And the same thing is true for lots of other vegetables, which are not significant sources of calories. You can eat lettuce and celery all day and you’ll die of starvation with a full stomach.