Why can't humans survive on grasses?

in #stemng6 years ago
Few years ago (2014 to be precise), I read with interest the story of a South African pastor that told his congregation to eat grass, claiming that doing such will draw them closer to God. Trust the gullible, miracle seeking Homo sapiens ; a lot of the congregation obliged the supposed man of God and the outcome was nothing short of a disaster. The action was greeted by a cacophony of groans caused by stomach pains and vomits. Funny enough, a few of the human-turned ruminants actually claimed various degrees of healings as a result of feeding on the grass. Different strokes for different folks. Perhaps my friend, @zest would have a better version of the story to tell us.


There is no iota of doubts that the earth is blessed with a variety of plants and animals that serve as sources of food for human consumption. The ancestors of man started out with eating raw leaves and fruits in the jungle before the discovery of fire and crude weapons which enabled them to cook their foods and hunt for games for the purpose of meat respectively. One of the arguments of vegetarians is that humans are best adapted to eating plants simply because our ancestors fed on strict plant diets. If such is the case, then we do not also need to cook our meals, we can as well just be feeding on grasses and other plants like ruminant animals.

Even though records have it that our ancestors observed plant diets, I am sure grasses were not one of their foods. The plant cell is made up of easily digestible cell contents and somewhat indigestible cell wall made up largely of cellulose and lignin. The cellulose, pectin, gums, mucilage and lignin component make up what is referred to as fibre and in order for digestion to successfully be completed in the human alimentary canal, a certain amount of fibre, known as dietary fibre is needed. While pectin, gum and mucilage portion of the fibre can be broken down during digestion and referred to as soluble fibre, cellulose and lignin are totally undigestable and are otherwise known as insoluble fibre. Soluble fibres function by lowering low-density lipoproteins cholesterol level in the body while the insoluble fibres act by adding bulk to faeces and in doing such, prevents constipation and its associated problems.


Having highlighted the benefits of soluble and insoluble fibre, one begins to wonder why then do grasses constitute problems for humans when it comes to digestion. The answer is not far-fetched. Grasses generally have higher insoluble fibre in form of cellulose and lignin and will be passed out in faeces as consumed, with little or no modification in most cases. The presence of too much insoluble fibre in the diet of humans would lead to different kind of problems ranging from stomach pains to nausea. The amount of insoluble fibre in grasses generally doubles the amount in other plant families.


Animals that feed on grasses have a digestive system that is well suited to digesting what would otherwise be an insoluble/indigestible fibre in the human digestive system. These animals are generally referred to as ruminant animals. Instead of a single monogastric stomach that is the characteristic of humans, ruminants have four-chambered stomach lined with microflora of bacteria, protozoans and fungi that help in the digestion of cellulose as well as synthesize essential vitamins for the proper nourishment of the animals. The first stomach chamber which is known as rumen acts as a fermentation chamber for consumed grasses. There, the grasses are mixed with saliva and fermented through the actions of symbiotic microorganisms that produce cellulase enzyme which is necessary for the digestion of cellulose.


The end products of fermentation are carboxylic acids in form of ethanoic, propanoic and butanoic acids as well as carbon dioxide and methane. The acids are utilized as a source of energy during ruminant's respiration. The chemical reactions that accompany the fermentation process generate the energy needed for the metabolic processes of the microbes and creates an ideal environment for them to thrive.


The partially digested grasses which are commonly referred to as cud then move from the rumen to the second stomach chamber, the reticulum, where is formed into pellets. The pellets are regurgitated back into the mouth where it is properly rechewed, a process known as chewing the cud or rumination. The food is thereafter re-swallowed into the third stomach chamber, the omasun where it undergoes further fermentation before moving into the abomasun. The abomasun represent the 4th chamber and functions like the stomach found in humans. From there, the food undergoes the normal digestion process associated with mammalian digestion.


Without the complex digestion procedure associated with the ruminant's digestive system, survival on grass-based diets would have been close to impossible. Generally, grasses have low digestibility due to the presence of lignin which makes up the midrib of their leaves and as such, ruminant animals and their likes have to consume a rather larger quantity of grasses in other meet their body's energy requirement. This generally leads to high faeces turnouts which could be harmful to the environment in the long run.


Therefore, next time your pastor asks you to eat grasses with the aim that it will get you closer to God, you know what's up. Even if such were to be true, it means ruminants are closer to God than humans. Are they?



Thank you all for reading.


References


wikivet

the cattle site

waikato


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Hello @gentleshaid

Therefore, next time your pastor asks you to eat grasses with the aim that it will get you closer to God, you know what's up. Even if such were to be true, it means ruminants are closer to God than humans. Are they?

You can imagine how gullible some people can be. Even those who obeyed the said man of God and claimed Nourishing outcome should have continued and let's see what happens in the long run.

I like how you made everything simple here using a combination of dietician and Agriculturist approach to highlight the biochemical processes involved in digestion and how they differ with those of herbivores.

Anyone who has ears should hear.

Regards.

@eurogee of @euronation and @steemstem communities

Hehe. He who has ears, let him hear what the spirit is saying.

Thanks @eurogee.

Maybe vegetarians should also be aware of this truth. :)
Nice piece buddy

True facts. Currently, man can't adapt to eating raw plants, because we don't have the digestive system of a ruminant.

Meanwhile, I feel that our ancestors though; precisely, the early men may have practised this until evolution occurred, because there was no such thing as cooking, then.

If we study humans biologically, and compare it to our intellect, It may show that man currently isn't completely a higher animal. Our biology is weak, whereas our intellect is high, the equation is balanced. This is vice versa for many animals.

We must cook to eat, and other limitations such as using vehicles to travel long distances, etc.

Man can't currently survive many things other animals face.

I am SyNick

If we compare ourselves to some animals, I totally agree with you. The first thing in the affairs of man is survival. Man will eat anything as a last option to survive. Many might not survive it while might. Those few will reproduce to give offsprings that would be better adapted to eat what their parents ate/are eating. It is called natural selection.

Yes, that's true, I suppose, that's what we have been experiencing in the newer generation.

If you are starving to death it would seem stupid to eat grass since you would waste energy in its digestion. THe smarter thing to do is to search for the earth worms and other insects guarteed to be right beneath the soil. Where there is grass there is worms.

Grass-eating-church 😁😁...lemme tag the members to come read
@grasseatingch @grasschmembers

Lol...you can't be serious. How I wish we had some members of that church on here.

I’m glad I only have one stomach. Carnivores/omnivores have all the fun. Actually, I wish I was like a lion so I could just go to the all-you-can-eat restaurant once every two days.

Lions feed like once in three days. easy life. Wouldnt mind being one too :)

Thanks to God that we dont only rely on vegetables. Our digestive system is built well enough to consume meats and thats what I love the most. :D
A good article shaid bro, cheers!

Thanks @ied. I also love meats :)

What a rib cracking entry😅. Nice one buddy, I want to ask, since digestion of insoluble fibre by ruminants takes place in four chambers and also involves chewing of cuds, does that mean that when those animals eat soluble fiber like normal cooked foods for humans, the food won't take the route of four stomachs?

Ruminant have the enzyme cellulase too which makes it easier for them to break down grasses. Also it cellulose is a polysaccharide and involves enzymes to be broken down just like starch too. Humans do not have cellulase making digestion of grasses and plant limited. Well said sir. Thanks @gentleshaid

You are absolutely right. Thanks for the short but terse addition.

I think I saw a video somewhere saying that, we as a human as evolved from our ancestors in terms of what we can eat and what we could not because of the relationship between the brain and stomach. Our ancestors have a big stomach and small brain while we were the opposite. We can't have both because the energy needed for running both would be enormous. That's why we can no longer process fibre which can be found abundantly in grasses.

I'm not sure how accurate is this information, but I'm sure felt that was interesting.

Unless there is an evidence pointing to the fact that our ancestors had multiple chambered stomach and chew cud like ruminants, a large stomach does not confer any adaptive advantage to digest fibre in any form. In essence, I do not think our ancestors were able to digest grasses. They could have been plant eaters but grasses were not part of their diets

Before i say anything else, let it be known that there is nothing anybody is telling me to make me eat grass (I know people like @addempsea and @real2josh will soon come and offer me money).

That said, this is a very creative way to explain the four compartments of the ruminant stomach, and the role they play in the digestion of grasses. I've learnt my lessons, more from the structure of this article. Bravo

Perhaps if they offer you enough SBD/steem, you might consider it. Afterall, we all have our prices.

Thanks for coming around.

Please let me see how much they can offer first, then we shall have the discussion again...

Are u sure about @sogless. Let me tell you something

Tell me what?

@sogless there's always a right price for everything

How much STEEM are you offering bros?