Learned Something Interesting Today in School About Nutrition and Foods...

[Jessika]

We do have a class on nutrition, and today we talked about proteins and how the body used them/broke them down, etc. I learned that after the animal ingests protein, it is then broken down into amino acids and the amino acids are then reconfigured to create NEW proteins needed by the animal. We talked specifically about dogs.

Then I learned something that nearly blew my mind.

Too much protein is bad because it causes your kidneys and livers to work harder.

And the kicker... that there is no difference between plant and animal protein because once the body breaks it down into amino acids it can not tell the difference between "plant" and "animal" proteins.

Imagine the alphabet. The alphabet is made up of letters (amino acids). Depending on how you arrange the letters (amino acids) you get different words (proteins). So the word (protein) "ate" includes the letters (amino acids) "a", "t" and "e". You can take those same letters (amino acids) and create a different word (protein), "eat".

Say "ate" is an animal protein, and "eat" is a plant protein. It doesn't matter which type of protein you are receiving because once they are broken down, they both consist of the same letters, or amino acids.

Therefore... corn isn't necessarily a "bad" ingredient. Neither is grain. They are just cheaper and still contain the essential amino acids, even though the proteins carrying them may be different.

So long as the animal is receiving proteins that contain the necessary amino acids they need, it does not matter what source they are coming from.

And we were also taught that even wolves in the wild weren't 100% carnivores. They are omnivores and included things like grass and bark in their diets.

This completely goes against everything I taught myself about nutrition. :(

Plus having too many high-protein sources in your foods can make your liver and kidneys work harder getting rid of the excess, which can lead to problems with them later on down the road.

Now I'm wondering if my food really *is* as good as I'd thought it to be originally as when compared to other "grocery store" brands.

Sorry if this was hard to understand... I'm still learning myself. Any thoughts to this or has anyone else took a canine nutrition course so we can "compare notes"?

[Giselle]

I took college level bio and will hopefully be majoring in bio soon (fingers crossed that Cal likes me :p), so it's been a while since I've done anything remotely close to protein synthesis. However, from a few nonchalant courses in health, plants are sources of incomplete proteins. IIRC, only animal products contain complete proteins.

So, sure, theoretically, a dog can live off a vegetarian diet. However, it does take a lot of tweaking and balancing. Also, iirc, high levels of protein only affect the kidneys and livers of dogs whose organs are already compromised. Healthy dogs should be able to tolerate levels of high protein well.

Studying bio really breaks life down into bits and pieces that make you reconsider everything you've learned and believed in. After awhile, I learned to just trust Nature and my own instinct =)

[bckrazy]

I whole-heartedly agree that too much protein is a bad thing... the important question is how much is too much, and how much is too little? Some might argue that a raw diet is all protein - it isn't. Much of it is moisture, fat, bone, etc.

However, I disagree, that there is no difference between plant protein and animal protein, to an opportunistic carnivore (NOT an omnivore).

When starches are broken down, they must first be broken into sugars in order to be usable. Dogs and cats do not normally produce enzymes in their saliva to actually break-down carbohydrates and starches. Amylase in saliva is something omnivorous and herbivorous animals possess, but not carnivorous animals. Their pancreas is forced to produce large amounts of this enzyme to deal with the starches. Dogs also do not have the kinds of good bacteria that break down cellulose and starch for them.

Ideally, a dog can only digest about 50% of a grain-based food. That is why manufacturers of these food have to add a plethora of extra vitamins and minerals, to compensate. So the question then becomes... would you rather your dogs get their necessary nutrients from additives, vitamins, and only partially digestible matter; or from a natural, biologically appropriate source?

Don't write off everything you've learned about nutrition, from one single lecture... take it with a grain of salt, and continue researching independently (reliable sources, of course). That's what I think, anyway. : )

[dragondawg]

And the kicker... that there is no difference between plant and animal protein because once the body breaks it down into amino acids it can not tell the difference between "plant" and "animal" proteins.

Absolutely true. The only difference between animal and plant protein is the composition of the protein, and the digestability of the protein. Consider the difference between feeding a ribeye steak vs cooked whole kernel corn meal to a dog. Most likely the steak will have all "essential" amino acids contained in the protein. Where an "essential" amino acid is one that can be altered by the host body to produce other amino acids lacking in the diet. The proteins are readily available to the enzymes to break down into the amino acids. With corn the starch-cellulose or cell wall has to be broken down first, before the proteins can be accessed inside the corn cell and cleaved. The second difference is that corn lacks lysine and tryptophan which are "essential" amino acids. Although if not already available there are strains of corn being genetically engineered that will produce lysine. The lack of lysine has always been a problem for 3rd world human populations that rely on corn.

Thus the difference between pure meat protein and corn to a dog's biochemistry in regards to its protein or amino acid needs: Longer digestability required for corn, and a strick corn diet may lack lysine and tryptophan. But as you were taught a leucine amino acid molecule from corn is identical to a leucine amino acid from meat.

The commercial dog foods get around the all corn diet problem by doing the obvious - the dog food is not all corn. The degree that it does not contain grains basically determines the amount of total protein/fat vs carbohydrate in the diet. For the dog with kidney problems its dog food will have more grains since the total protein content is lower, while the carbohydrate content is higher. But again although a larger part of the low protein dog food will have corn and other grains in it, there will still be enough meat sources added to provide all of the "essential" amino acids.

Be prepared to be lectured about the wonders of a barf diet as being natural, or how a wolf is a meat eater blah blah blah. It's like religion. But as you have learned and will hopefully explore more education on your own, the perception of human taste buds does not reflect the reality of canine nutrition.

[Jessika]

I will have to ask about whether plants are sources of incomplete proteins, as if they are then we haven't touched base on that yet.

Remember like I said this is all based loosely off of one lecture. :) We did learn about carbohydrates and fats today, too, but I'll save that for a rainy day haha

[bckrazy]

Be prepared to be lectured about the wonders of a barf diet as being natural, or how a wolf is a meat eater blah blah blah. It's like religion.

I don't think anyone is going to lecture Jessika. I know she is pretty informed, as far as nutrition, and a lecture is not necessary.

I don't appreciate the religion comment. I do follow a religion... but it has nothing to do with raw meat and/or bones. Sue me for trying to feed my dogs what is best for them. D:<

[Catlady711]

I do follow a religion... but it has nothing to do with raw meat and/or bones.

Ok, slightly off topic here but...

For me personally I don't follow a 'religion', I just follow Jesus Christ.

[cali]

yes dogs are omnivores, this is why I feed plant matter as well as meat to my dogs :p

as for corn not being bad? no so. corn is not considered bad because it isnt meat, its considered bad because it isnt digestable. it really doesnt matter where the proteins come from if they cant break it down in the first place. this is where the problem lies in many grocery store brands, they include the protien from the high levels of corn in their break down, but the dogs cant actually GET any of the protein from the corn, making it a completly usless filler, and considerably dropping the actual levels of protein in the food.

as for protein amount? it depends on the dog, you dont want to always go low protein, you need to take into account the activity level, size, structure etc.. as all of these can have an effect.

[bckrazy]

For me personally I don't follow a 'religion', I just follow Jesus Christ.

Umm, ok... beyond off topic.

Have Jesus Christ's teachings not been made into a religion? Called Christianty?... What is the difference between following Christianity and following Jesus Christ? They SHOULD be one in the same. It's bad people that manipulate a religion into something it isn't for their own benefit; I don't blindly follow people - but I do follow a religion, meaning, the teachings and beliefs of it.

This isn't a religious debate, and I don't see the point of your post anyway. You can take it into General if you'd like.

[Jessika]

On the topic of corn not being digestible-- can you refer me to any scientific documents that discuss this? I'm not trying to "prove anyone wrong", I'm just honestly trying to learn past "well, corn is bad just because". I want to know the scientific breakdown as to why it's bad, you know?

Thanks guys. I'll be sure to talk to my instructor about these things after class Monday if we have time :)

[dragondawg]

I don't think anyone is going to lecture Jessika. I know she is pretty informed, as far as nutrition, and a lecture is not necessary.

I don't appreciate the religion comment. I do follow a religion... but it has nothing to do with raw meat and/or bones. Sue me for trying to feed my dogs what is best for them. D:<

Every last one of these food threads have turned into threads of religious zeal, where scientific facts are subordinate to half baked beliefs. An example above per your contention:


Dogs and cats do not normally produce enzymes in their saliva to actually break-down carbohydrates and starches. Amylase in saliva is something omnivorous and herbivorous animals possess, but not carnivorous animals.

First of all amylase is produced by the pancreas and dumped into the bile. It is continuously present in dogs regardless of the diet, and is measurable in the serum at any given time. You also need to educate yourself as to the relationship between stored fat, starch, and carbohydrates. Rather than rely on some blog site "religion" that doesn't understand the basics of biochemistry.

And if you don't like the word "religion" too damn bad.