Hi

Our bodies recycle approximately 80% of our protein; cooked protein is denatured and largely unusable, thus our protein need is far lower than what is taught by conventional dietetics. A small avocado will provide more usable protein then a huge steak because cooked protein in meat is deranged and mostly unavailable to our liver, the organ which makes all of our body’s protein.

is this true??:confused:
am i wasting the protein in food by cooking steaks chicken breasts?


http://www.living-foods.com/articles/avocadoarticle.html

i'm allergic to avocados :(

and wasting or not, i'm not about to eat raw chicken :)

There's a thread around here somewhere if I could find it...

It discusses how cooking your meat and eggs breaks down some of the larger proteins making tham MORE bioavailable than if they were raw.

Edit: Here's (http://forums.johnstonefitness.com/showthread.php?t=35439&highlight=raw+egg) one thread of the many on the topic.

Hi

Our bodies recycle approximately 80% of our protein; cooked protein is denatured and largely unusable, thus our protein need is far lower than what is taught by conventional dietetics. A small avocado will provide more usable protein then a huge steak because cooked protein in meat is deranged and mostly unavailable to our liver, the organ which makes all of our body’s protein.

is this true??:confused:
am i wasting the protein in food by cooking steaks chicken breasts?


http://www.living-foods.com/articles/avocadoarticle.html

If we didn't denature protein, we couldn't use it! What do you think happens in digestion? You have to uncoil the structure to release the amino acids.

Read up on pepsin and peptides.

If you burn protein it's unusable. Cook your food, otherwise, usable/unusable protein will be the least of your worries.

Unless you kill it, clean it and eat it that day....raw meat diets aren't advisable.

cooked protein is denatured and largely unusable

No.

When you eat food, it goes in the stomach. Just about the first thing that happens in the stomach is the food is doused with mostly hydrochloric acid (http://en.wikipedia.org/wiki/Gastric_acid). The point of that is that this acid mostly kills anything that might be living in there. It kills it largely by denaturing all the proteins that it can, and this exposes the main chain of the denatured proteins to pepsinogen, which tears the chains apart into short chunks.

Cooking actually aids digestion, especially with protein. If you feed two people the same amount of protein Calories, but one of them gets cooked and the other raw, then the person eating the cooked protein doesn't have to spend as much energy digesting the protein. So cooking is thought to have been a big advantage to early humans. (http://www.news.harvard.edu/gazette/2002/06.13/01-cooking.html)

Now proteins that are in food are (hopefully) from other species; and they are also in the digestive tract, as opposed to magically transported into other tissues. Our functioning proteins are supposed to be expressed in certain places and under the control of various mechanisms. So we do not just incorporate food proteins as we find them into our bodies. We tear them apart into the raw materials for proteins and then rebuild them according to our own DNA (unless a virus is hijacking our protein synthesis resources).

So yes, cooking denatures proteins. And that's a good thing.

If you want to worry about bad effects of cooking, I think you want to consider what happens to vitamins. Cooking is not only good for vitamins.

If you want to worry about bad effects of cooking, I think you want to consider what happens to vitamins. Cooking is not only good for vitamins.


And fats. Overheating of oils, especially vegetable oils can be very bad.

So yes, cooking denatures proteins. And that's a good thing.

If you want to worry about bad effects of cooking, I think you want to consider what happens to vitamins. Cooking is not only good for vitamins.

<Moderator/s: suggest moving this thread to "Nutrition & Supplements>

Zen, et al:

Help me to understand something:

Is the "cooked vs. raw" a yes or no proposition with regards to digestible/available protein in animal meat? Meaning is it one way or the other?

Reason for asking: questions regarding typically consumed animal protein-

* Medium-rare vs. well-done (but not burned) steak: which level of cooking makes more protein available for the human?

* Similar to above: cooked fish vs. sushi?

* Raw vs. pasteurized dairy? (or even cold vs. boiled milk)


~B

Zen, et al:

Help me to understand something:

Is the "cooked vs. raw" a yes or no proposition with regards to digestible/available protein in animal meat? Meaning is it one way or the other?

Reason for asking: questions regarding typically consumed animal protein-

* Medium-rare vs. well-done (but not burned) steak: which level of cooking makes more protein available for the human?

* Similar to above: cooked fish vs. sushi?

* Raw vs. pasteurized dairy? (or even cold vs. boiled milk)


~B


OK it's never all or nothing. Denaturation is good, but once the protein chains are pretty much uncoiled, further cooking will make little difference. Doesn't really matter between fish or steak.

Raw vs. pasteurized milk is a slightly different issue. The protein gets just denatured enough to kill a lot (but not necessarily all) of the pathogens that might be in the milk. There is some denaturation of protein, but not as much as if you really cooked the milk. The milk will curdle instantly when it hits your stomach though; since it's a liquid you don't have to chew it, etc., like a steak. So the denaturation of milk by pasteurization doesn't really help the availability of nutrients that much, it's pretty much a food safety issue.

Now there are a lot of things in food other than just proteins. There are various hormones and vitamins. They all have different stability when cooked, and your body has different goals in processing them. For example any kind of DNA or RNA in the food? You pretty much want that stuff scragged beyond recognition. Fat? from a Calorie point of view your body wants to use it basically as is. Hormones and hormone mimics? Kill kill kill. Vitamins? Treat them with kid gloves. Food chemistry and biology is complicated.

And fats. Overheating of oils, especially vegetable oils can be very bad.

Yeah that one is complicated. Oxidation of fats is always bad. Heating of fats is not as clear; saturated fats are not that bothered by heating (mmmm gravy). Like you say, vegetable oils (which can be pretty unsaturated) don't do well with heat.

Vitamins? Treat them with kid gloves. Food chemistry and biology is complicated.

Have you seen the studies about microwaving vegetables destroying most of the vitamin/antioxidants? On the other hand, steaming does little to damage them.

However, I've also seen stuff showing things nearly opposite. Don't know what to believe.

Have you seen the studies about microwaving vegetables destroying most of the vitamin/antioxidants? On the other hand, steaming does little to damage them.

However, I've also seen stuff showing things nearly opposite. Don't know what to believe.

Vitamins are tough if you want to get them all from food. Real easy to fix that with a multivitamin supplement though. Sometimes the easy way is the best way.l