juniper wrote in another thread:

When we are born, we have an abundance of these enzymes, but unfortunately we use them due to eating cooked food. When one eats "raw" they dont have to pull from the enzymes in their body as the enzymes are already in their food, thus they don't deplete their supply. This is also why raw food is easier on the body then cooked, it has the digestive enzymes that break the food down properly, where cooked food does not. Disease starts to happen when the body is depleted of these enzymes.

I'm not looking to start a fight and generally I am very sympathetic towards new theories and ideas.

However, I do find it imortant to point out here, that this Enzyme theory has no scientific basis. I.e., it has never been shown that any "living" (or perhaps intact would be a better word) enzymes that we consume are actually able to survive in the stomach's acid environment and do anything for us. Also, the theory that the body has a limited supply of enzymes and that this supply can be depleted by cooked foods has not been proven.

Personally I prefer the scientific explanation for why raw foods are very healthy. It's not because of their enzymes, but because they have the most nutrients, vitamins, minerals, fibers, etc per calorie, and because they (especially fruit) are easier to digest for our digestive systems. Since cooking always destroys nutrients, it's best to consume the foods in their raw form.

Considering our evolution, it's no wonder that we developed digestive systems that are best suited to process fruit and vegetables. And by not cooking them, we maximize their nutrient content, preserving most of them.

So, IMO the main message is: eat more fruit and vegetables, and the corollary is that we should eat them as unprocessed as possible :)

"they (especially fruit) are easier to digest for our digestive systems. Since cooking always destroys nutrients, "

Actually, foods that are commonly cooked are made easier to digest by cooking. Eat a raw potato and tell me if I'm wrong. Same with succulent beans. And many other foods. Fruits are generally no easier to digest when cooked.

While many nutrients are killed off by cooking, other that remain are made easier to digest. Others still, are made possible to digest, while before hand they were there, but not able to be digested.

Cooking can be viewed as partial pre-digestion.

Carrots have more calories when cooked. More of the carbohydrates are made digestible. This is a case of cooking providing nutrients (carbohydrates) for us, not destroying them. On the other hand, undoubtedly some micronutrients are destroyed, or reduced in quantity, by being cooked. Vitamin C is definitly reduced in quantity by beeing cooked. But what is more important, vit c or carbs? I would say carbs. Tho both are necessary, the need for carbs is more urgent. Can't do anything without energy to operate on -- vit C can wait awhile.

However, I do find it imortant to point out here, that this Enzyme theory has no scientific basis. I.e., it has never been shown that any "living" (or perhaps intact would be a better word) enzymes that we consume are actually able to survive in the stomach's acid environment and do anything for us. Also, the theory that the body has a limited supply of enzymes and that this supply can be depleted by cooked foods has not been proven.

Yep, pseudoscience at its best (or worst). Most plants do their darndest to avoid being eaten and digested. Also enzymes have a very specific range of conditions at which they are active. I can see a lot of raw food is better for us, but not because of some badly understood bit about enzymes.

Considering our evolution, it's no wonder that we developed digestive systems that are best suited to process fruit and vegetables. And by not cooking them, we maximize their nutrient content, preserving most of them.

So, IMO the main message is: eat more fruit and vegetables, and the corollary is that we should eat them as unprocessed as possible :)

Well, here is a bit of a bad argument right there. A lot of people assume that human evolution stopped about a million years ago. Basically, there are significant tradeoffs in regards to cooking vs. raw. On the one hand, cooking food does destroy some nutrients but makes other nutrients easier to extract and digest (such as carbohydrates). It is not always the case that nutrient content is maximized by lack of processing.

From personal experience, I'm pretty sure that cooking veggies makes them a heck of a lot easier to digest. When my stomach is acting up, I can't even think about eating raw veggies! But steamed are usually okay. And also I'm wondering about broccoli for example, I've read from reputable scientific sources (can't remember where right now- but multiple times) that the body can't absorb the calcium in broccoli UNLESS it's cooked.

I recently found this article: Why Eat More Raw Foods?(eatveg.com) (http://www.eatveg.com/WhyRaw.htm) and I immediately thought it was pulling my leg. I started this thread (http://boards.straightdope.com/sdmb/showthread.php?s=&threadid=212280&highlight=enzymes) on another board if anyone is interested. Here is a quote:

Some other reasons why the "cooking food destroys enzymes and is therefore bad" theory is wrong:

1. The enzymes in food aren't human enzymes, so they're useless to humans. It's far more efficient to break them down and make new, human enzymes out of the raw materials.
2. Not only are they useless, some of the alien enzymes may actually be dangerous. They may be pathogenic (e.g. some viruses), or they may interfere with human enzymes.
3. The human body has a complex mechanism for maintaining the appropriate levels of all enzymes. Enzymes are constantly being produced and destroyed; the balance is maintained very well unless there's a genetic disease present.
4. Very few Americans or people from other cultures where large amounts of meat are eaten would be deficient in the raw materials for making their own enzymes. A balanced vegetarian diet is also sufficient.
5. Cooking food doesn't destroy enzymes (unless you burn it). It denatures them -- causes them to change their shape. This makes them inactive (see 1 and 2), but the amino acids remain intact. It makes no difference to your body whether the proteins in food are denatured or not -- they're all going to be broken down anyway.
6. Cooking food denatures many proteins. So does immersing them in warm, concentrated hydrochloric acid for an hour or two. Which is what the stomach does.