By Steven Novella, M.D., Yale School of Medicine
Many people claim that raw food preserves the nutritious value and natural enzymes of food and that, by cooking food, you are killing the food. Eating “dead food” is not good for your health. Is raw food better for us?
Is Cooking Unnatural?
It’s true that cooking does change the chemical structure of things that are cooked, to some degree. Is cooking, therefore, making something natural into something unnatural? Is there any degree of cooking? What if we mix different ingredients together and cook them in a way that starts to combine chemicals into new structures that haven’t existed before? The point of this is to make the point that there is no real clear demarcation line between something which is entirely natural and something which is completely artificial. There is quite a fuzzy line between these two depending on the degree of alteration or processing that occurs.
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This process then could either be beneficial or harmful. For example, sometimes chemists will take a chemical structure that occurs in nature. They’ll make a slight alteration to that chemical structure to make that chemical less toxic, absorbed better, or have better bioavailability. Therefore, making it less natural is not, therefore, a bad thing.
The Raw Claim
Many people use the notion of natural being better than synthetic as a guarantee or a justification for certain lifestyle choices even though the evidence may not support those choices.
One group that takes the notion of being natural to a bit of an extreme is those who advocate eating raw food. They claim that raw food preserves the nutritious value and natural enzymes of food and that, by cooking food, you are killing the food. Eating “dead food” is not good for your health.
However, scientific evidence does not support the claims behind this. For example, there are only minimal differences in the nutritional value of food that is raw versus lightly or even moderately cooked.
In addition, the natural enzymes that occur in plant foods are plant enzymes and we don’t need them. We can make our own digestive enzymes perfectly fine. Therefore, there’s no health advantage or health benefit to the enzymes that you would find in your food.
Learn more about the common fallacies about “natural foods” you find in almost any grocery store around the world
Digestibility

What about digestibility? Some advocates of raw food claim that raw food is more digestible, that cooking it makes it harder for us to break it down and to absorb it. This claim also is not true. Some foods are easier to digest once they are cooked—meats and proteins, as well as starches. For example, a 1988 study showed that starches which are cooked are 2 to 12 times more digestible than raw starches.
Brain Development
What about the effect of cooking on brain size and population? We could take a historical view and I mean far back in history to our ancestors. The invention of cooking food correlates, in the fossil record, with a great expansion of the human brain size and population size. With cooking, we had access to much better nutrition and greater calories mainly through increased digestibility, but also by expanding the number of foods that we can eat. There are some foods that are hard to eat at all if you don’t cook them.
Therefore, the evidence shows that there are a lot of advantages to cooking. Though, some foods may be better digested if they are raw. In fact, it is recommended that you should try to include some raw fruits and vegetables in your diet or some lightly cooked or lightly steamed fruits and vegetables. It is true that extensive boiling can leach out vitamins and minerals from food. Therefore, you shouldn’t heavily boil or cook all your food.
Raw Milk

Raw milk is a claim very like raw food. Milk that has not been pasteurized is called raw milk and again proponents claim that it is more healthful because it is natural. But, the nutritional value of pasteurized milk is the same as raw milk. There does not appear to be any advantages in clinical research to raw milk in terms of taste or health. Some people may prefer the way raw milk is produced because of better treatment of animals.
Raw milk has been linked to documented disease outbreak such as E. coli and listeria. Click To TweetA 2009 review showed that there are no health benefits to raw milk. However, it did link raw milk consumption to documented disease outbreak such as E. coli and listeria, being the most common. Sanitary conditions are important and are a partial fix to this risk of bacterial outbreaks from raw milk. But, pasteurization was introduced to minimize bacterial infections and outbreaks from milk. It works for that purpose.
Common Questions About Whether Raw Food Is Better
There is much debate on the perceived superiority of raw food; however, cooking food aids in digestion and eating raw food has bacterial risks. On the other hand, raw food has more fiber and less calories and so benefits weight loss and prevents lethargy.
Cooking food destroys some vitamins such as some forms of C and B, so uncooked raw food could provide a better source for these vitamins which are innately bioavailable since they come from food and not pills.
Raw meat is eaten all over the world in the form of tartare and ceviche. Some enzymes are preserved as well as vitamin B and so could be beneficial if eaten in moderation and from a clean source and kitchen.
Raw food generally means vegetarian raw food and vegetarians statistically live longer for other reasons such as being less prone to smoke and drink in excess and exercising more, so the concept is debatable.