Raw food is all the rage these days.  What is that about?  Here is a fairly standard description:

The raw food diet is based on unprocessed and uncooked plant foods, such as fresh fruit and vegetables, sprouts, seeds, nuts, grains, beans,  dried fruit, and seaweed.

 

Heating food above 116 degrees F is believed to destroy enzymes in food that can assist in the digestion and absorption of food. Cooking is also thought to diminish the nutritional value and "life force" of food. (http://altmedicine.about.com/od/popularhealthdiets/a/Raw_Food.htm)

Here is the list of permissible foods, from the same source: 

Unprocessed, preferably organic, whole foods such as:

·         Fresh fruits and vegetables

·         Nuts

·         Seeds

·         Beans

·         Grains

·         Legumes

·         Dried fruit

·         Seaweed

·         Freshly juiced fruit and vegetables

·         Purified water

·         Young coconut milk

·         At least 75% of food consumed should not be heated over 116 degrees F.

Now if you’re going to pay attention to the semantics, raw food should also include raw animal food, such as sushi, ceviche, carpaccio, and steak tartare.  Some versions of this diet in fact include them, which I would think is a good idea as these foods give you extra protein and vitamin B₁₂.   But raw rice?  Raw beans?  

Fortunately, you don’t have to eat these straight – you can fuss with them, to make them easier on the stomach.  For example, these are some things you can do to make raw plant food more digestible and less chewy, and add variety to the diet, including:

• Sprouting seeds, grains, and beans

• Juicing fruit and vegetables

• Soaking nuts and dried fruit

• Blending

• Dehydrating

• Fermenting

From what I’ve seen, there is a huge amount of work required to follow this diet, what with the chopping, blending, dehydrating, juicing, and so forth and so on. Often, food is prepared to make it look like something it’s not – e.g. squash “spaghetti” and “mashed potatoes” made with raw cauliflower.   I can’t see this as the “correct” diet for humans, as I can’t imagine prehistoric humans doing all this stuff to raw food in order to survive.  They probably just ate the roots and berries straight .  I can understand the berries, but not the roots.  Ever try burdock straight?

As it turns out, there has been a fair amount of anthropological research done in this field.  Richard Wrangham, a professor of Biological anthropology at Harvard, is the author of a book called Catching Fire:  How Cooking Made us Human (Basic Books,  2009).  I had the pleasure of attending a lecture he gave at the Harvard Club in NYC at the invitation of my friend Janet Mindes, and found his material absolutely fascinating.  He talked about studying gorillas and chimps in the wild, in Africa, and that after a while of trudging after them, he decided he might as well eat what they ate, as that seemed to be easier and made sense.  After all, we are descended from these animals!  However, he found that in eating the monkey’s grub, roots, leaves, a few berries, and the like, whenever he got back to the camp he was ravenously hungry.  He yearned for a plate of hot mashed potatoes.  It turns out that chimps and gorillas spend about six hours per day chewing!  With some effort, modern-day humans may spend about one hour per day chewing.  Thus we have a lot of time to do other things, I would think. 

The discovery of fire, and the cooking of food, made a huge difference in the feeding of the apes. Cooking, grinding, mashing, and breaking up food  help make it softer,  and so aid greatly in digestion and absorption because these techniques allow the digestive juices to extract more nutrients from both plant and animal foods.  Professor Wrangham posits that it is cooking which made the evolutionary difference between apes and humans.  Both fire and homo erectus appeared about 1.9 million years ago.  The earlier homo habilis had larger teeth and a wider pelvis, whereas homo erectus showed a marked decrease in teeth size, a smaller pelvis and a larger skull– thus, smaller teeth and gut, bigger brain.  With the use of fire, civilization began.

Most interesting is the extensive research that shows that a cooked, soft diet  increases the absorption of both nutrients and calories. .  The calories from cooked food are more bioavailable than those of raw food, and Prof Wrangham cautions that the calories counted by the thermodynamic paradigm (which ignores the effects of cooking) should not be considered the same as the energy that is obtained from cooked food.  People who had to live in the wild on raw food became extremely gaunt and often died from malnutrition.  Women on 60-100% raw food diets lose their periods and become infertile. There are numerous stories like that throughout Wrangham’s book, and I highly recommend that anyone interested in food and health read it carefully.

And here is another interesting bit of information:  evolution supports the idea that we normally consume starch as a major part of our diet.  A 2007 paper by George Perry and Nathaniel Dominy showed that humans have many copies of the genes that allows them to produce  salivary amylase, the enzyme specifically designed to break down starches (“Diet and the evolution of human amylase gene copy number variation” - Nature Genetics 39, 1256 - 1260 (2007).   The study indicates  that individuals from populations with high-starch diets have, on average, more copies of this gene than those with traditionally low-starch diets.   As starches are most normally consumed cooked, it’s been probably the cooked, starchy foods that helped make humans what we are today.

Today’s movement emphasizing the consumption of raw foods considers these  more “natural.”   That may be true.  However, I believe that we should not quickly assume that “natural” is always good.  Poisonous mushrooms are natural too, but I don’t see anyone eating them knowingly.  Nor is there is a “right” way for humans to eat.  Most human societies eat local and seasonal foodstuffs, which vary greatly according to region.

Also, we are not like the apes:  we read books, ride bicycles, build skyscrapers, fly planes.  And we cook.  Every single group of humans that anthropology has studied has the use of fire.  So I would like to think that when food is hard to get and we need every bit of nutrition we can get our hands on, cooking our food is the ideal way to prepare it for consumption.  But in our times we have gone to the other extreme:  in the last 75-100 years or so, with commercially processed foods, we have gotten used to a very soft, finely ground diet – chopped meat, white bread, cakes, cookies, ice cream – and this diet over many years has brought us a great deal of health problems and overweight.  A raw-food diet, then, can be a very healthy and helpful approach to counterbalance the unhealthy effects of our long-term processed food diet. 

But this balance may be temporary.  The pendulum swings.  If one embarks on a raw-food diet, it’s important to pay attention and see if at any time the body says, enough!  It may be a month, a year, or seven, but a moment may come when a bowl of hot soup and some flavorful rice and beans suddenly feel just wonderful again.
 

Here is a great raw sauce good on cooked grain or fish.

SCALLION GINGER SAUCE

1 bunch scallions, white and most of the green, trimmed, finely sliced (about 1 cup)

5 thin slices of ginger, about 1 inch in diameter each, finely minced

1 clove garlic, minced

3 Tablespoons good extra virgin olive oil

1 tsp natural soy sauce

1 Tablespoon wine vinegar

Mix all ingredients in a bowl, and serve a spoonful on rice, pasta, fish, or starchy vegetables.  This keeps for several days in the fridge.  Makes 3-4 servings.