Raw vegetables are dramatically low in calories and we probably only absorb about 50 calories a pound from raw vegetables. Our caloric needs cannot be met on a raw food diet without consuming large amounts of fruits, avocado, nuts and seeds.
I wouldn’t write that in stone, yet. This is a study from, apparently, a graduate student of an anthropology professor (written in Discover Magazine, which is hardly a hotbed of accurate science). In addition, this study (I just glanced through the article), seemed hopelessly superficial — didn’t account for prior conditions, mixed too many types of foods together (meat, grains, etc) to be scientifically useful, no mention of how control groups were implemented (if any were used).
This is one reason why we must chew raw food very thoroughly. I think 30 chews was recommended by Fletcher. Pottinger did extensive experiments with cats. In one study he feed one group 100% cooked meat and milk, another 75% cooked meat and milk, and the third group 50% raw meat and milk. By the second generation the first cats were almost sterile, the second group had unhealthy kittens and by the third generation was sterile. The 1/2 raw food group was reproducing successfully into the 8th generation when the experiment was ended. They had been kept in raised cages with screening on the bottom so waste fell to the ground. The cages were removed, but a year later the ground under the first group was sterile, the 2nd batch grew a few puny weeds, but the third ground area had a rich growth of greenery.
Consequently, I try to eat about half of my food raw, and chew it thoroughly. Pasturized milk is cooked milk, but yogurt with live cultures is raw. When doing nutrition teaching, I recommend eating about 1/2 raw food. I have recently started drinking Kefir in addition to eating yogurt to improve my gut flora. I also believe we should test GMO foods in a manner similar to the cat study I described. Otherwise we have no valid answer to whether GMO food is or is not safe for large, long term consumption.