I just watched a BBC program called Did Cooking Make Us Human. Its a bit sorry what passes for science nowadays. One part of this program had a group of people in the UK eating a raw food diet for a week or so. They all ate fruits and vegetables, except the fruit was non sweet fruit like raspberries and the diet consisted mostly of raw vegetables. The people doing the test were not able to eat enough calories to satisfy themselves, eating foods like broccoli and carrots and other vegetables.

Not surprising, as those vegetables have very few calories.

There was lots of theorizing on how cooking meat made humans have a smaller gut and larger brains. No proof of this really, and in fact the one archeological site that was 1 million years old didn't have any proof of cooking or cooked meat.

This program is available to watch if you have access to high speed internet and know how to search and use torrent technology.