I agree with her. All those anecdotal reports re hunter-gatherers are not terribly convincing. Much of the reports are based on hopeful beliefs in the Noble-Savage theory, nothing more. It is true, however, that HGs are physically fitter than Westerners - even I have seen that myself on a trip to Kenya.
That said, there is a huge amount of mainstream scientific evidence available online about the negative effects of cooked diets. So I can explain what benefits she can get from NOT eating cooked foods. There's nowhere near as much scientific info on the benefits of raw diets per se, just a dozen studies or so on the few benefits of a raw vegan diet(so far, most studies on raw food diets seem to be under the delusion that raw food diets are always at least 75 percent vegan with 0 to 25 percent consisting of cooked foods, including cooked animals foods). Read everything you can find online about the "Hygiene Hypothesis" theory which is now generally accepted in mainstream scientific circles , and goes on about the benefits of bacteria and parasites.
For info on the negative effects of cooked foods/cooking read the following:-
http://en.wikipedia.org/wiki/Raw_foodism#Potential_harmful_effects_of_cooked_foods_and_cookingThere are already many 1,000s of studies done on the negative effects on human health of heat-created toxins like advanced glycation end products, findable on pubmed or elsewhere. There are also some studies focus on the negative effects of nitrosamines, polyclic aromatic hydrocarbons, acrylamide and heterocyclic amines. AGEs/advanced glycation end products are particularly linked to age-related decline, so you'll age slower on a RVAF diet.
Aajonus Vonderplanitz has pointed out how food-poisoning statistics are notoriously flawed:-
http://www.karlloren.com/Diabetes/p78.htmThe real problem with food-poisoning scares is that a) many examples of "food-poisoning" concern cooked foods that have been left out too long(the combination of bacteria plus an unhealthy environment such as grainfed meats/cooked foods is really unhealthy), plus some of those foods are canned foods, being heavily preheated and b) those tiny few who do die from such foods tend overwhelmingly to be those who would have died from virtually anything else, such as very old or diseased people with bodies already destroyed by decades of cooked foods consumption and the like.