pa5tabear said:
Yes, I was wondering about harm not due to microbes/parasites.
It wouldn't have to induce immediate pain/discomfort though. Just because people do it doesn't mean that there aren't minor adverse effects that wouldn't be present with cooked meat.
I don't think the "digested more completely" claim is necessarily true. Evo posted a link saying that more energy is gained. This could be due to more complete digestion, but it could also be due to less energy required to break it down. You could still digest it completely (break down all component amino acids), but spend more energy doing so.
Why would raw meat produce more flatulence? I'd expect the opposite.
I agree with the rest of your post about tools, surface area, and late addition to the diet.
If energy is expended to break it down, then that energy has to be taken from the food itself. The minimum calorie intake has to include the energy required to break it down.
If energy is needed to break raw meat down, then more raw meat would be necessary to satisfy the minimum calorie intake than cooked meat. A person living on a small amount of cooked meat would starve less rapidly than a person living on the same amount of cooked meat. In times when the supply of food is low, this could make a big difference in the chances of survival.
Microbes in our gut do most of the digestion. Most of what our metabolisms used is first digested by the microbes. Aerobic microbes do a more efficient job of digesting food then anaerobic microbes. Aerobic bacteria work faster than anaerobic bacteria. Anaerobic microbes generally leave a lot of "half digested" food in the form of gases. So it is the anaerobic bacteria that leave the gas that smells.
High protein foods like meat have a lot of nitrogen compounds and sulphur compounds in them. What is left over from half digested meat is mostly carbon disulphide and ammonia. Both of them are smelly gases.
Suppose that the body doesn't expend energy to break down the raw meat. Supposing that more raw meat remains undigested than cooked meat. Or that the cooked meat is digested faster than the raw meat. The anaerobic bacteria have time to work on the proteins of the meat.
If you don't believe it, then smell the breath of a cat or dog. Dogs and cats eat a lot of meat. Furthermore, they don't use tools. They can't cut their meat into small pieces. So their ability to digest meat is somewhat compromised. Their breaths smell bad. "Doggy breath" is rather legendary. They don't care, of course.
This is from the meat. I don't know if cooking the meat would make a difference. I conjecture that it may.
Lactose intolerant people have a problem with flatulence and bloating. Undigested dairy products cause this extra gas. One of the remedies for lactose intolerance is probiotic foods and pills. Probiotic means having large amounts of aerobic bacteria. Another way to reduce gas is to take the dairy products in the form of hard cheeses. Hard cheeses have been worked on for a long time by microbes. So hard cheeses are easier to digest than milk or soft cheeses. Also, lactaid is an enzyme that breaks down lactose in milk products.
I conjecture that the lactaid and aerobic microbes that make hard cheese are doing the same job to the milk as cooking does to the meat. It breaks the material down.
This may answer the question as to why people think of hard cheese as a delicacy rather than drink milk. Most adults can't extract calories from unprocessed milk. Most adults have lost most of their ability to digest milk while growing up. Even adults that are lactose tolerant have difficulty digesting milk.. However, the calories from hard cheese can be digested even by adults.
So way back, those adults that ate hard cheese would have been at an advantage in lean times. This is why Brian said, "The cheese makers will inherit the earth" !-)
So I conjecture that raw meat causes flatulence, bloating, bad breath and starvation in lean times. Even without parasites !-)
