wunksta wrote:Warren Dew wrote:wunksta wrote:As evidenced above, grains were eaten by humans historically.
While the article makes it sound that way, the paper proves much less. Grasses were processed by humans for some unknown purpose 30,000 years ago, yes. They might have been eaten; they might not have. Even if they were eaten, 30,000 years ago was at the end of the 2,000,000 year paleolithic period, so we wouldn't have had enough time to fully adapt to the change in diet.
What are you basing that assumption on? We have only been been drinking milk from other animals for the past few thousand years afaik, and we have evolved to adapt to that, with the majority of the population developing lactose tolerance. Humans didn't start out that way, so we had to evolve and adapt for it.
I would assume this holds true for gluten tolerance, especially considering that the majority of the population can handle it now. Which leads me to believe that we have had enough time to fully adapt to the change. I would be open to any insight you could provide on this though.
Obviously, the ability for our bodies to consume and digest it does not mean that it's healthy for us but I guess we need to determine what we mean by 'adapt'.
This is why I said "fully adapt" rather than just "adapt". Some people can digest milk sugar, true, but that doesn't mean that bovine casein doesn't cause an inflammatory response similar to gluten.
As for how I reach my conclusion, it's from looking at two factors:
- Ability to obtain energy is one of the strongest evolutionary selectors, probably an order of magnitude stronger than effects like inflammation. One would therefore expect the degree of adaptation to new energy sources like dairy lactose and grain starches would be much stronger than to other factors like inflammatory or otherwise deleterious components of plant or milk protein.
- Even this strong selection pressure for digestion of lactose and starch has only managed to drive mutations of the simplest and most common types. Adult lactose tolerance relies on disabling of a regulator region for the lactase gene which can happen though any point mutation in a region hundreds of base pairs in length; no new genetic functionality, which would take far longer to develop, is required. Likewise, the increased amylase copy number that is found in long term agricultural populations results from routine genetic recombination during meiosis, and doesn't even require a single nucleotide change. Despite how easily these mutations can occur, neither has been driven to fixation.
Given the highly important energy content in dairy and starchy agricultural products has only resulted in very limited adaptation in 10,000-30,000 years, the lower selection pressure from allergens and other low level poisons should not be expected to have resulted in any noticeable adaptation at all within the same period of time. Even slightly more sophisticated mutations, like the FOXP2 mutation in humans and neanderthals, appear to take hundreds of thousands of years to occur and become common.
I'm not trying to convince people to follow the paleo diet. If people want to eat grains as their primary calorie source, that leaves more of the good food for me.
Gotcha. I guess I was just confused on what your point of demonizing grains was. "It's bad for you" kind of makes it sound like you are trying to encourage or enlighten people on detrimental dietary habits, but if I'm mistaken I apologize.
I'm a libertarian; I have no problem with people doing detrimental things to themselves if they want.
by Share the food we have better. The USA is a grain/corn/soy based agricultural economy and we're becoming the fattest nation on earth while 'spreading the wealth' to Africa and the rest of the wold.
