Before 10,000 years ago our main food source was wild animal meat, not grains. Since the birth of agriculture there has been a steady increase in the amount of grains consumed daily. 10,000 years is a very short time when you compare it to the millions of years of human evolution. Over the past 130 years in the western world where chronic disease is very widespread people have consumed a greater percentage of their calories from processed grains and gluten(Chek, 2004,64).
Many scientists believe our digestive systems have not adapted to digesting grains. Our hunter gather ancestors were taller, free of cavities, and had low infant mortality rates which indicates a nutritious diet. They also did not have the degenerative conditions we have today such as cancer, diabetes and heart disease.
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