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Visa fullständig version : Kolhydraternas betydelse för människans evolution


King Grub
2015-08-21, 11:43
We propose that plant foods containing high quantities of starch were essential for the evolution of the human phenotype during the Pleistocene. Although previous studies have highlighted a stone tool-mediated shift from primarily plant-based to primarily meat-based diets as critical in the development of the brain and other human traits, we argue that digestible carbohydrates were also necessary to accommodate the increased metabolic demands of a growing brain. Furthermore, we acknowledge the adaptive role cooking played in improving the digestibility and palatability of key carbohydrates. We provide evidence that cooked starch, a source of preformed glucose, greatly increased energy availability to human tissues with high glucose demands, such as the brain, red blood cells, and the developing fetus. We also highlight the auxiliary role copy number variation in the salivary amylase genes may have played in increasing the importance of starch in human evolution following the origins of cooking. Salivary amylases are largely ineffective on raw crystalline starch, but cooking substantially increases both their energy-yielding potential and glycemia. Although uncertainties remain regarding the antiquity of cooking and the origins of salivary amylase gene copy number variation, the hypothesis we present makes a testable prediction that these events are correlated.

The Importance of Dietary Carbohydrate in Human Evolution. Vol. 90, No. 3, September 2015.

http://www.jstor.org/stable/pdf/10.1086/682587.pdf?acceptTC=true&jpdConfirm=true

maqan
2015-08-21, 19:38
Man kanske kan tänka sig att i takt med att vi blev smartare i samband med att vi åt mer animalier lärde vi oss dessutom att laga mat och kunde tillgodogöra oss stärkelserika knölar och rötter vilket ytterligare drev vår utveckling framåt.

Nuförtiden däremot så har det nästan lett till det omvända med tanke på att vi har lärt oss att industriframställa isolerade stärkelsekällor som gör oss undernärda och fördummade :).