אם כבר נכנסו לנושא הזה שוב, בגלל שדיברתי על מחקרים שבדקו עדויות היסטוריות ואבולוציוניות על התנגודת לאינסולין, אז; השניים הבאים בדקו כיצד חסינות לאינסולין עזרה להשרדות, להקל על החלוקה של הגוף למקורות האנרגיה, בנוסף להסתגל למצבים בהם יש מחסור באוכל.
יש עוד כמה מחקרים שנתקלתי בהם, יותר מעניינים, אני אנסה לאתר אותם שוב.
גל.
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Eur J Clin Nutr. 2002 Mar;56 Suppl 1:S30-5. Related Articles, Links
The 'carnivore connection'--evolutionary aspects of insulin resistance.
Colagiuri S, Brand Miller J.
Department of Endocrinology, Diabetes and Metabolism, Prince of Wales Hospital, Sydney, Australia.
colagiuris@sesahs.nsw.gov.au
Insulin resistance is common and is determined by physiological (aging, physical fitness), pathological (obesity) and genetic factors. The metabolic compensatory response to insulin resistance is hyperinsulinaemia, the primary purpose of which is to maintain normal glucose tolerance. The 'carnivore connection' postulates a critical role for the quantity of dietary protein and carbohydrate and the change in the glycaemic index of dietary carbohydrate in the evolution of insulin resistance and hyperinsulinaemia.
Insulin resistance offered survival and reproductive advantages during the Ice Ages which dominated human evolution, during which a high-protein low-carbohydrate diet was consumed. Following the end of the last Ice Age and the advent of agriculture, dietary carbohydrate increased. Although this resulted in a sharp increase in the quantity of carbohydrate consumed, these traditional carbohydrate foods had a low glycaemic index and produced only modest increases in plasma insulin. The industrial revolution changed the quality of dietary carbohydrate. The milling of cereals made starch more digestible and postprandial glycaemic and insulin responses increased 2-3 fold compared with coarsely ground flour or whole grains. This combination of insulin resistance and hyperinsulinaemia is a common feature of many modern day diseases. Over the last 50 y the explosion of convenience and takeaway 'fast foods' has exposed most populations to caloric intakes far in excess of daily energy requirements and the resulting obesity has been a major factor in increasing the prevalence of insulin resistance.
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Exp Clin Endocrinol Diabetes. 1997;105 Suppl 2:54-60. Related Articles, Links
The metabolic syndrome: from inherited survival trait to a health care problem.
Colagiuri S, Brand Miller JC.
Department of Endocrinology, Diabetes and Metabolism, Prince of Wales Hospital, New South Wales, Australia.
A critical role is proposed for the quantity and quality of dietary carbohydrate in the pathogenesis of the insulin resistance and hyperinsulinaemia which characterise the Metabolic Syndrome.
We propose that an insulin-resistant genotype evolved to provide survival and reproductive advantages for the cold-climate, large game hunters of the last Ice Age who consumed a low carbohydrate, high protein diet with periodic starvation. Insulin resistance would have minimised glucose utilisation by muscles thereby facilitating the preferential utilisation of glucose by the brain, foetus and mammary gland. But beginning about 10,000 years ago following the end of the last Ice Age and the development of agriculture, dietary carbohydrate increased and the selection pressure for insulin resistance decreased in some groups. Agriculture began in the Middle East and spread throughout Europe long before it was developed elsewhere. Hence the prevalence of the insulin-resistant genotype decreased in Europeans and other groups exposed to a high carbohydrate intake for sufficiently long. Some geographically isolated groups such as the Pima Indians and Nauruans experienced conditions which further diminished the gene pool diversity and resulted in particularly insulin resistant populations. Traditional carbohydrate foods have a low glycaemic index and produce only modest increases in plasma insulin. However, the constant supply of highly refined high glycaemic index carbohydrate in modern diets, results in postprandial hyperinsulinaemia. The insulin-resistant genotype is now disadvantageous and predisposes to the development of the Metabolic Syndrome.