The survival value of fatBecause of its efficiency as an energy store, fat has traditionally had great survival value in humans. This has been shown many times in survival situations such as shipwrecks or plane crashes. The person with the higher percentage of body fat is more likely to survive under conditions of food deprivation. The higher percentage of body fat in (pre-menopausal) females serves the biological function of helping to preserve the species in situations of famine. If women lose too much fat they become amenorrhoeic (don't ovulate and therefore do not have periods) and thus are not able to conceive. Fat is the highest source of food energy that can be obtained (9kcal/g compared with 4.5kcal/g for carbohydrate or protein), so fatty foods would have had survival value in a hunter-gatherer environment. According to Professor Kerin O'Dea from Deakin University this may explain our taste for ratty foods which still persists today. Unfortunately (or fortunately, depending on your point of view), there is now no shortage of available fat, particularly from processed foods. There is also no need to expend so much energy (and therefore 'burn off fat) by having to chase our food. So, for the first time in human history, people can overindulge their biological liking for fat, under-indulge their physical activity requirements—and get fat in the process. *14\186\4* «Generic Pharmacy» |
|
Total 1153 articles Articles © www.ipeerx.com 2012 |