The glycemic index


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The glycemic index

  1. 1. The glycemicindex<br />
  2. 2. The glycemicindex<br />the prevalence of obesity has increased dramatically in a century this part and since 1997 the WHO (World Health Organization) began to consider it a real epidemic.recommendations are: 1. eat less in terms of calories2. less fat3.molta physical activity4 low-calorie dietsBUT NOT ENOUGH! <br />
  3. 3. Further improvements are however, that these dietary recommendations have not prevented the development of obesity, whose prevalence has continued to increase steadily over the past 50 years and this has not happened only in Western countries but also in developing countries and particularly in Eastern Europe, Middle East and Asia.This reason has led to many epidemiological studies in Western countries, in order to highlight any correlations between the prevalence of obesity in developed societies and some environmental factors, the results were so unexpected and surprising as to be defined un''PARADOSSO NUTRITIONAL''<br />
  4. 4. EpidemiologicStudies:<br />According to these studies, the average daily calorie consumption in Western countries over the past 50 years would be reduced by about 35% but in the same period, obesity increased by 400% in the U.S. and 300% in Europe, for example, daily caloric consumption the French, in 1960 decreased by 27,5% for men and 46% for women:IN 1935:men, women 3100kcal: 2500in 1960:Men: 2800 Women: 2300in 2003:men: 2196 women 1570 <br />there was an average decrease of 36% for the entire French population<br />
  5. 5. Results<br />This means that today we eat two times less than did our parents or grandparents in the first half of the twentieth century.Interestingly enough, the French eat on average 20% fewer calories officially recommended by nutritionists, nevertheless do not cease to gain weight!OFFICIAL RECOMMENDATIONS:IN 1980 (KCAL / DAY):MEN: WOMEN 2500: 2000The reality is that instead take: 2196 men, women 1570 kcalthe difference is: -14% for men and women: -27%<br />
  6. 6. Results<br />the results of these epidemiological studies highlight other paradoxes, for example, the highest percentage of obese people is engaged in the categories socioproffessionali more exercise in the conduct of their profession, such as farmers, artisans and housewives, conversely, between the settled population (yourself for example managers) are less obese and more than thin people.Another paradox: in countries where fat intake is lower obesity is greater, for example in South Africa where the consumption of fat represents about 22% of daily calorie supply (as opposed to the recommendation of 30%) instead of the 'body mass index (BMI) as we have seen that measures the prevalence of obesity is 59 when the figure of 25 is ideal; padassalmente Cretans consume 45% fat, compared with 30% recommended, have mass index body of 24 the figure even lower than the ideal 25.<br />
  7. 7. therefore, thanks to these epidemiological studies we can notice that there is a mismatch between the body mass of a population and its caloric, and there is not correlation with exercise, it is not totally deny the 'effect of our energy supply, but rather to admit that this is a secondary factor in weight gain. One factor that comes into play in weight gain and obesity is therefore in particular absorption gut, that is, we know that the absorption is modulated by the bioavailability of food, but we also know that the energy of the meal (in terms of calories) will be burned, is stored as fat reserves, depending on the metabolic processes induced by the nature of the food, so the metabolic process is oriented to store energy rather than burning the meal, and vice versa, and this process depends on the type of food consumed, and the type of food depends on a number of factors:1. the physical and chemical structure (formerly a type of starch for a carb, a type of fatty acid to a lipid and the type of protein)2. their possible content of fiber and soluble fiber are or their protein content and origin of these proteins4. the physical treatment<br />
  8. 8. This means that for two identical food absorption rate can be completely different and therefore trigger different metabolic reactions that lead either to burn the energy of the meal, either store it in fat reserves and then to gain weight for example, two complex carbohydrates As first the potatoes and lentils on the other, and equal understand this concept is fundamental to understand the two concepts of metabolism:A blood glucose2. insulin secretion<br />
  9. 9. Blood glucose:<br />the blood sugar is the amount of sugar glucose in the blood that is!after the night the blood sugar in the morning is about 1 gram per liter of blood.when we eat a carbohydrate (eg breakfast) this is transformed into glucose during digestion, and this therefore appears in the blood glucose by increasing glucose up to a peak<br />
  10. 10. Insulinsecretion:<br />Desmopressin is a hormone secreting pancreas: insulin, to remove glucose from the blood and store it in muscle tissue and liver (glycogen) is the response to insulin to lower blood sugar levels to restore it to its base level.the insulin response is independent of the subject, whether thin or overweight, but the answer is different, in fact a thin person esattamante the amount of insulin is proportional to the value of blood glucose, the pancreas secretes then the precise amount of insulin needed to bring down the blicemia and when the blood glucose curve returned to its base value is no more insulin in an overweight person the amount of secreted insulin to lower blood sugar levels will be disproportionate to the need, at the end of the process when the blood glucose curve was lower remains a residual amount of insulin that is called hyperinsulinism.So when insulin secretion is disproportionate part of the energy of the meal is stored as fat reserves, and hyperinsulinism is the functional cause of weight gain, and to be able to lose weight you must take action on the reduction of the insulin response reducing the blood sugar<br />