Glycemic index

Glycemic Index | Glycemic Load Chart | NU Hospitals
  • How do you define glycemic index

    The glycemic index of a food is a measure of the effect of carbohydrate on blood sugar levels.  Foods that can be broken down quickly after ingestion to release glucose into the bloodstream are considered to have high GI, while foods that are broken down slowly and release glucose gradually into bloodstream are considered to have a low glycemic index. Those with diabetes , maintaining a diet made up of low GI foods has several important health benefits.

  • Glycemic index

    (two hour blood glucose response of required food)          X 100

    Glycemic index of standard food  (glucose or white bread)

  • Glycemic load

    Glycemic load accounts for how much carbohydrates Is present in  the food and how much each gram of carbohydrates  raises blood glucose levels.

    The glycemic load of a food is calculated by multiplying the glycemic index by the amount of carbohydrates in grams provided by a food and dividing the total by 100.Dietary glycemic load is the sum of the

    glycemic load in all foods consumed in the diet.

    There are a variety of factors that can account for the glycemic index of different foods, Some of which are naturally occurring, whereas others are affected in  commercialization or home preparation.

    • Physical form : generally , the more processed  a food , the higher the GI , for example instant oatmeal has a GI of 79 whereas steel cut rolled oats has a GI of 55.
    • Food combinations: when carbohydrates foods are eaten as part of meals the GI of the meal changes based on the average of all the food had (such as red beans or legumes with rice).
    • Cooking time: longer cooking time  may increase the glycemic impact as a food by breaking down the starch or carbohydrate and allowing it to pass through the body more quickly when consumed.
    • Acidity : the more acidic a food is ( pickled food or those containing vinegar or lemon), the lower GI . for example , sourdough bread , which uses a lactobacillus or lactic acid culture as part of the leavening process, has a lower GI than white bread.
    • The fibrous coat around beans , seeds  and plant cell walls in whole grains acts a physical barrier , slowing access of
      • digestive enzymes to break down the carbohydrate, thus whole grain and legumes have a lower GI.
      • Protein/fat: adding protein or fat , which have minimal effects on glycemic

      Excursions, to a high GI food will decrease the GI of that food . for example, adding cheese to a slice of bread would decrease the GI.

      • Soluble fiber: by increasing the viscosity of the intestinal contents , the interaction between the starch and the digestive enzymes is slowed, resulting in slower and lower glycemic excursions .
      • Eventhough fatty foods such as cheese ,ghee etc are low in GI  , these cannot be included in the diet as these are high in calories and fat.

  • IMPACT OF GLYCEMIC INDEX

    • On diabetes: the foods with lower GI enters the gastrointestinal tract at the slower rate, which reduces both the glycemic response and corresponding insulin release thus reducing the risk for post prandial hyperglycemia.
    • On obesity: decreased calorie intake throughout the day after the consumption of low GI meal
    • increased the cholecystokinin (CCK) release [which are partially responsible for the sending satiety signals to the brain, thus helps in weight reduction.]
    • On Cardiac health: foods with low GI results in lowering LDL cholesterol and improved HDL cholesterol .

  • Message about glycemic index

    • Choose more fruits and vegetables.
    • Increase soluble fibre in diet.
    • Use combination of high GI foods with low GI foods.
    • Choose fewer processed foods.

  • GLYCEMIC INDEX VALUE OF FOODS

    Cereals GI values
    Ragi 86
    Cornflakes 81
     jowar 77
    wheat 72
    rice 70
    semolina 60
    Oatmeal plain 58
    Bhajra 58
    corn 56
    Sweet corn 55
    macroni 55
    Brown rice 54
    musseli 50
    vermicilli 35
    rye 34

     

    Roots and tubers GI values
    potato 70
    beetroot 64
    Sweet potato 61
    yam 51
    carrot 47
    turnip 40
    raddish 18
    onion 15

     

    pulses GI values
    Horse gram 51
    Black gram 48
    Green gram 48
    Chick peas 33
    Black eyed peas 33
    Black beans 30
    Kidney beans 29
    lentils 29
    rajmah 29
    Soya bean 18
    Brussel sprouts 16

     

    vegetables GI values
    pumpkin 75
    lettuce 16
    asparagus 15
    broculli 15
    cauliflower 15
    cucumber 15
    Egg plant 15
    beans 15
    spinach 15
    tomato 15
    cabbage 15
    mushroom 15

     

    miscellaneous GI values
    Potato chips 54
    Strawberry jam 51
    jaggery 50
    Lentil soup 44
    Custard 43
    Tomato soup 38
    Mushroom soup 27
    Celery soup 27
    Cucumber soup 27
    fructose 20

     

    Miscellaneous GI value
    maltose 105
    glucose 100
    Fruit roll 99
    Rice cake 82
    pizza 80
    wafers 76
    French fries 75
    crackers 74
    honey 73
    popcorn 72
    Corn chips 72
    bread 71
    Cranberry juice 68
    Whole wheat bread 67
    Coca-Cola 63
    Ice cream 61
    Ham burger bun 61
    sucrose 59

     

    Nuts and oils seeds GI values
    Dates fresh 103
    raisins 64
    Dates dried 42
    Apricots dried 31
    cashew 27
    peanuts 15
    Ground nuts 13

     

    Milk and milk products GI values
    Full fat milk 41
    Yogurt whole milk 36
    Semi skimmed milk 34
    Skim milk 32
    Chocolate milk 32
    soya milk 30
    whole milk 27
    Low fat sweetened tyogurt 15
    Plain yogurt 14

     

  • Reference

    • Glycemic Index and Diabetes -American Diabetes Association
    • IGNOU text book of nutrition
    • Ideas for ideai diabetic care-karnataka institute of diabetes