The glycemic index

[Article updated on 19/09/2023]


Today this Glycemic Index is the very basis of my consultations and a good balance or rebalancing of food. This one is understood by the interlocutor, it can be easily implemented daily. It allows you to better manage your eating habits in a way to regain or maintain a healthy weight without diets restrictive, without yoyo effects and without fatigue. But he is also essential for the treatment of pathology, starting with the diabetes. Banning sugar permanently is simply not not compatible with “LIFE” that’s why we let us use this notion in the regulation of blood sugar and therefore of diabetes, overweight, etc.

Before reading on

I’m not an expert in this field, but I am passionate about nutrition and health.

The articles you’ll find on my site are the result of in-depth research that I’d like to share with you. However, I would like to stress that I am not a health professional and that my advice should in no way replace that of a qualified physician. I’m here to guide you, but it’s important that you consult a professional for specific questions or medical concerns. Your well-being is important. So be sure to consult the appropriate experts and take the best possible care of yourself.

SO what exactly is this Glycemic Index, how does it act on the body and how to use it on a daily basis?

Blood sugar in a few words:

To explain the glycemic index, you must first understand what the blood sugar.

Glycemia is the level of glucose (=sugar) in the blood. This glucose present in the bloodstream enters the body’s cells where it is used for energy production.

THE standards concerning this value are between 3.9 and 5.8 mmol/L or well 0.7 to 1.1g/L in the blood.

How does it work?

He is equally important to address the following terms to understand the rest of the explanations.

There blood sugar varies depending on our diet, our stress, of our physical activity…

If this blood sugar is too high we speak of hyperglycemia and if this is too low we speak of hypoglycemia.

This one varying, it is therefore necessary to be able to regulate it to standards physiological (3.9 and 5.8 mmol/L or 0.7 to 1.1g/L in the blood.)

There regulation of this is complex and is done by the manifestation hormones:

  • Insulin which is the hypoglycemic hormone, has the role of reducing the blood sugar.
  • THE glucagon which is the hyperglycemic hormone, you will have it Its role is to increase blood sugar levels.

THE pancreas, liver and kidney are also involved in this regulation.

THE Excess glucose is therefore stored through this whole process complex, in the form of fats in adipose cells or glycogen in muscle cells or the liver. And all this with the aim of creating energy reserves.

Examples possible variations:

During physical activity we need energy that is easy and quick to use, so we draw on blood glucose which lowers it. If this is no longer sufficient, glucagon intervenes and mobilizes glycogen reserves (created during digestion) to release glucose into the blood.

Sports activity

Other example: When we fast we are in a situation hypoglycemia, it is the same process using the glucagon which will help regulate blood sugar levels to normal physiological.

HAS the opposite when we eat, at the time of digestion we we bring into the blood: glucose which was present in the food ingested. In a normal (non-pathological) process after a meal, blood sugar rises, which stimulates the release insulin through the pancreas. This hormone promotes the entry of glucose in cells by attaching to receptors membranes present on target cells. This is how the energy reserves usable by the body when this is necessary :

  • glycogen in muscle cells or the liver
  • adipocytes: that is to say the fat cells which form the fatty mass of the body.

What is the glycemic index?

The index glycemic is defined by the capacity of a food to increase blood sugar levels during the two hours following ingestion.

All carbohydrates whether they are simple (= so-called “fast” sugars) or complex (= so-called “slow” sugars) cause a strong increased blood sugar. This peak in blood sugar occurs 30 minutes after their ingestion and is more or less large. It’s here height of this peak which will determine the glycemic index of the food.

NB: The reference is glucose which has a glycemic index equal to 100.

The index glycemic is:

  • Down when it is below 55
  • Moderate from 56 and 69
  • Pupil above 70

How does the glycemic index play a big role in a balanced diet?

A few diagrams to support the explanations can be very useful to understanding its role:

Diagram number 1:

Evolution of the glycemic index

1) Eating a food causes a rise in blood sugar as demonstrated by all the curves in diagrams n°1 and n°2. This is called postprandial hyperglycemia. (30 minutes after ingestion)

2) Insulin (hypoglycemic hormone) is secreted by the pancreas immediately after ingestion of carbohydrates. This for allow the use of glucose by cells but also to prevent hyperglycemia from lasting, sugar from remaining too much in the blood at values ​​higher than the “normal” blood sugar level. This is also demonstrated by all the curves in the diagrams n°1 and n°2

3) The higher a food has a Glycemic Index, the more it increases blood sugar and the more insulin will be secreted by the pancreas and released. The release of too much insulin following a very rapid and high rise in blood sugar can cause reactive hypoglycemia (red curve diagram n°1 and curve blue diagram n°2) and it is at this moment that the call of sugar can be felt again. This process can be carried out as many times as fast sugar with a high Glycemic Index ingested.

NB: It is from these analyzes that the sugar designations appeared “slow” and “fast” sugars

THE Fast sugars have the ability to increase strongly and quickly blood sugar after ingestion. (Red curve of diagram number 1)

THE Slow sugars have the ability to increase blood sugar levels more slowly after ingestion. (orange curve of diagram number 1)

Diagram number 2:

Blood sugar

Let’s take the example of a candy, made of pure sugar it has an Index Blood sugar equal to 100 all like glucose. Blood sugar will rise very high and quickly following ingestion of it. It will therefore be released in very large quantities into the blood. to be able to recover all the excess sugar (greater than the standards) and use it to form energy reserves: glycogen and fat cells. The amount of insulin released being very high, the blood sugar will drop below the “standards” is what we call “a reactive hypoglycemia. When we are in hypoglycemia, the appeal of sugary products is felt for resolve this one.

We we will therefore understand that beyond the aspect of addiction that causes sugar, we also have a physiological phenomenon where “Sugar calls sugar”, which is taken into account in the consumption of sweet products.

Useless to specify again that the “surplus” sugar recovered by insulin will be used for the formation of fat mass, and therefore will promote weight gain.

HAS more or less long term, the consumption of index foods high blood sugar can lead to a loss of sensitivity of insulin from the body’s cells. This “resistance” to insulin makes it lose its effectiveness and we will notice a too much sugar in the blood. Ultimately, this resistance to insulin can cause obesity, hypertension and Type 2 diabetes.

What factors cause variations in this Glycemic Index?

They lower the index glycemic of a food:

  • Fiber intake: They slow down both the rise in blood glucose and the secretion of insulin after a meal
  • Protein intake, making glucose from food less accessible for absorption.
  • The intake of lipids (= fat) also makes the glucose in foods less accessible for absorption.
  • Fats + proteins = further and significantly slow down the rate of digestion of the food, which will lower the overall Glycemic Index of the plate.
  • Al dente cooking: Starch gelatinizes when cooked in the presence of water. Gelatinized starch is more quickly transformed into glucose by digestive juices, which increases the speed of gastric emptying. The greater the gelatinization of the starch, the higher the Glycemic Index. Al dente pasta therefore has a lower Glycemic Index than overcooked, precooked or quickly cooked pasta.
Al Dente cooking

They increase the index glycemic of a food:

  • There high cooking or reheating a dish: Starch gelatinizes when cooked in the presence of water. Starch gelatinized is more quickly transformed into glucose by the juices digestive, which increases the speed of gastric emptying. More the gelatinization of the starch is important, the higher the Index Blood sugar is high. Pasta al toothed therefore have a lower Glycemic Index than pasta too cooked, pre-cooked or quick-cooked.
  • The food mixed or in the form of puree: predigested thanks to structural changes, glucose is more accessible to absorption.
  • THE refining and industrial treatments: More treatments undergone by the food are significant (kneading, cooking, conservation…), the higher the Glycemic Index will be.
  • THE ripening or hydration rate

Examples: The green banana has a Glycemic Index of 40 which increases to 65 when ripe or cooked due to gelatinization of its starch.

There raw carrot (GI 35) and cooked carrot (GI 85).

Which Glycemic Index (GI) for which food?

GI high (>70) GI moderate(between 56 and 69) GI low (< 55)
Dates 103 Apricots fresh 57 Melon 67 Cherries 63 Papaya 56 Banana very ripe 65 Figs dried 61 Grapes secs 64 Pineapple 59 Apricots with syrup 64 Peaches with syrup 58 Apple fresh 38 Apricots dry 30 Grapefruit 25 Grape 53 Banana not too ripe 52 Kiwi 53 Pear 38 Orange 42 Juice apple without added sugar 44 Juice grapefruit without added sugar 48 Juice pure orange juice 50 Juice tomato 38
Fruits oilseed
Nut pecan 10 Nut salted cashews 22 Peanuts grilled and salted 14
All vegetables have a low or even very low GI (<15) Carrots floods 16 Carrots cooked 47
Lenses dried greens cooked in water 48 Lenses coral 26 Lenses canned 48 Peas dried chickpeas cooked in water 28 Small peas 41
Soy and derivative products
Soy milk enriched with calcium 36 Yogurt with soy milk and fruit 50 Tofu (does not contain carbohydrates)
Apple earthen
Apple of baked terracotta 95 Mash potatoes instant potato 83 Apple boiled peeled earth 78 Apple of new earth with boiled skin 78 Fries 82 Apple of earth with steamed skin 65 Potato sweet cooked 46 Chips 54
Cereals and derivative products
White baguette 95 White baguette (60 g) with chocolate spread chocolate (20 g) 72 White sandwich bread 70 Wholemeal sandwich bread 71 White rusk 68 Waffles 76 Apricot LU tray 71 Kellogg’s Corn Flakes 77 Kellogg’s Corn pops 80 Kellogg’s Rice Krispies 82 Kellogg’s Smacks 71 Instant oatmeal 82 Puffed rice cakes 85 Quick-cooking rice 6 min 87 Bread complete 65 Baguette white (60 g) with butter (10 g) and raspberry jam (20 g) 62 Croissant 67 Bichoco Prince, BN 56 Flakes traditional oats 59 Special K Kellogg’s 56 Rice boiled white 64 Rice basmati 58 Gnocchi 68 polenta 68 Bread full 49 Biscuit dry little butter 50 READ Shock breakfast 42 All-Bran Kellogg’s 34 Muesli natural 49 Macaroni 47 Vermicelli 35 Spaghetti thigh. 10-15 mins 44 Wheat ebly cooking 10 min 50 Rice brown 50
Sodas, drinks
Coca-Cola 63 Fanta orange 68 Beer 66
Sugars, sweets, snack
Glucose 100 Confectioneries 78 Sugar white (sucrose) 68 Rod chocolate March 68 Chocolate with milk 64 Honey commercial mix 62 Jam 66 Fructose 10 Snickers 41 Twix 44 M&M’s 33 Syrup maple 54 Jam apricot with reduced sugar content 55 Nutella 33
Products dairy
Milk sweet concentrate 61 Low-fat fruit yogurt 26 Whole milk 27 Milk semi-skimmed 30 Ice creams 47

Okay…we must then favor foods with a low glycemic index. But how does this translate to my plate?

He All you need to do is choose the products you consume carefully. ” Either “. But it is also possible to reduce the glycemic index of a food by providing fiber and protein to their ingestion. Fiber has the power to reduce the absorption of glucose from food upon ingestion. This is represented by the green curve of diagram number 1 and the red curve of diagram number 2. Little extras of fiber: They also help to maintain glycemic balance until the next meal and allow greater satiety. The proteins being mixed to glucose during digestion also limit peaks of hyperglycemia by hindering the absorption of the molecule of glucose.

Otherwise says the perfect plate comes down to:

  • A protein portion (½ of the plate)
  • A portion of vegetables (raw or cooked) => for the fiber intake and its benefits: very few calories (1/4 of the plate minimum)
  • A portion of starchy foods (ideally whole grains or legumes for extra fiber) (1/4 of the plate)

In conclusion :

There concept of glycemic index by allowing us to act on our glycemic variations, also allows us to:

  • Control our weight either maintain or regain a healthy weight
  • To have a good balanced diet and all the benefits that come with it result: better energy, resistance to stress, better digestive comfort, better immunity, limits deficiencies, improves our psychological state: confidence in be …
  • Improve certain pathological symptoms starting with diabetes. THE type 1 diabetes (genetic) can be better managed daily while allowing small sweet pleasures.

At the house of diabetics, fruits are sometimes also banned from food, excluding a sweet product accompanied by proteins, lipids (fats), fibers will not have the same impact on blood sugar than taking this same product in isolation for example as a snack. Sweet products are therefore permitted present at the end of the meal so that the assimilation of carbohydrates is different. If a snack is necessary we will ensure that this is composed in the same way. For example: a fruit + yogurt + dried fruit. (Proteins, lipids and fibers are there)

Type 2 diabetes is caused by being overweight and therefore insulin resistance, it can also be managed in this way but the benefits will be greater: If we adapt this nutritional balance and physical activity regular (walking is one of them!), a weightloss will have the effect of making the pathology disappear.

The glycemic index, as you now know, is therefore essential in a good diet.