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What is Glycemic Index
If you are a health-conscious person who is pretty watchful of what all you eat and avoid, then you might be familiar with a much-hyped term called Glycemic Index (GI). So, if you're wondering - is the entire scene around this Glycemic index justified, or is it just another fad diet thing? Let's decipher the Glycemic code!
Table of Contents
What do you mean by Glycemic Index?
Glycemic Index is a grading system that classifies different carbohydrate-containing foods based on how quickly or how slowly those items can make your blood glucose levels spike. The lesser the GI numbers, the better. The reason - Low GI means a lesser impact on your blood sugar levels.
Glycemic Index Grading
- Low GI Foods: The food items with a GI score of 55 or less contain good carbohydrates. These foods break down into glucose slowly and therefore get absorbed into your blood slowly. So, having these food items will not make your blood sugar level rise abruptly.
- Medium GI Foods: The food products with a GI score between 56 to 69 are medium GI foods. These contain carbs that convert into glucose a bit faster than that of low GI foods.
- High GI Foods: A GI score of 70 and more is a bit of a red signal. These contain carbohydrates that break down into glucose quickly, making your blood sugar shoot up all of a sudden.
Comparing these scores can help you choose healthier food options.
For Example - A muffin baked using refined flour has a GI score of 75, whereas a muffin made from whole wheat has a GI of 45. So, you be the judge of which one you should prefer. Whether you want to lose weight, control diabetes, or manage any other underlying lifestyle condition, choosing the right food with the right Glycemic Index is crucial.
GI Score and its Limitations
- Glycemic Index score does not reflect the actual quantity of any given food that you would eat. It is determined in line with 100 gms of food.
- For Example - The Glycemic Index of watermelon is 80, making it a no-no fruit with high GI. However, the amount of digestible carbs in watermelon is relatively low in a standard serving. Simply put, to make our blood glucose level rise, you will have to munch on truck-loads of watermelon. How can you work through this? To accurately address this, you have to understand another term called Glycemic Load or GL. Glycemic Load is the numerical value relates to the rise in your blood glucose on eating a standard serving size.
- For Example - The GL score of 3/4th cup (120 grams) of watermelon is 5, making it a healthy food option. So, logically speaking, any food with a High GI and Low GL will NOT make your blood sugar level rise. So, you can have them without any stress.
2. It does not tell you anything about the rest of the nutritional value of a given food.
- For Example - The GI and GL of whole milk (250 ml) are 31 and 4, respectively. However, its fat content is high. Therefore, it does not make the right choice for people who are on a weight loss regimen.
Read more about sugar in watermelon
What is Glycemic Load?
Glycemic Load, or GL of food helps you understand the estimate of rise in blood glucose level after consuming it. The formula to calculate GL would be by multiplying the carb content of the food of the actual serving by the GI of the food and then dividing that value by 100.
Calculation of Glycemic Load
GL= Carb x GI / 100
1. Example - 1
Half Cup Carrot has Quantities : Carbs = 8.6 and GI = 45
So GL = 8.6 x 45 /100 = 387/100 = 3.9
Glycemic Load is 3.9
2. Example - 2
Half Cup of White Rice has Quantities: Carbs = 36 and GI = 72
So GL = 36 x 72 /100 = 2592/100 = 25.92
GL = 25.92
Frame of Reference
Use the GI and the GL system as a benchmark or a to calculate certain aspects of the food intake.
- Values Higher than 20 is considered High GL.
- Values Between 11-19 is considered Moderate GL
- Values Less than 10 is considered Low GL
Difference Between Glycemic Index and Glycemic Load
The basic premise of both these concepts is regarding the spikes they cause in the overall blood sugar levels in a person’s body. How your body will respond to what you are eating is what can be understood. This will help you whether or not you are living with diabetes.
The glycemic index value gives an insight into how the carbs consumed might affect blood sugar levels. Glycemic load, however, takes into account the components of the food on the whole. This gives a much more accurate picture of the impact the food might create on blood glucose levels. In other words, the GI will tell you how high your sugars might rise with certain foods but it may not be accurate when you actually consume the food. The idea of glycemic load will play a role here.
The GL considers – sugar and starch in the food, preparation of the food, fats, fiber, carbs, serving size, rate of absorption, digestion, etc. This holistic picture gives more accurate details.
Low Glycemic Foods for Diet
GI is a significant factor that affects the GL. If the food of a GI is lower, this means that the sugars will rise slowly after eating the food. High fiber foods and low-carb foods have a lower GI. Here are some examples of low Glycemic load food categories that can help a person with diabetes.
GL lesser than 10
- Green Peas
- Black Beans
- Non-Fat Milk
- Certain fruits like Oranges, Watermelon and Pears
GL between 11 and 19
- Rice Cakes
- Ripe Bananas
- Dried Dates
These can be good foods to consume when one wants to reduce their quantity of fat or see lesser spikes in blood sugars.
Classification of Glycemic Load follows the below pattern
Here is another chart with the GI and GL scores of some common food items
When we talk about GI, people have mixed reactions. Some call it hype, while some others think it works. Choosing food items on the basis of GI or GL can help you reverse your diabetes and manage your weight provided you choose the right food because many food items that make the typical diet for weight loss contain food with low GI values. However, researchers also warn, that regardless of if you want to lose weight, maintain weight, or control diabetes, you should not use the GI factor alone. You should also consider other nutritional requirements, such as fat, protein, vitamins, minerals, ensuring a well-balanced diet. If you're still unsure about what foods to choose or not choose, get in touch with any of our expert nutritionists for an insightful overview of the choices available to you.
1. High or Low Glycemic Index - Which is Better?
It is better to have foods with a lower glycemic index. This would mean that the food you eat will cause your blood sugars to rise slowly and not in an erratic manner creating a lesser impact on your overall HbA1c.
2. Does Rice have a Low Glycemic Index?
Rice (white rice) has a high glycemic index and it is also high in carbs and starch.
3. What are some Fruits with Low Glycemic Index?
Low GI fruits that would be healthy for consumption for a person with diabetes would be – apples, berries, orange, lemons, sweet lime, etc.
4. What are some Fruits with High Glycemic Index?
Fruits that a person with diabetes should avoid owing to a high glycemic index would be – mangoes, chikoo, sitaphal, grapes, and bananas.
This website's content is provided only for educational reasons and is not meant to be a replacement for professional medical advice. Due to individual differences, the reader should contact their physician to decide whether the material is applicable to their case.