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Metabolic Health

Glycemic Index and Glycemic Load, Explained.

Written by: The Veri Team

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5 minutes

What glucose, glycemic load, and glycemic index?

‍What does it actually mean when someone’s blood sugar is high? What does the glycemic index of food indicate? What’s a glycemic load? Let’s dig into the basics of monitoring your blood sugar and how the food you eat affects your metabolic health—starting with some important terminology.

Blood glucose

Blood sugar, also known as blood glucose, is a direct result of the food you eat. Your body creates blood sugar by digesting some food into sugar that circulates in your bloodstream. Your body breaks down everything you eat and absorbs the food in its different parts including carbohydrates, proteins, fats, vitamins, and other nutrients.

The carbohydrates you consume turn into blood sugar. After you eat, your digestive system breaks down carbohydrates and turns them into glucose. Essentially, glucose is your body’s fuel source. The more carbohydrates you eat, the higher the levels of glucose you’ll have released as you digest and absorb your food[1].

Glycemic index

Glycemic index is a rating system for any food item containing carbohydrates. It represents how quickly each food item affects your blood sugar (glucose) level when it's consumed on its own.[2]

Glycemic index is ranked on a scale of 0-100 based on how quickly and how much your blood sugar levels are raised after eating that food. White bread is rapidly digested, causes substantial fluctuations in blood sugar, and thus has a high glycemic index. Whole oats, on the other hand, are digested slowly, causing a gradual rise in blood sugar and are categorized to have a low glycemic index.[2]

What determines a food’s glycemic index?

Many factors can affect a food's glycemic index, including:

Glycemic load

Not all carbs are bad. While digestible carbohydrates are absorbed into our bloodstream and increase glucose levels, fiber is one component of carbohydrates that isn’t converted into sugar. This is because it can’t be digested. However, it serves our body a host of functions, particularly in relation to our bowel movements.[2]

In order to differentiate between the two, glycemic load is used to classify foods that take into account both the amount of carbohydrates in the food in relation to its impact on blood sugar levels. Glycemic load helps you account for both the quantity and the quality of your carbs at the same time. Less than 10 is low; more than 20 is high. For a diet with a lower glycemic load, eat:

A few handy blood sugar tips

Don’t eat carbs alone; mixed-nutrient meals are better for metabolic health. Protein, fat, and fiber help slow down the digestion of carbohydrates. This will help reduce spikes in blood sugar after meals. How often you eat during the day is also important. Try to keep your blood sugar levels consistent by focusing on what, when and how much you eat.[4]

You may also want to monitor your blood sugar throughout the day—especially if someone in your family has a history of blood sugar diseases. The advent of modern technology has enabled instant results in contrast to the hours of wait that were required just a few decades back. However, continuous pricking of fingers in order to obtain blood sugar levels can lead to scarring, loss of sensibility/ perception hindrance in fingers, etc.[5]


  1. Hantzidiamantis PJ, Lappin SL. Physiology, Glucose. [Updated 2019 Aug 13]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2020 Jan-. Available from:
  2. Vega-López S, Venn BJ, Slavin JL. Relevance of the Glycemic Index and Glycemic Load for Body Weight, Diabetes, and Cardiovascular Disease. Nutrients. 2018;10(10):1361. Published 2018 Sep 22. doi:10.3390/nu10101361
  3. van Schothorst EM, Bunschoten A, Schrauwen P, Mensink RP, Keijer J. Effects of a high-fat, low- versus high-glycemic index diet: retardation of insulin resistance involves adipose tissue modulation. FASEB J. 2009;23(4):1092-1101. doi:10.1096/fj.08-117119
  4. Derdemezis CS, Lovegrove JA. Glycemic index, glycemic control and beyond. Curr Pharm Des. 2014;20(22):3620-3630. doi:10.2174/13816128113196660670
  5. Ojo O, Ojo OO, Adebowale F, Wang XH. The Effect of Dietary Glycaemic Index on Glycaemia in Patients with Type 2 Diabetes: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Nutrients. 2018;10(3):373. Published 2018 Mar 19. doi:10.3390/nu10030373

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