The glycemic index (GI) measures how quickly a food raises blood sugar levels, while the glycemic load (GL) takes into account both the GI and the amount of carbohydrates consumed.
Foods are classified according to GI (low ≤ 55, moderate 56-69, high ≥ 70) and GC (low ≤ 10, moderate 10-20, high > 20).
Macronutrients (proteins, fats, fiber) influence the glycemic response and the rate of carbohydrate absorption. Therefore, a diet balanced in macronutrients is essential for regulating blood sugar levels. The GC is more useful than the GI for assessing the impact of foods on blood sugar levels, particularly for athletes and diabetics.
In this article, Protéalpes takes a detailed look at these different aspects.
Understanding the difference between glycemic index and glycemic load
Reminder of the glycemic index
The glycemic index (GI) ranks carbohydrates on a scale of 0 to 100 based on their ability to raise blood sugar levels.
The categories are:
- Low GI: ≤ 55
- Moderate GI: 55-70
- High GI: > 70
Pure glucose has a GI of 100. A food with a high GI rapidly increases blood sugar levels, while a food with a low GI increases them only slightly.
Regularly high blood sugar levels can lead to health problems, such as unwanted weight gain, and even type II diabetes.
However, using only the GI to choose foods is not optimal, as the overall effect also depends on the amount of carbohydrates consumed.
What is glycemic load?
The glycemic load (GL) takes into account both the glycemic index (GI) and the amount of carbohydrates in a serving.
It is calculated using the formula:
CG = (GI × carbohydrate mass)/100
The categories of CG are:
- Low CG: ≤ 10
- Moderate CG: 10-20
- High CG: > 20
The GC provides a more accurate picture of a food's impact on blood sugar levels. It is therefore clear that consuming foods with a moderate or high GI is less problematic as long as their GC remains reasonable.
The effect of macronutrients on the glycemic response
Proteins, lipids, and fiber influence the glycemic and insulinemic responses of carbohydrates, reducing the GI and GC of foods. A balanced diet in terms of macronutrients is therefore essential.
Combined effects of macronutrients on glycemic response
The glycemic response to a meal depends on the interaction between the three macronutrients: carbohydrates, proteins, and fats.
For athletes, combining protein with carbohydrates after exercise optimizes recovery and muscle glycogen synthesis. The insulin released also facilitates the transport of amino acids to the muscles.
A meal rich in protein and fat slows down gastric emptying and therefore glucose absorption, limiting the resulting spike in blood sugar levels. This provides more sustained energy.
Another concrete example: before a long period of exertion, it is advisable to avoid meals that are too high in fiber, as this would slow down digestion, which could interfere with the effort required.
For people with diabetes, the balance of carbohydrates, proteins, and fats is crucial. They should prioritize low-GI carbohydrates (vegetables, minimally processed starchy foods) and carefully combine these three macronutrients to help regulate their blood sugar levels.
This combination is called a hormonal plate. During a muscle-building phase, for example, you should aim to consume the following daily amounts spread across your different meals:
- 1.6 to 2.2 g/kg of protein
- 1.0 to 2.0 g/kg of good fats
- 4.0 to 6.0 g/kg of low GI carbohydrates
Complete example of a balanced hormonal diet
Here is an example of a balanced hormonal diet that clearly illustrates the effect of macronutrients on the glycemic response.
Let's have an evening meal consisting of:
- 120g grilled salmon (protein, omega-3)
- 150g cooked quinoa (complex carbohydrates)
- 150g steamed broccoli (fiber, minerals)
- 1 tablespoon olive oil (unsaturated fats)
- A few almonds (fats, fiber)
The proteins in salmon and the fats in olive oil slow down gastric emptying and, consequently, the absorption of glucose from quinoa. This helps limit the postprandial blood glucose spike.
In addition, the fiber in broccoli and almonds will also lower the meal’s overall glycemic index by slowing the digestion of carbohydrates. Since quinoa is a low-glycemic-index carbohydrate, it gradually releases glucose into the bloodstream.
Thus, by carefully combining protein, fat, fiber, and low-GI carbohydrates, you can create a complete and balanced meal that will produce a moderate and sustained glycemic response over time. This is the synergistic effect of macronutrients.
This type of meal is ideal in the evening for regulating blood sugar levels, promoting satiety, and optimizing recovery—whether your goal is weight loss, recovery, or muscle gain. Simply adjust the portions according to your specific needs and goals.
Organic cassava maltodextrin: glycemic load and endurance benefits
Organic cassava maltodextrin stands out for its low glycemic load compared to other maltodextrins (such as corn or potato maltodextrin).
This is due to its low dextrose equivalent (DE) of about 10.
This characteristic allows it to provide carbohydrate energy more gradually and over a longer period of time, which is a major advantage for long-duration endurance activities (>60 min). It thus helps maintain performance over time without causing a spike in blood sugar followed by a rapid drop.
In addition, because it is made from organic cassava, it naturally provides nutrients that are beneficial for athletes, such as potassium, magnesium, calcium, iron, and the antioxidant vitamin C (from added acerola). Its neutral taste also makes it easy to consume during exercise.
Impact of different types of fiber on the glycemic index and glycemic load
Dietary fiber, which is found exclusively in plants, plays a key role in lowering the glycemic index (GI) and glycemic load (GL) of foods:
- Insoluble fiber is not digested and lowers the glycemic index (GI) of foods by slowing the absorption of carbohydrates. It is found in whole grains, vegetables, and fruits.
- Soluble fiber becomes viscous when it comes into contact with water and also slows down the digestion and absorption of glucose. It is found in legumes, oats, and barley.
So, the higher a food’s fiber content, the lower its GI and GL will be. Cooking or blending foods partially breaks down the fiber and raises their GI. It is recommended to choose whole foods that are high in fiber and minimally cooked to limit blood sugar spikes.
Conclusion
We have seen that the glycemic load (GL) is a value that depends on the glycemic index (GI) and the amount of carbohydrates contained in the reference serving.
Although the GI is useful for measuring how quickly a food affects blood sugar levels, it is often better to consider the GC, which gives a better idea of its actual impact on blood sugar levels over time. Many foods, such as fruits, may have a high GI but still have a favorable GC due to their fiber content.
| 🏷️ | Difference between IG and CG |
|---|---|
| 📊 IG | Measures the rate of increase in blood sugar levels |
| 📏 Terms and Conditions | Takes into account the GI and the amount of carbohydrates |
| 🚦 Low GI | ≤ 55 |
| 🚦 Moderate IG | 55-70 |
| 🚦 High GI | > 70 |
| 🥗 Low CG | ≤ 10 |
| 🥗 Moderate CG | 10-20 |
| 🥗 High GC | > 20 |
| 🍽️ Hormonal plate | Balance of proteins, fats, and carbohydrates |
| 🥦 Fiber | Decrease the GI and GC of foods |
