What is Considered Low GL? A Comprehensive Guide to Glycemic Load

A glycemic load (GL) value of 10 or less is considered low, according to the Linus Pauling Institute. This key metric provides a practical measure of how a food portion impacts blood sugar levels, accounting for both carbohydrate quality and quantity.

Quick Summary

A low glycemic load (GL) is defined as a score of 10 or below for a single serving of food. It is a practical metric that more accurately predicts blood sugar impact than the glycemic index alone by factoring in portion size.

Key Points

• Low GL Score: A glycemic load (GL) score of 10 or less per serving is considered low.

• GL vs. GI: Glycemic load is a more accurate measure than the glycemic index alone because it also accounts for typical serving sizes.

• Calculate Your GL: Use the formula GL = (GI x available carbohydrate) / 100 to determine the glycemic load of a food portion.

• Focus on Whole Foods: Prioritize minimally processed whole foods, especially fiber-rich vegetables, legumes, and fruits, to build low GL meals.

• Incorporate Protein and Healthy Fats: Combining carbohydrates with protein and fats can help lower the overall GL of a meal and improve satiety.

• Consider Cooking and Processing: Cooking methods and the level of food processing can impact GL, with less-processed and firmer-cooked foods generally having lower scores.

Understanding Glycemic Load

Glycemic Load (GL) is a more refined and practical measure than the Glycemic Index (GI) for determining a food's actual impact on your blood sugar. While GI measures how quickly a carbohydrate raises blood glucose, GL accounts for both the rate of absorption and the amount of carbohydrate in a typical serving. This distinction is crucial because a food with a high GI might have a low GL if its typical serving size contains very few carbohydrates. For example, watermelon has a high GI but a low GL due to its low carbohydrate density. Understanding what is considered low GL is essential for managing blood sugar, body weight, and reducing the risk of chronic diseases like type 2 diabetes and heart disease.

The GL Classification System

The glycemic load for a single serving of food is categorized into three ranges based on established nutritional science guidelines:

• Low GL: 10 or less
• Medium GL: 11 to 19
• High GL: 20 or more

How to Calculate Glycemic Load

The formula for calculating a food's GL is straightforward: GL = (GI x available carbohydrate (g)) / 100. Available carbohydrate is the total carbohydrate content minus the dietary fiber. For instance, a medium apple with a GI of 39 and 15g of available carbohydrates has a GL of (39 x 15) / 100 = 5.85, which falls into the low GL category. This calculation helps demystify a food's true impact on blood glucose, moving beyond just its GI number.

Benefits of Choosing Low GL Foods

A diet rich in low GL foods offers significant health advantages. By promoting a slower, steadier rise in blood sugar, these foods can lead to more stable energy levels and a reduced risk of energy crashes. For individuals with type 2 diabetes, a low GL diet can help improve glycemic control and insulin sensitivity. This approach also assists with weight management by increasing satiety and potentially encouraging fat metabolism. Furthermore, studies have shown that high GL diets are associated with an increased risk of heart disease, making a low GL diet a heart-healthy choice.

Factors That Influence a Food's Glycemic Load

The GL of a food is not fixed and can be affected by several factors:

• Fiber Content: Foods high in fiber, especially soluble fiber, tend to have a lower GL because fiber slows the digestion and absorption of carbohydrates.
• Processing: Minimally processed foods generally have a lower GL. Extensive processing can increase the rate of carbohydrate digestion, raising the GL.
• Cooking Method: The way a food is prepared can alter its GL. For instance, cooking starchy foods like pasta 'al dente' (firm) can result in a lower GI and GL than overcooking them. Cooling cooked starchy foods can also create resistant starch, which lowers the GL.
• Acidity and Ripeness: Adding acidic ingredients like vinegar or lemon juice can slow down stomach emptying and carbohydrate digestion. Similarly, unripe fruit has a lower GL than its ripe counterpart.
• Combination with Other Foods: Eating carbohydrates with fat, protein, or fiber-rich foods can lower the meal's overall GL. This is why a complete meal typically has a lower GL than eating a high-carb food alone.

Low GL Foods to Include in Your Diet

Incorporating a variety of low GL foods is key to maintaining stable blood sugar. Here is a list of excellent choices:

• Non-starchy vegetables: Broccoli, leafy greens (spinach, kale), peppers, and carrots.
• Legumes: Lentils, chickpeas, and most beans.
• Most fruits: Apples, pears, oranges, berries, and grapefruit.
• Whole grains: Oats, barley, and quinoa.
• Nuts and seeds: Peanuts, cashews, and chia seeds.
• Lean protein: Meat, poultry, fish, and eggs (GL of zero).
• Dairy: Low-fat yogurt, milk, and cheese.

GL vs. GI: A Comparison

Feature	Glycemic Index (GI)	Glycemic Load (GL)
Definition	Ranks carbohydrates based on how quickly they raise blood sugar relative to a reference food.	Measures the total impact on blood sugar, considering both GI and the portion size.
Formula	Not calculated, but measured in a lab setting by comparing a 50g carbohydrate portion to a reference.	GL = (GI x available carbohydrate (g)) / 100.
Practical Use	Useful for comparing carbohydrate quality among foods with similar serving sizes.	Offers a more realistic picture of a food's impact on blood sugar in a real-world setting.
Portion Size	Does not account for portion size.	Crucially incorporates portion size into the calculation.
Example	Watermelon has a high GI, like a doughnut.	Watermelon has a low GL, unlike a doughnut, reflecting its low carbohydrate density.

Conclusion

For those looking to manage their blood sugar, weight, or simply eat healthier, understanding what is considered low GL is an incredibly powerful tool. While the glycemic index provides useful information on carbohydrate quality, the glycemic load gives a far more accurate and practical assessment of a food's real-world effect on blood sugar levels. By prioritizing foods with a low GL—often those rich in fiber, protein, and healthy fats, and minimally processed—you can enjoy more stable energy, prolonged satiety, and a reduced risk of several chronic health conditions. Remember that other factors like ripeness and cooking methods also play a role, so a holistic approach to eating, rather than relying solely on numbers, is always best. For additional information and resources on glycemic levels, the Linus Pauling Institute is an authoritative source.

Low GL Food Options

• Non-Starchy Vegetables: Broccoli, carrots, and leafy greens are excellent choices with very low GL scores.
• Legumes: Chickpeas and lentils are staples of a low GL diet, providing ample fiber and protein.
• Whole Grains: Oats and quinoa have lower GL values than refined grains and offer lasting energy.
• Nuts and Seeds: Peanuts and cashews are low GL snacks rich in healthy fats and protein.
• Low-Fat Dairy: Skim milk and low-fat yogurt offer low GL options for protein and calcium.
• Fruits: Apples, oranges, and pears are low GL fruit options.
• Protein Sources: Meat, fish, eggs, and cheese have a GL of zero because they contain virtually no carbohydrates.

Healthy Low GL Meal Ideas

• Breakfast: Greek yogurt with berries and a sprinkle of nuts.
• Lunch: Large salad with leafy greens, chickpeas, and a lean grilled chicken breast.
• Dinner: Baked salmon with roasted broccoli and quinoa.
• Snack: An apple with a handful of almonds or a small bowl of edamame.

Conclusion

Defining what is considered low GL provides a more complete nutritional picture than relying on the glycemic index alone. With a clear understanding of how portion size affects blood sugar, individuals can make more informed food choices to benefit their health. The key is to focus on a balanced, varied diet filled with low GL foods that offer a steady release of energy and support overall well-being. By swapping high-GL choices for more nutrient-dense, low-GL alternatives like whole grains, vegetables, and legumes, one can effectively manage blood sugar and reduce the risk of associated health complications.

References

• : Glycemic Index and Glycemic Load | Linus Pauling Institute. (n.d.). https://lpi.oregonstate.edu/mic/food-beverages/glycemic-index-glycemic-load
• : Glycemic Load - an overview | ScienceDirect Topics. (n.d.). https://www.sciencedirect.com/topics/medicine-and-dentistry/glycemic-load
• : Glycemic Load and Glycemic Index | Diabetes | Illinois Extension. (n.d.). https://extension.illinois.edu/diabetes/glycemic-load-and-glycemic-index
• : Glycemic Load vs. Index: Tools for Blood Sugar Control | Verywell Health. (n.d.). https://www.verywellhealth.com/glycemic-index-vs-load-5214363
• : Low Glycemic Diet: Its Effects, What to Eat and Avoid, and More | Healthline. (n.d.). https://www.healthline.com/nutrition/low-glycemic-diet
• : Glycemic index of starchy crops and factors affecting its functionality | ScienceDirect. (n.d.). https://www.sciencedirect.com/science/article/pii/S0924224421001746

Key takeaways

• Low GL Score: A glycemic load (GL) score of 10 or less per serving is considered low.
• Portion Size Matters: Unlike the Glycemic Index (GI), GL is a more accurate measure because it includes the amount of carbohydrate consumed per portion.
• Calculation Formula: You can calculate a food's GL by multiplying its GI by the available carbohydrates per serving and dividing by 100.
• Health Benefits: A low GL diet can help manage blood sugar, aid weight loss, and reduce the risk of type 2 diabetes and heart disease.
• Food Choices: Opt for non-starchy vegetables, legumes, most fruits, nuts, and whole grains to keep your overall GL low.
• Zero GL Foods: Meat, poultry, fish, eggs, and cheese have a GL of zero, making them staples of a low GL eating plan.

FAQs

Question: What is the difference between glycemic index (GI) and glycemic load (GL)? Answer: GI ranks carbohydrates based on how quickly they raise blood sugar, while GL provides a more complete picture by also factoring in the amount of carbohydrates in a typical serving size, making it a more practical tool for everyday eating.

Question: How is a food's glycemic load calculated? Answer: Glycemic load is calculated by multiplying a food's glycemic index (GI) by its available carbohydrate content in grams per serving, and then dividing that result by 100.

Question: Are all fruits considered low GL? Answer: No. While many fruits like apples, oranges, and pears are low GL, some, such as ripe bananas or dried dates, can have a medium GL depending on the portion size. Generally, most fruits are a healthy choice.

Question: Can a food with a high glycemic index have a low glycemic load? Answer: Yes. A great example is watermelon. It has a high GI but a low GL per standard serving because it has a low carbohydrate density.

Question: How can I lower the overall GL of my meals? Answer: You can lower your meal's GL by increasing your intake of fiber, protein, and healthy fats, which slow digestion. Combining carbohydrates with these macronutrients is an effective strategy.

Question: Do cooking methods affect a food's glycemic load? Answer: Yes, cooking can affect a food's GL. Cooking starches for shorter periods, like pasta 'al dente,' can lower the GL. Cooling cooked starchy foods also lowers the GL by creating resistant starch.

Question: Why should I care about glycemic load if I don't have diabetes? Answer: Managing glycemic load is beneficial for everyone, not just people with diabetes. A low GL diet promotes more stable energy levels, supports weight management, and can reduce the risk of developing chronic diseases like type 2 diabetes and heart disease.

Frequently Asked Questions

What is the difference between glycemic index (GI) and glycemic load (GL)?

GI ranks carbohydrates based on how quickly they raise blood sugar relative to a standard, whereas GL provides a more complete picture by factoring in both the GI and the amount of carbohydrate in a typical portion, making it a more practical tool.

How is a food's glycemic load calculated?

A food's glycemic load is calculated by multiplying its glycemic index (GI) by its available carbohydrate content in grams per serving, and then dividing the result by 100.

Are all fruits considered low GL?

While many fruits like apples, oranges, and pears are low GL, some, such as ripe bananas or dried dates, can have a medium GL depending on the portion size. In general, most fruits are a healthy choice.

Can a food with a high glycemic index have a low glycemic load?

Yes. A great example is watermelon. It has a high GI but a low GL per standard serving because it has a low carbohydrate density.

How can I lower the overall GL of my meals?

You can lower your meal's GL by increasing your intake of fiber, protein, and healthy fats, which slow digestion. Combining carbohydrates with these macronutrients is an effective strategy.

Do cooking methods affect a food's glycemic load?

Yes, cooking can affect a food's GL. Cooking starches for shorter periods, like pasta 'al dente,' can lower the GL. Cooling cooked starchy foods also lowers the GL by creating resistant starch.

Why should I care about glycemic load if I don't have diabetes?

Managing glycemic load is beneficial for everyone. A low GL diet promotes more stable energy levels, supports weight management, and can reduce the risk of developing chronic diseases like type 2 diabetes and heart disease over time.