How much glycemic load is too much?

October 30, 2025 •

4 min read

According to the Linus Pauling Institute, a high glycemic load for a single food serving is considered 20 or higher. A high glycemic load diet can lead to frequent blood sugar spikes and has been linked to an increased risk of chronic diseases such as type 2 diabetes and heart disease. This article explores what constitutes a high glycemic load, its health implications, and practical strategies for maintaining a balanced diet.

Quick Summary

This guide explains the concept of glycemic load (GL) and clarifies the difference between high, medium, and low GL values. It covers the health risks associated with high GL diets and provides actionable tips for controlling your dietary GL through mindful food choices and portion control.

Key Points

High Glycemic Load (GL) Threshold: A single food item or meal with a GL of 20 or higher is considered high, while a consistent daily dietary GL above 100 may increase health risks.
Health Risks of High GL: High GL diets are linked to an increased risk of type 2 diabetes, heart disease, obesity, and certain types of cancer due to constant blood sugar spikes and insulin surges.
Manage Portion Size: Since GL depends on both food quality and quantity, limiting your portion size of high-GI foods is an effective strategy to lower your overall GL.
Combine with Other Nutrients: Pairing carbohydrates with protein, fiber, and healthy fats slows down digestion and can significantly lower a meal's total GL.
Choose Minimally Processed Foods: Whole, less-processed foods generally have a lower GL than their refined counterparts due to higher fiber content and more complex carbohydrates.
Cooking Matters: Cooking methods like boiling or cooking until al dente can help lower the GL of foods like pasta and rice by preserving their resistant starches.
Low GL for Stability: A diet with a low to moderate GL promotes more stable blood sugar, sustained energy, and can aid in weight management.

Understanding Glycemic Load Thresholds

Glycemic load (GL) is a metric that offers a more complete picture of a food's impact on blood sugar compared to the glycemic index (GI) alone. While GI only indicates how quickly carbohydrates raise blood sugar, GL also considers the quantity of carbohydrates in a typical serving. This is why a food like watermelon, despite having a high GI, results in a low GL because a standard serving contains very few carbohydrates.

For an individual food item or a meal, the glycemic load is typically categorized as follows:

High GL: 20 or higher.
Medium GL: 11 to 19.
Low GL: 10 or less.

For an entire day's diet, the Glycemic Index Foundation recommends keeping the total daily glycemic load below 100 for optimal health. A study published in Nutrition & Metabolism even suggested an optimal range of 85–100 GL per 1000 kcal to help prevent obesity and diabetes.

Health Risks of a High Glycemic Load Diet

Consistently consuming a high GL diet has been linked to a number of adverse health outcomes. When you eat high-GL foods, your body experiences a rapid spike in blood sugar, prompting the pancreas to release a large amount of insulin. Over time, this constant fluctuation can lead to serious health problems. The cycle of blood sugar spikes and insulin surges can contribute to insulin resistance, a precursor to type 2 diabetes.

Cardiovascular Disease

Multiple studies have identified a link between high GL diets and cardiovascular issues. A study of nearly 138,000 individuals found that those with high-GI diets had a greater risk of heart attacks and strokes. Other research suggests that a high GL is a risk factor for cardiovascular disease (CVD) outcomes, especially in those with pre-existing CVD or a high BMI. The chronic blood sugar and insulin spikes can also negatively impact blood lipids, blood pressure, and inflammation.

Weight Management and Obesity

The quick rise and fall of blood sugar after a high-GL meal can lead to increased cravings and overeating, which promotes weight gain. When the body is constantly exposed to high blood glucose, it can become less efficient at using it for energy, leading to more being stored as fat. Maintaining a diet with a moderate GL, as shown in the Chinese study, can lower the prevalence of overweight and obesity compared to both very high and very low GL intake.

Cancer Risk

High GL diets may increase cancer risk by affecting insulin-like growth factors. A prospective study in Italy found that high dietary GL was associated with an increased risk of colon cancer and diabetes-related cancers. While results vary depending on the type of cancer, the evidence suggests that managing your glycemic load could be a factor in long-term cancer prevention, particularly for those with a high carbohydrate intake.

Strategies for Lowering Your Glycemic Load

Managing your glycemic load involves more than just swapping out high-GI foods; it's about a holistic approach to eating that considers the overall composition of your meals.

1. Focus on Low-GI and Low-GL Carbohydrates. Opt for whole, less-processed grains like brown rice, steel-cut oats, and whole-kernel bread over refined white bread and white rice. Many fruits, vegetables, and legumes naturally fall into the low-GI and low-GL categories.

2. Don't Overlook Portion Sizes. Since GL factors in both GI and portion size, moderating how much you eat of higher-GI foods is critical. For instance, a small serving of a high-GI food like a baked potato will have a smaller impact than a very large one.

3. Combine Carbs with Protein, Fiber, and Fat. Pairing carbohydrates with these macronutrients can significantly slow down digestion and glucose absorption. Adding nuts, seeds, or a source of lean protein to a meal containing carbohydrates can help mitigate a blood sugar spike. A vinaigrette dressing on a salad can also help lower the meal's overall GL.

4. Be Mindful of Cooking Methods. How you cook your food can affect its GL. Overcooking pasta or rice breaks down the starch and increases the GI. Cooking al dente keeps the starch more resistant to digestion, resulting in a lower GL. Boiling is often better than baking or roasting, which can increase the GI of starches.

High vs. Low Glycemic Load Diet Comparison


Feature	High Glycemic Load Diet	Low Glycemic Load Diet
Food Examples	White bread, white rice, sugary drinks, instant oatmeal, baked potatoes	Whole grains, non-starchy vegetables, legumes, fruits, steel-cut oats
Blood Sugar Response	Fast and high blood sugar spikes, followed by sharp drops	Slower, more gradual, and lower rise in blood sugar
Associated Health Risks	Increased risk of type 2 diabetes, heart disease, obesity, and certain cancers	Reduced risk of type 2 diabetes and heart disease, better weight management
Insulin Impact	Frequent and large insulin surges, leading to insulin resistance over time	Stable insulin levels, helping to maintain insulin sensitivity
Satiety and Energy	Can promote cravings and overeating; energy levels fluctuate more dramatically	Promotes satiety, supports longer-lasting energy, and reduces cravings

Conclusion: Finding the Right Balance

So, how much glycemic load is too much? While the 20+ threshold for a high-GL food serving is a useful guideline, the real answer lies in your overall dietary pattern. A daily dietary GL consistently above 100 is generally considered high and is associated with increased health risks. It's not about eliminating all higher-GL foods, but rather about balancing your meals with a variety of low-GL options. Understanding the principles of glycemic load empowers you to make informed choices that can help stabilize blood sugar, manage weight, and reduce your risk for chronic diseases. By combining mindful portion control with the right food combinations, you can enjoy a balanced and health-supportive diet.

For more information on the glycemic index and load, the University of Sydney's GI website offers an extensive database for various foods.

Frequently Asked Questions

The glycemic index (GI) measures how quickly a carbohydrate-containing food raises blood sugar, while the glycemic load (GL) offers a more complete picture by also factoring in the amount of carbohydrate in a standard serving. This is why a high-GI food can have a low GL if a serving contains very few carbs.

A consistently high daily glycemic load can cause frequent and rapid blood sugar spikes, which leads to increased insulin secretion. Over time, this can contribute to insulin resistance, weight gain, and an elevated risk for developing chronic diseases like type 2 diabetes and heart disease.

Yes, you can. The key is portion control. A high-GI food can have a low GL if the serving size is small. For example, watermelon has a high GI but a low GL due to its high water and low carbohydrate content. You can also combine high-GI foods with protein, fiber, and healthy fats to lower the overall GL of a meal.

To calculate the glycemic load (GL), you use the following formula: GL = (GI x grams of available carbohydrates in one serving) / 100. This provides a numerical value for the food's real-life impact on your blood sugar.

Not necessarily. While a low-GI diet is generally beneficial for blood sugar control, it doesn't consider overall nutritional value. Some low-GI foods, like ice cream, are high in calories and unhealthy fats. Conversely, some high-GI foods, like watermelon, can be very healthy in appropriate portion sizes due to their low GL.

The way food is prepared can significantly impact its glycemic load. For instance, overcooking pasta or rice increases its GI and therefore its GL, as the starches become more easily digestible. Conversely, cooking starches like pasta until al dente or eating cooled, cooked potatoes can lower the GL.

To reduce your dietary GL, you can increase your intake of whole grains, legumes, non-starchy vegetables, and most fruits. Reduce your consumption of refined carbs like white bread and sugary drinks. Combining carbohydrates with protein and fiber, and being mindful of portion sizes are also effective strategies.