When it comes to losing weight, the Glycemic Index and Glycemic Load rankings are useful tools to help you choose foods that make weight loss easier.
The Glycemix Index (GI) ranks foods according to how much they raise blood sugar levels.
The Glycemic Load (GL) ranking tells you how quickly a food causes glucose to enter the bloodstream and how much glucose you’ll get per serving.
Processed foods such as chips, pretzels, other snack foods, candy, breads, cake, and cookies have both a high GI and GL ranking.
Whole foods such as unrefined grains, non-starchy vegetables, and fruits tend to have lower GI and GL rankings.
Carbohydrates with a low GI and GL value are digested, absorbed, and metabolized more slowly than their high-GI, high-GL counterparts. They typically cause a lower and slower rise in blood glucose and, subsequently, insulin levels as well.
Controlling insulin is key to weight loss for everyone.
The Glycemic Index (GI) assigns food a score based on how drastically it makes your blood sugar rise.
Foods are ranked on a scale of 0 to 100, with pure glucose (sugar) given a value of 100.
Foods that don’t contain carbohydrates are not included on the GI. That includes beef, chicken, poultry, butter, and oils.
The lower a food’s glycemic index, the slower blood sugar rises after eating that food. In general, the more processed a food is, the higher its GI.
Conversely, the more fiber or fat in a food, the lower it’s GI.
The GI values can be broken down into three ranges.
- Low GI: 55 or less
- Medium GI: 56 to 69
- High GI: 70 to 100
For example, rice milk (a processed food without any fiber) has a high GI of 86, while brown rice (with fiber) has a medium GI of 66.
GI rankings of common foods.
High GI foods are typically packed with refined carbs and sugar.
High-fiber foods tend to have a low GI score because it takes your body longer to break them down. Sugar doesn’t rush into the bloodstream as quickly.
While GI is mainly driven by a food’s carb count, a few other factors come into play too, including:
- Ripeness (riper fruit has a higher GI)
- Cooking method (food that is cooked for longer can have a higher GI)
- What type of sugar the food contains (fructose has a lower GI than maltose, for instance)
- How processed the food is (the more processed, the higher the GI)
Knowing the GI score of some of your favorite foods can help you start making smarter choices.
If you notice most of your diet consists of high-scoring, carb-heavy picks, consider substituting with foods lower on the scale.
Look here for GI rankings of common foods.
Benefits of using the Glycemic Index to make better informed food choices.
Since it’s the carbohydrates in food that raise blood sugar, understanding GI can help you figure out which foods are best for blood sugar control.
Here are some of the benefits of following the GI list when planning your meals.
- It helps you be more mindful of your carb choices without fully restricting or severely limiting your intake.
- If you aim for a low-GI diet, you’ll naturally be focusing on whole grains, fruits, vegetables, and legumes, as opposed to the higher-GI end of the spectrum, which includes more processed foods.
- Depending on your health goals, following a GI-based diet might mean you’ll be able to rely less on standard dieting measures, such as calorie counting or regimented portion control.
- Simply being more mindful of your carb choices rather than severely limiting them can also be more sustainable in the long run.
Where the Glycemic Index falls short.
The GI of foods can actually change depending on a number of factors, which can make the measure unreliable in certain cases.
The composition of a meal can change the effect of blood sugar rise. For example, eating an apple on its own may result in a different blood glucose response than if you ate it with some peanut butter.
Protein and fat eaten together can slow carbohydrate metabolism and, therefore, result in a slower blood sugar rise.
But this brings us to a broader point: How a food specifically affects someone’s unique makeup and blood sugar varies by individual.
Meet the Glycemic Load (GL) ranking system, GI’s more specific cousin.
Where GI tells you which foods will spike your blood sugar levels more than others, the Glycemic Load (GL) tells you how quickly a food causes glucose to enter the bloodstream and how much glucose you’ll get per serving.
So instead of just having the relative GI number, GL allows you to more specifically understand how a food will affect your blood sugar levels by factoring in the number of carbs per serving.
GL foods, like GI foods, fall into three categories:
- Low GL: 10 or less
- Medium GL: 11-19
- High GL: 20 or more
For optimal health, the Glycemic Index Foundation recommends keeping your daily glycemic load under 100.
For a comparison between the GI and GL rankings of common food, check out this list.
The glycemic index tells just part of the story.
What it doesn’t tell you is how high your blood sugar could go when you actually eat the food.
To understand a food’s complete effect on blood sugar, you need to know both how quickly it drives glucose into the bloodstream and how much glucose per serving it can deliver.
The glycemic load does both — which gives you a more accurate picture of a food’s real-life impact on your blood sugar. Watermelon, for example, has a high glycemic index (80). But a serving of watermelon has so little carbohydrate that its glycemic load is only 5.
One study found that when 100 participants with poorly managed diabetes, who were on insulin or oral diabetes medications, followed a low-glycemic load diet for 10 weeks, they lost weight, lowered their cholesterol levels, and improved their A1C.
Another small randomized study found that low-glycemic-load foods, regardless of calorie restriction, were more helpful with weight loss than a diet rich in high-glycemic-load foods.
It makes sense to rely on the glycemic load because looking at the total picture of foods you eat, rather than just the individual pieces, gives you a clearer and more accurate picture of its effect on insulin levels.
Glycemic Index vs Glycemic Load: Which one should you track?
The short answer for glycemic index vs load: Check both.
If you’re trying to make smart food choices, it’s hard to get enough information from one without the other.
Try to be aware of both numbers for the foods you eat most often. This allows you to make better informed choices.
The best way to test a food’s impact on you.
The most reliable way to assess how your body is affected by certain foods is to test your blood sugar two hours after a meal.
For most people, an ideal blood sugar result is less than 180mg/dL two hours after the start of a meal. If you are not sure what your target blood sugar should be, discuss this with your physician.
In the final analysis, you are an n=1, a study of one. Each of us has a unique metabolism and we each process foods differently. Test and tweak is always my MO.
Pay attention to the Glycemic Index and Glycemic Load rankings to unlock fat stores.
These rankings are tools that can help you lose weight more easily. They are just one of the many I teach in my It’s Never Too Late Weight Loss Program.
Take me up on my offer for a FREE Strategy Call so we can discuss how you can jump start your fresh start to lose unwanted weight and keep it off.
You deserve to enjoy peace and freedom in your relationship with food, your body and your weight.
No more wondering “what if…” Schedule your FREE Strategy Call right here.
I’m looking forward to meeting you soon.
It’s Never too Late to make your weight loss journey easier. A year from now, you will thank yourself.
Please share this post with someone who might want to read this message.