A low glycemic diet uses the glycemic index to determine which foods are less likely to impact blood sugar levels significantly. Choosing low glycemic foods may help to improve blood sugar regulation and may be beneficial for weight loss.

This article explains the glycemic index and what foods to eat and avoid.

It discusses what the research says about potential health benefits and helps someone plan a low glycemic diet.

A plate of food that has a low glycemic index, including scrambled eggs, spinach, tomatoes, fruit, and smoked salmon.Share on Pinterest
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The glycemic index (GI) is a measurement that ranks foods from 1–100 according to how much they affect a person’s blood sugar.

The guide uses pure glucose with a GI of 100 as a reference.

The Glycemic Index Foundation classify the GI of food as follows:

  • 70 or greater: High GI
  • 56-69: Medium GI
  • 55 or less: Low GI

The American Diabetes Association provide a table listing the GI totals of 62 foods. They also indicate that white bread is the reference point for the highest GI.

The glycemic index can help people to choose healthful foods that are lower in sugar and carbohydrates.

This approach might help people who want to lose weight or manage conditions such as diabetes.

Another measurement is the glycemic load., which considers the number of carbohydrates in a portion of food.

Some experts believe that the glycemic load helps give a more accurate picture of how a food raises blood sugar than GI.

Learn more about diabetes here.

According to a 2007 study, the following factors affect the GI of foods:

  • macronutrient content, including protein and fat
  • fiber content
  • types of sugar and starches
  • ripeness and maturity of the food
  • processing, preparation, and cooking methods
  • the physical form of the food
  • anti-nutrients in the food, which are substances that can block the absorption of nutrients into the body

Find out the GI of a food by referring to the International tables of glycemic index and glycemic load values 2008.

Foods to eat on a low glycemic diet include:

  • high protein foods, such as lean meat and fish
  • dairy products, such as milk and natural yogurt
  • unsweetened soy milk
  • vegetables, such as broccoli, green peas, and leafy greens
  • low-sugar fruits, such as apples, oranges, and blueberries
  • porridge made with steel-cut oats and water
  • legumes, pulses, and beans such as chickpeas, lentils, and kidney beans

Learn more about low glycemic foods here.

High GI foods include:

  • white and whole wheat bread
  • white rice
  • breakfast cereals and cereal bars
  • cakes, cookies, and sweet treats
  • high GI fruit, such as watermelon, although it has a low glycemic load
  • dried fruits such as dates, raisins, and cranberries
  • potatoes and fries
  • crisps and rice crackers
  • sweetened dairy products, such as fruit yogurts

Foods that have a medium GI of 56-69 include rye bread and raisin bran cereal. People should include medium GI foods less frequently.

Learn about the best types of bread for diabetes here.

A 2015 international scientific consensus agreed that healthful low glycemic diets could prevent and manage:

The experts suggested low glycemic diets are also important in insulin resistance and possibly some cancers.

Learn about foods that may help insulin resistance.

Weight loss

The usefulness of a low glycemic diet for weight loss is controversial.

A 2018 review reported that data are inconsistent and that positive effects on weight may be due to fiber content in foods.

However, an older 2007 Cochrane review indicated that study participants on low glycemic diets could lose up to 7 kilograms (kg) of weight and 1–2 units.

Learn how to lose weight safely here.

Diabetes

A low GI diet may be helpful for diabetes.

A 2019 review concluded that GI and glycemic load are dietary factors that likely contribute to type 2 diabetes.

The Centers for Disease Control and Prevention (CDC) suggest that people with diabetes can manage their carbohydrate intake using the glycemic index.

Learn the best way to lose weight with diabetes.

Fertility and pregnancy

One small study, consisting of 26 participants, indicated a low calorie and low glycemic diet might benefit people undergoing in vitro fertilization (IVF). The diet decreased body fat and BMI, improving pregnancy outcomes. However, scientists need to study it further.

Another study suggested that people with who eat a low GI diet have a reduced chance of excessive fetal growth, or macrosomia.

Learn about the best things to eat for gestational diabetes here.

Mood and energy

A 2016 study looked at how a high or low glycemic load diet can affect mood and energy.

Among those with a moderate weight and those with overweight, eating a diet with a high glycemic load resulted in a 38% higher score of depressive symptoms. They also had a 26% higher score for fatigue and inertia, or lack of motivation.

Those with obesity had 40% higher depression scores than those with moderate weight.

Learn about which foods might benefit depression.

It is important to note that not all low-GI foods are healthful choices.

Focusing only on low glycemic foods could mean that someone eats foods that are higher in fat or salt. For example, chocolate has a low GI content due to its high fat content.

Additionally, the GI typically focuses on how individual food items affect a person’s blood sugar levels.

People usually consume mixed meals and snacks that consist of different macronutrients, which can all affect the body’s glucose response to different foods, according to a 2017 article.

GI also does not take portion size into account.

As a result, the GI can be difficult to predict.

People should consider a low glycemic diet as part of an overall healthful eating plan.

Someone can use the MyPlate resource to help plan their meals and ensure they get the essential nutrients they need.

Learn all about micro and macronutrients here.

The keto diet and a low GI diet are entirely different. Although the GI diet focuses on rating foods that contain carbohydrates, it does not encourage a low carbohydrate diet. Instead, it aims to help people understand how eating carbohydrates can affect their blood sugar level.

The ketogenic diet is a very low carbohydrate and high fat diet. This macronutrient ratio puts to body into ketosis.

A low glycemic diet only focuses on GI rather than consuming very low levels of carbs and high levels of fat.

Low GI diets are typically higher in carbohydrates and lower in fat than keto diets.

Learn more about the keto diet here.

A low glycemic diet could be beneficial for weight loss and diabetes. It could also have positive effects on mood and energy.

Foods such as bread, cereals, and sweet treats are usually high GI. Dairy products, beans, and many fruits and vegetables are lower GI.

Someone should plan a low glycemic diet as part of an overall healthful eating plan that includes essential nutrients. A person could consult a nutrition professional to help with this.