What Impacts Blood Glucose Levels?


Foods that contain carbohydrates will affect blood glucose levels the most. The foods that contain the most carbohydrate include those from the Fruit Group, the Starch and Starchy Vegetable Group, and the Milk and Yogurt Group. Foods with only carbohydrate may raise blood glucose more quickly than those that also contain fat and protein. Foods that are high in carbohydrate eaten with a meal that also contains fats and protein will have a slower impact on blood glucose than those eaten alone.

How quickly and how much blood glucose levels rise depends on:

  • Food composition
  • Portion size

Food composition

Blood glucose levels are affected differently depending on whether you eat foods containing carbohydrates, proteins, fats, or a combination of these three. Carbohydrates will cause blood glucose to rise the most and the most quickly. Liquids that contain carbohydrates (like milk and juice) will cause blood glucose to rise faster than solids that contain carbohydrates (like bread). Because of the impact that they have on blood glucose levels, carbohydrates are the most important macronutrient for people with diabetes to monitor.

Portion size

The amount of food that you eat also impacts blood glucose levels. Eating more food, or bigger portions, will cause your blood glucose levels to rise more than eating smaller portions. Since carbohydrates affect blood glucose levels the most, the amount of carbohydrate that you eat each day is very important in controlling your blood glucose levels. Talk to your health care provider or dietitian about how many grams of carbohydrates you should eat each day, or what meal plan you should follow.