How Dietary Carbs and Protein Affect Blood Sugar


As someone with type 2 diabetes, you’re probably more than aware of the low-carb and high-protein diets used to manage it. In our world, you’ll find a lot of people who have passionate and varying views on the inclusion of dietary carbs and protein in a diabetes-friendly diet. But what exactly are dietary carbs and protein? How do they affect blood sugar and impact overall health? Which food sources are included in either or both groups? We break it down for you here. 

What are Dietary Carbs?

Carbohydrates are a macronutrient used to help provide the body fuel for optimal body function, especially exercise. You can find carbs in the majority of food sources such as beans, bread, potatoes, cookies, pasta and more. Sometimes, carbs are also called “sugar” by people with diabetes. In type 2 diabetes, carbs converted to glucose in the blood are unable to be moved to the cells by insulin due to impaired insulin function by the pancreas.

However, carbohydrates fall into different groups which affect blood sugar differently. Some sources of carbs, such as simple refined carbs like white rice, white bread and foods high in processed and added sugars (think cookies, ice cream and candy) can raise your blood sugar much faster than carbs that are unprocessed and high in fiber. Carbs high in fiber digest slowly and keeps your blood sugar from spiking. Some foods high in carbs and fiber can also be high in protein.

Food sources of healthy carbohydrates include:

  • Barley*
  • Quinoa*
  • Oatmeal
  • Whole wheat/grain bread/pasta
  • Legumes/Beans*
  • Sweet potatoes/yams
  • Lentils*

*= High in protein

What are Dietary Proteins?

Protein is another macronutrient. It’s found everywhere in your body, even in your hair and on your skin. It’s used to maintain lean body mass and replace protein lost from the shedding of hair, skin and nails. Protein is also made from 20 amino acids, nine of which are essential and must come from food. Though individual needs differ, everyone needs to eat protein every day and some diets, like the keto diet, promote foods high in protein.

When you are eating dietary protein, you’re not just eating the protein. You’re also eating the content within it such as fats, sodium, cholesterol and depending on your diet, the carbs as well. The source of the protein matters in type 2 diabetes management. While protein doesn’t have a direct effect on blood sugar, the quality of protein can impact your risks for heart disease and the risks of developing type 2 diabetes.

For example, a Harvard study showed people who ate more red meat had a 50 percent higher risk of developing type 2 diabetes. A 20-year study showed a relationship between low-carb diets that were high in vegetable sources of fat and protein were associated in a lower risk for type 2 diabetes. So when deciding on which sources of proteins to eat, make sure the fat content also consists of good fats such as omega-3 and monounsaturated fats and minimize consumption of saturated fats. 

Dietary sources of protein include:

  • Eggs
  • Milk
  • Meat/Poultry/Pork
  • Seafood
  • Soy products
  • Nuts/seeds
  • Parmesan/Romano/Mozzarella cheeses
  • Avocado
  • Vegetables such as broccoli, edamame, peas, asparagus and artichokes

How Can I Make Sure I Get Enough Protein and Carbs in My Diet?

Understanding your diabetes management goals is essential in determining your nutrition needs. Partner with your doctor, nutritionist and diabetes educator to discuss your favorite foods and how you’d like to incorporate them into your diet, including how to determine serving and portion sizes for each meal. If you’re looking for different diets to follow, you can try diets like the Ketogenic Diet, DASH Diet and the Mediterranean Diet.

If your favorite foods are typically higher in carbs without much protein, check out Real Good Foods, where you can find tasty low-carb high protein enchiladas, pizzas, poppers and as well as low-carb high-protein recipes. Real Good Foods also breaks down how their products compare to other store-bought brands. Their products are a way for people with type 2 diabetes to eat real food without losing any flavor.


WRITTEN BY Beyond Type 2 Editorial Team, POSTED 03/27/19, UPDATED 10/11/22

This piece was authored collaboratively by the Beyond Type 2 Editorial Team.