Understanding Diabetes and Protein

Protein plays a crucial role in our body, serving as both building blocks and fuel.² Found in muscles, organs, skin, connective tissue, blood, and even hormones like insulin, it's vital for various functions. Think of protein as a construction material made up of smaller units called amino acids. There are 20 different amino acids, each serving a specific purpose in building and maintaining our body's structures and providing energy.

There are animal proteins, and there are plant proteins.³ Each type of protein is beneficial in its own way.

Animal protein, includes milk, eggs, and meat. Animal protein is considered to have higher nutritional quality than plant-based protein because it contains a better balance of essential amino acids, is more easily digested, and helps absorb other important nutrients, such as calcium and iron. However, animal protein also contains more saturated fat and cholesterol, while plant protein has less of these and includes more fiber and other nutrients with health benefits. Indeed, eating vegetarian diets rich in minimally processed plant foods has been linked to a lower risk of developing several chronic diseases, including cardiovascular disease, diabetes, hypertension, cancer, and dementia.⁴

Ensuring a well-balanced diet rich in high-quality proteins from both plant and animal sources, including whole grains, vegetables, fruits, legumes, nuts, and seeds, can significantly enhance overall well-being and vitality.⁵

Protein is healthy and has many benefits.² It makes you feel satisfied for longer and slows down muscle mass loss, which helps maintain the body’s energy balance.²

Certain meats contain lots of fat and purine.⁶ Purine is an organic compound that, when broken down, produces uric acid. Abnormally high levels of urate in the bloodstream have been linked to obesity, type 2 diabetes, gout, and other conditions.¹

For people with kidney disease, reducing protein intake can delay the progression of the disease.³ The ideal daily protein intake for adults is around 0.8 grams per kilogram of body weight.⁷

While you should eat enough protein, you should also be mindful of what you eat. Discuss all dietary changes with a healthcare professional.

For people with diabetes, there is an additional consideration when consuming protein.^8,9 Like carbohydrates, fat and protein also affect blood glucose levels.¹ Although food with protein has a low glycemic index (meaning that it doesn’t have such a rapid or severe effect on blood glucose levels), it does make you feel less hungry afterward compared with a carbohydrate snack.² A study by the German Institute of Human Nutrition in Potsdam has also shown that a protein-rich diet can reduce long-term blood glucose levels in people with diabetes.¹⁰

Therefore, it may be advisable to perform an additional blood glucose test after a particularly high-protein meal to counter potential fluctuations in blood glucose levels. As with carbohydrates, you can inject insulin to prevent these fluctuations from occurring. Another option is to inject a suitable bolus beforehand. However, the right insulin dose is calculated differently for protein—using the “fat protein unit," or FPU for short.^11,12 However, calculating prandial insulin dosage with FPU has been associated with hypoglycemia. Consult a healthcare professional before making a fundamental change to your eating routines.

Sources:

1. Best Protein Choices for Diabetes [Internet]. American Diabetes Association. 1995-2025 [cited 2025 Jul 9]. Available from: https://diabetes.org/food-nutrition/reading-food-labels/protein
2. Andrew LaPelusa, Ravi Kaushik. Physiology, Proteins [Internet]. National Library of Medicine. 2022 [cited 2025 Jul 8]. Available from: https://www.ncbi.nlm.nih.gov/books/NBK555990/
3. Day L, Cakebread JA, Loveday SM. Food proteins from animals and plants: Differences in the nutritional and functional properties. Trends Food Sci Technol. 2022 Jan 1;119:428–42.
4. Wang T, Masedunskas A, Willett WC, Fontana L. Vegetarian and vegan diets: benefits and drawbacks. Eur Heart J. 2023 Sep 21;44(36):3423–39. 3
5. Aas AM, Axelsen M, Churuangsuk C, Hermansen K, Kendall CWC, Kahleova H, et al. Evidence-based European recommendations for the dietary management of diabetes. Diabetologia. 2023 Jun 1;66(6):965–85.
6. Choi Hyon K., Atkinson Karen, Karlson Elizabeth W., Willett Walter, Curhan Gary. Purine-Rich Foods, Dairy and Protein Intake, and the Risk of Gout in Men. N Engl J Med. 2004;350(11):1093–103.
7. Rhee CM, Wang AYM, Biruete A, Kistler B, Kovesdy CP, Zarantonello D, et al. Nutritional and Dietary Management of Chronic Kidney Disease Under Conservative and Preservative Kidney Care Without Dialysis. J Ren Nutr. 2023 Nov 1;33(6):S56–66.
8. Paterson MA, King BR, Smart CEM, Smith T, Rafferty J, Lopez PE. Impact of dietary protein on postprandial glycaemic control and insulin requirements in Type 1 diabetes: a systematic review. Diabet Med. 2019 Dec;36(12):1585–99.
9. Wolpert HA, Atakov-Castillo A, Smith SA, Steil GM. Dietary Fat Acutely Increases Glucose Concentrations and Insulin Requirements in Patients With Type 1 Diabetes. Diabetes Care. 2013 Apr 1;36(4):810–6.
10. Schüler R, Markova M, Osterhoff MA, Arafat A, Pivovarova O, Machann J, et al. Similar dietary regulation of IGF-1- and IGF-binding proteins by animal and plant protein in subjects with type 2 diabetes. Eur J Nutr. 2021 Sep;60(6):3499–504.
11. Cai Y, Li M, Zhang L, Zhang J, Su H. The effect of the modified fat-protein unit algorithm compared with that of carbohydrate counting on postprandial glucose in adults with type-1 diabetes when consuming meals with differing macronutrient compositions: a randomized crossover trial. Nutr Metab. 2023 Oct 16;20(1):43.
12. Haak T, Herrmann E, Lippmann-Grob B, Tombek A, Hermanns N, Krichbaum M. The Effect of Prandial Insulin Applied for Fat Protein Units on Postprandial Glucose Excursions in Type 1 Diabetes Patients with Insulin Pump Therapy: Results of a Randomized, Controlled, Cross- Over Study. Exp Clin Endocrinol Diabetes Off J Ger Soc Endocrinol Ger Diabetes Assoc. 2022 Apr;130(4):262–7.