Protein often takes a back seat to carbohydrates in diabetes management plans because the latter (with the exception of high-fiber carbs) can drive up blood glucose levels, Similarly, fats get a lot of attention because we associate them with weight gain, which can correspond with negative metabolic effects — including progression to type 2 diabetes. But protein should not be ignored: it plays an essential role in regulating blood pressure, immune responses, hormone regulation and even glucose formation. Protein plays a role in helping to slow the rate at which glucose is released into the bloodstream, and a balanced diet that includes high-quality proteins can help with weight management. 

Protein synthesis and breakdown

Protein is in every cell in our bodies and we have over 10,000 different types. Proteins are made from a class of chemical compounds called amino acids. We don’t store amino acids in our bodies, so we either have to make them or obtain them from food. Nine of the 20 amino acids must come from food because we cannot make them; these are called essential amino acids. When we consume proteins, our bodies break them down into individual amino acids during digestion, aided by various enzymes (which are also proteins) and the gastric acid in our stomach. Once the amino acids are absorbed, our cells can begin to produce the proteins we need that help with every function of daily living. See What Is Protein?: An Essential Guide.

Protein and diabetes: Protein’s effect on blood glucose levels

During digestion, proteins break down into amino acids, which play a vital role in such processes as tissue repair and muscle synthesis. 

Although protein provides the same amount of calories per gram as carbohydrates (4cal/gram), our bodies don’t tend to utilize protein for energy because it is much easier to convert carbohydrates and fats into readily available fuel. 

Consequently, protein, by itself, doesn’t have a noticeable impact on blood glucose levels in healthy individuals. However, consuming protein in conjunction with carbohydrates can help you manage your body’s insulin response by slowing the rate at which glucose is released into your bloodstream. Learn more: 7 Simple Ways To Control Blood Sugar Spikes.

Protein’s effect on insulin

Protein has a cyclic relationship with insulin: protein is essential to creating insulin, while insulin helps a protein’s building blocks (amino acids) enter the cells that need it. 

Studies show that in healthy individuals, protein doesn’t have a significant effect on insulin sensitivity. However, research has shown mixed results in overweight and obese individuals, potentially signaling that the protein source (meaning what additional nutrients the protein is providing) might have a significant impact on insulin sensitivity. More research is needed in this area before coming to specific conclusions.

Research does, however, point to the important role that protein plays if other macronutrients like carbohydrates are either lacking or are being consumed excessively, both of which can have an impact on insulin levels. 

Ketosis, ketoacidosis  and diabetes

Low-carb (“keto”) diets have become popular over the past decade, and for some obese individuals, keto diets have proven effective. Ketogenic diets are characterized by a reduction in carbohydrates (usually to an approximate 50 grams per day) and a relative increase in the proportions of protein and fat.

Individuals with metabolic syndrome, insulin resistance and type 2 diabetes (T2D) — all diseases of carbohydrate intolerance — are likely to see symptomatic as well as objective improvements in biomarkers of disease risk if they follow a well-formulated very-low-carbohydrate diet, according to much research. Glucose control improves not only because there is less glucose coming in, but also because systemic insulin sensitivity improves as well.

However, a keto diet that is practiced to an extreme level can jeopardize health in general and for those with diabetes in particular. Humans need a minimum of 50 grams/day of carbohydrates for basic functioning. When carbohydrate intake falls below this level, insulin production decreases, which signals your body to release fatty acids stored in adipose tissue in order to provide your body with the energy it needs. These fatty acids travel from your bloodstream straight to your liver, which results in the formation of acidic compounds called ketone bodies (also known as keto-acids). Ketone bodies are produced because the brain and other cells in the central nervous system are not able to derive energy from fats. When this occurs, your body enters a state called ketosis. Risks associated with ketosis include loss of lean body mass, dehydration and electrolyte imbalance. Worse, diabetic ketosis and ketoacidosis can result: serious complications, especially for those with untreated diabetes. (If this occurs, medical attention should be sought immediately.) 

Can protein intake ameliorate the potential negative effects of a very low-carb diet? The short answer: Yes and no. If you are not getting enough carbohydrates (the primary source of energy for humans), and your blood glucose levels drop, your body can siphon amino acids (from proteins) present in body tissues or organs to form glucose, which can restabilize blood glucose levels — a process called gluconeogenesis. While protein is thus a part of this “backup response system,” and gluconeogenesis is a life-sustaining process for maintaining blood glucose levels within the physiologic range, if you have diabetes your hepatic insulin signaling can go awry and gluconeogenesis can become unabated, resulting in excessive glucose production and fasting hyperglycemia. 

Thus, it is important to ensure that you consume a modest yet appropriate amount of carbohydrates, balanced with healthy fats and high-quality proteins. Increasing protein intake or substituting carbohydrates for proteins or fats can be beneficial if these macronutrients are in an imbalance.

The benefits of regular protein consumption

Eating meals that balance high-quality proteins, fiber-rich carbohydrates and healthy fats can help people with diabetes:

• Be less controlled by hunger and stay fuller for longer
• Have a constant source of energy
• Be in better control over weight management because protein will help build muscle mass and satiety reduces overeating
• Help keep blood glucose levels in a normal range

How much protein should you eat?  

The American Diabetes Association doesn’t have a protein intake recommendation specific to those with or at risk of developing diabetes. Individuals with diabetes should use the USDA Dietary Guidelines for Americans as the ideal starting point for protein consumption: a range between 10-35% of energy intake. You can find your recommended caloric intake in Appendix 2 of the Guidelines. Here’s a brief summary:

• 1 gram of protein is 4 calories
• For a 2,000 calorie diet:
• 10% of energy = 2,000 x (.1) = 200 calories
• 35% of energy = 2,000 x (.35) = 700 calories
• To find the best range of grams of protein to consume, take the number of calories at each end of that above range and divide by 4:
• 10% of energy in protein = 200 calories/4calories per gram of protein = 25g of protein
• 35% of energy in protein = 700 calories/4calories per gram of protein = 175g of protein
• Consume protein throughout the day in relatively even amounts, which allows your body to absorb and utilize the protein as efficiently as possible

What kinds of protein are best?

See our What Is Protein: An Essential Guide for a list of high quality proteins — including nutrient-dense, lean meats that are low in saturated fats, sugars and sodium. 

Key Takeaways

Regularly consuming appropriate amounts of high-quality, nutrient-dense proteins can help with weight management and may improve the metabolic indicators critical for individuals at risk for or currently diagnosed with diabetes. Protein keeps you fuller longer than its macronutrient counterparts and refuels your body, especially following an exercise work-out. This “protein/exercise partnership” further assists with weight management, a critical factor in diabetes prevention and management. While protein on its own doesn’t greatly impact blood glucose levels or insulin responses, when consumed with carbohydrates, protein can help slow the release of glucose into the bloodstream, another attribute for those with diabetes and all of us seeking to prevent its onset.