The role of protein in diabetes management 

By Michelle Tong, Accredited Practising Dietitian

Protein plays a critical role in maintaining metabolic health and is essential for tissue structure, enzyme function, immune defence, hormone synthesis, and cellular repair. For people living with diabetes, adequate and balanced protein intake supports glycaemic stability, satiety, muscle mass and wound healing.

Understanding amino acids  

Proteins are made up of amino acids, nine of which are essential and must be obtained from the diet. These amino acids each serve distinct physiological functions relevant to people with diabetes:

• Histidine: important for immune function and digestion.  

• Isoleucine: good for muscle metabolism, immune function, development of hemoglobin and energy regualtion.  

• Leucine: helps grow and repair muscle tissues, heal wounds and regulate blood glucose levels.   

• Lysine: Important for hormone and energy production. 

• Methionine: good for tissue growth, metabolism and absorption of essential minerals, such as zinc and selenium  

• Phenylalanine: supports the production of the brain’s chemical messengers including dopamine, epinephrine and norepinephrine.  

• Threonine: assists in the development of collagen and elastin which are important for skin and connective tissue. Threonine also plays an important role in fat metabolism and immune function.  

• Tryptophan: helps make serotonin – regulating mood, appetite and sleep. 

• Valine: encourages muscle growth, tissue regeneration and energy metabolism.  

What foods contain protein? 

Complete proteins contain all nine essential amino acids and are generally found in:

• Animal-based sources: Lean meats, poultry, fish, eggs, milk, yoghurt, cheese
• Plant-based sources: Soy products (tofu, tempeh, soy milk), quinoa, amaranth, hemp seeds

Incomplete proteins, common in plant foods, may lack one or more essential amino acids. However, when combined appropriately across the day (e.g. legumes + grains), they form complementary proteins, effectively meeting amino acid requirements.

Examples of complementary pairings:

• Wholegrain toast with peanut butter
• Hummus with wholemeal pita
• Rolled oats with chia or sunflower seeds

Importantly, it is not necessary to combine complementary proteins at every meal, provided a variety of sources are consumed across the day.

Meeting protein needs  

According to the Australian Dietary Guidelines, the primary food groups contributing protein are:

• Lean meat and alternatives: Meat, poultry, fish, eggs, legumes, tofu, nuts, seeds 

• Milk, yoghurt, cheese and/or alternatives: Preferably reduced-fat options 

Recommended average daily number of serves

	Lean meat and poultry, fish, eggs, tofu, nuts and seeds and legumes/beans			Milk, yoghurt, cheese and/or alternatives, mostly reduced fat
	19-50 Years	51-70 Years	70+ Years	19-50 Years	51-70 Years	70+ Years
Men	3	2 ½	2 ½	2 ½	2 ½	3 ½
Women	2 ½	2	2	2 ½	4	4

Serving sizes

• 65 g cooked lean meats such as beef, lamb, veal, pork, goat or kangaroo (about 90-100g raw) 
• 80g cooked lean poultry such as chicken or turkey (100g raw) 
• 100g cooked fish fillet or one small can of fish 
• 2 large eggs 
• 1 cup (150g) cooked dried beans, lentils, chickpeas, split peas or canned beans (preferably with no added salt) 
• 170g tofu 
  30g nuts, seeds, peanut or almond butter or tahini or other nut or seed paste (no added salt). 
• 250ml (1 cup) fresh, UHT long life, reconstituted powdered milk or buttermilk 
• 120ml (1/2 cup) evaporated milk 
• 200g (3/4 cup or 1 small carton) yoghurt 
• 40g (2 slices) hard cheese such as cheddar 
• 120g (1/2 cup) ricotta cheese. 

Exact protein requirements will depend on age, gender and weight.

Adults

Group	g/day	Approx. per kg body weight
Men 19–70 yrs	64g	0.84 g/kg
Men >70 yrs	81g	1.07 g/kg
Women 19–70 yrs	46g	0.75 g/kg
Women >70 yrs	57g	0.94 g/kg

Higher needs apply during illness, sarcopenia, pregnancy/lactation, or in physically active individuals.

Optimising protein intake

Ideas to increase protein intake across the day:

• Enjoy Greek yoghurt with nuts 

• Add nuts and seeds into salads  

• Add legumes to soups or casseroles  

• Eat edamame as a snack  

• Addmilk powder to soups, drinks or stews  

• Incorporate eggs into meals such as eggs on toasts, frittata, omelettes, curried eggs sandwiches 

• Enjoy a snack of hummus with freshly cut vegetables sticks  

Clinical relevance for people with diabetes

Protein is important for everything from maintaining immune function, energy production, hormones, and building strong muscles, to ongoing growth and repair. It helps reduce postprandial glucose fluctuations by slowing gastric emptying and stimulating insulin secretion.

Extra considerations for people using Ozempic or Wegovy 

Medications such as Ozempic, and Wegovy mimic the hormone that regulates appetite by slowing digestion, increasing feelings of fullness, and reducing hunger. These medications have become very popular; however, their effectiveness in reducing appetite can make it harder for people to get the nutrition they need.  

If appetite is decreased for a long period of time, an individual might miss out on essential vitamins and minerals and that can affect energy levels, metabolism, and general wellbeing. A big concern is the risk of sarcopenia, as this can affect mobility and make it harder to stay active and healthy in the long run.  

Research shows that eating more protein, especially when paired with resistance exercise like weight training, can help keep muscles strong and even support muscle gain. It can also help people continue to lose fat while keeping their metabolism working well. 

Summary

Protein is foundational to metabolic health, immune function, and muscle maintenance, all highly relevant in diabetes care. Clinicians should support individuals with diabetes to meet their protein requirements through a variety of high-quality sources, ensuring intake is tailored to age, dietary pattern, physical activity, and clinical condition.