Sorry, you need to enable JavaScript to visit this website.

Open Menu

What Is Protein And Why Is It Important?

What Is Protein And Why Is It Important?

Protein is an important part of a healthy and balanced diet for both children and adults, but do you know what protein it is? Or why it is so important?

Most Australians get enough protein to avoid any problems with protein deficiencies —   however, the type and timing of consumption is also important.

The good news is, with a bit of planning and understanding of which high protein foods are best, it’s easy to get your protein intake right.

In this comprehensive guide, we’re going to be covering everything you need to know about protein — starting with what protein is, and why it is so important. We’re also going to be looking at what happens if you have too much or too little protein, as well as how to increase protein intake safely with a protein diet plan, if you are not meeting your protein needs.

What is protein and what does it do?

Protein is one of three main macronutrients which make up our diets (fat and carbohydrates being the other two). Macronutrients are components of food that our bodies need to provide energy and to function properly.

Protein is considered to be the building blocks of life. It can be found throughout the body — in everything from our muscles, organs, tissues and bone, to skin, hair and hormones. Protein is part of every cell in the body and plays a huge role in the everyday function of our bodies.

Protein is made up of amino acids (organic compounds made of carbon, hydrogen, nitrogen, oxygen or sulphur). There are around 20 of these amino acids in a protein all linked together to make a long chain, forming the structure of a protein. Our body uses these amino acids to maintain and build different aspects of the body or as an energy source.

Why is protein important?

Protein is incredibly important. Our bodies use protein from the food we eat to grow, build, maintain and repair body structures like bones, tissues and muscles.

Here are just some of the functions that protein plays a part in:

  • Helping to repair damaged cells and produce new cells
  • Producing components of the immune system
  • Promoting growth in children and teenagers

Without enough protein in your diet, your body can’t carry out these functions properly, which may lead to health problems.

In the sections below, we’ll go into some of the important functions in more depth.  

Protein and muscle growth

Protein helps with muscle growth and maintaining muscle mass. This is particularly important if you’re older — as we age, we lose muscle mass for various reasons. This can lead to decreased mobility, reduced fitness, weakness, and fatigue. This is why older people need to make sure they eat enough protein.

Protein can help to repair and build muscles and aid recovery after physical activity. Professional athletes tend to require much higher protein levels due to this.

Protein and bone health

Protein is thought to positively impact bone health, helping to maintain strong bones. Protein and important nutrients like calcium support growth during childhood and support bone health as we age.

Protein and weight loss

Protein can help to support you to achieve a healthy weight. This is because high protein foods leave you feeling fuller for longer, especially when compared to carbs or fats, which can improve satiety throughout the day. It is also thought to curb cravings and feelings of hunger.

Studies have also found that eating more protein has a positive effect on our metabolism, as they require more energy to digest compared to refined carbohydrates. This is known as the thermic effect of food.

How much protein should I have a day?

How much protein you need per day depends on a variety of different factors such as your age, gender, weight, overall health and activity level.

As a rough rule of thumb, approximately 0.8-1g of protein per 1kg of body weight is recommended per day.

This means the average woman needs around 55-65g of protein per day, and the average man needs around 65-85g a day.
You can use our protein intake calculator to work out how much protein you need a day, based on your gender, weight, age and level of activity.   

It’s important to stick to these rough guidelines when it comes to your protein intake — it is possible to have too much or too little protein. Doing either can have a big impact on your health and may increase the risk of health problems.

What happens if you have too much protein?

While protein is vital to ensure that our bodies can build and maintain bones, muscles and skin, it is possible to have too much protein in your diet.

As with pretty much any food type, excessive amounts of protein are not good for you. So what happens if you have too much protein?

Some of the side effects associated with a diet too high in protein may include:

  • Indigestion
  • Dehydration
  • Nausea
  • Fatigue
  • Irritability
  • Bad breath

It is a good idea to monitor your protein intake and make sure that you’re getting the right amount in your diet. Creating a protein diet plan will help you to hit your daily protein goals, while not exceeding them or hitting dangerously high levels.

What happens if you don’t eat enough protein?

Protein is responsible for lots of different functions in our body — from muscle growth and maintaining bone health, to immune function and growth in children.

Because protein plays such a pivotal role in our bodies, not getting enough protein in your diet can be damaging. This is known as a protein deficiency.

Here are some of the side effects and symptoms of protein deficiency:

  • Muscle wastage (loss of muscle mass)
  • High risk of bone fractures
  • Brittle nails
  • Hair thinning and loss
  • Skin problems such as flaky skin, depigmentation and redness
  • Stunted growth in children
  • Impaired immune function
  • Worsening of infections
  • Fatty liver and liver failure
  • Oedema (a build-up of fluids in the body, causing swelling under the skin)
  • Anaemia (the blood’s inability to deliver enough oxygen to your body’s tissues)

These effects of protein deficiency can be very serious.

It’s worth noting that protein intake has to be very low for these to occur; most people in Australia and other developed countries get enough protein in their diets to avoid the effects of true protein deficiency. This problem is more severe in developing countries in South Asia and Central Africa, particularly in children.

However, some people in Australia (such as older people or those following certain diets such as vegetarianism or veganism) are still at risk of not getting enough protein. That’s why it is so important to know what happens if you don’t eat enough protein and the possible impact this can have on your body — and to make sure that we get enough protein in our foods every day.

What is a high protein diet and what are the benefits?

Some people like to follow a high protein diet. But what is a high protein diet?

A high protein diet is a diet in which 20% or more of your total calories come from protein — though these diets can sometimes comprise as much as 30-50% protein. Typically, we tend to have 10-15% of our diet as protein.

While everyone agrees that it is important to get enough protein in our diets — at least to hit the recommended daily intake — opinions can vary on how much more protein is good for you.

There is research to suggest that, for some people, a well-balanced high protein diet can have profound health benefits.

Some of the benefits of a high protein diet (when combined with exercise including resistance training) are:

  • Increased muscle mass and strength
  • A boost in metabolism
  • Increased fat burning
  • Control and reduction of appetite and cravings
  • Weight loss
  • Lower blood pressure
  • Improved fitness
  • Faster recovery after injury
  • Maintenance of healthy bones

When followed carefully, a high protein diet plan can provide lots of health benefits and aid weight loss.

Some fad diets suggest a very high-protein diet plan can promote rapid weight loss. However, this may not be sustainable in the long term. Often these types of diets are very restrictive on the number of carbohydrates you eat and often lack the nutritional variety or dietary fibre your body needs.

As well as the other health risks this may pose, eating excessive amounts of protein won’t necessarily help you to lose weight. There is only so much protein that your body can use efficiently, and the excess amount is then excreted.

How to increase protein intake: tips and tricks

Generally speaking, we tend to get most of the protein we need to stay healthy with the average Australian diet.

However, there are some situations in which you might need to increase your protein intake. People who are pregnant or breastfeeding, teenagers, older people, or those with certain illnesses may require extra protein.

Here are some tips for how to increase protein intake easily:

  • Swap out your usual cream cheese for cottage cheese — cottage cheese is high in protein and low in fat.
  • Nuts and seeds are a great source of protein — you can add these to your breakfast (on top of yoghurt or porridge), on soups, salads and curries, or eat them as a snack between meals. Nut butter such as peanut butter is also packed with protein.
  • Eggs contain a healthy amount of protein and make a perfect protein-rich start to your day, especially when mixed with Sustagen Hospital Formula (Neutral Flavour) to make an omelette. Add smoked salmon and spinach leaves for a breakfast packed with protein.
  • Stick to lean cuts of beef or white meat like chicken or turkey instead of those with visible fat, are options for a good source of animal protein.
  • Nutritionally complete drinks such as Sustagen Hospital Formula and Sustagen Hospital Formula Plus Fibre can help to boost your daily protein intake when you don’t have time or you’re not able to cook.

Learning how to increase protein intake is easy once you know which foods are good sources. Creating an optimised protein diet plan can also help you to hit your recommended daily intake.

Creating a protein diet plan

Constructing a protein diet plan can help introduce more protein into your diet.

This can be helpful if you’re someone who needs higher levels of protein, such as a professional athlete, bodybuilder or someone who wants to build muscle, or you’re someone currently not getting enough protein.

Mapping out your meals and snacks for the week will ensure that you incorporate a more healthy amount of protein into your diet.

Here is an example of what a good protein diet plan would look like for a day:

Day 1

  • Breakfast: a three-egg egg-white omelette with salmon and spinach, and a Sustagen Hospital Formula drink (take a look at our protein at breakfast guide for more information)
  • Snack: vegetable sticks with a hummus dip
  • Lunch: grilled chicken breast and grain salad with vegetables
  • Snack: a small handful of pumpkin seeds and some cheese
  • Dinner: steak, sweet potato, broccoli and peas

It’s important to get a mix of animal-based proteins (meat and dairy) and plant-based proteins (from vegetables, nuts, seeds and pulses) throughout your day if you can.

High protein foods

There are many different high protein foods you can get your daily intake from. Some food sources of dietary protein include:

  • Eggs: whole eggs are high in protein, but egg whites carry most of the protein
  • Dairy products: milk (choose low-fat varieties), yoghurt (particularly Greek yoghurt) and cheeses like cottage cheese, parmesan and mozzarella
  • Lean meats: beef, lamb, veal, pork, kangaroo
  • Lean poultry: chicken, turkey, emu
  • Fish and seafood: fish like tuna and salmon, and seafood such as prawns, crab, lobster and mussels
  • Nuts and seeds: nuts such as almonds, cashews, pine nuts, walnuts, pistachios and hazelnuts, and seeds such as pumpkin seeds, sesame, chia, flax, sunflower seeds and quinoa
  • Pulses: beans, chickpeas, lentils, split peas
  • Soy-based products: soybeans, tofu, soy milk, tempeh

As we mentioned in the section above, it is important to eat a range of different protein sources — both animal and plant-based — to ensure that you are getting the benefits, as well as all the nutrients you need.
Nutritional supplements
Sometimes people need additional protein on top of their usual diet, or they don’t have the time to cook or sit down and eat a meal. Nutritional supplements can help if you’re looking for quick and easy ways to increase your protein intake.

There are a few different types of nutritional supplements you can use to introduce more protein into your diet, such as protein powders, shakes and bars.

Protein powders are the most common type of nutritional supplement. These can be very easily added to drinks, shakes and various recipes, making them a fast, easy and effective way to boost your protein levels.

Protein powders are either milk-based, such as whey or casein, or plant-based, such as soy, pea, hemp or peanut. Whey (a water-soluble milk protein) is the most popular protein powder, but there is a range of nutritional supplements to choose from depending on your diet and needs.

The Sustagen range offers protein-containing nutritional solutions for many dietary needs:

You can visit each page to find out more about specific nutritional supplements, or browse the complete Sustagen range to find the right nutritional supplement for your needs.

If you have any existing health conditions, it is best to check with your doctor first before you start taking any nutritional supplements, including protein.

For more information about the importance protein plays in your diet, take a look at our nutrition resources section.



Consume as part of a varied and balanced diet and healthy lifestyle. SUSTAGEN® Hospital Formula and SUSTAGEN® Hospital Formula Plus fibre are a formulated meal replacement and cannot be used as a total diet replacement. SUSTAGEN® Collagen, SUSTAGEN® Everyday and SUSTAGEN® Ready to Drink are Formulated Supplementary Foods which can be of assistance where dietary intakes of nutrients and energy may not be adequate. SUSTAGEN® OPTIMUM™ is a Food for Special Medical Purpose, specially formulated for medical conditions where nutritional needs cannot be met through diet modification alone. Must be used under the supervision of a healthcare professional. SUSTAGEN® Sport is a Formulated Supplementary Sports Food which must be consumed in conjunction with a nutritious diet, not as a sole source of nutrition and should be used in conjunction with an appropriate physical training or exercise program. Not suitable for children under 15 years of age or pregnant women. Should only be used under medical or dietetic supervision. The advice given here is intended as a general guideline only and is not intended to replace the advice of a healthcare professional. Nutritional supplements can only be of assistance where dietary intake is inadequate. Please seek advice on your individual needs from an Accredited Practicing Dietitian or your healthcare professional.