Why is protein so important? What is protein good for? If you're one of the people who think “I know protein is good for me, but I don’t know why…and I don’t know how?” then don't worry, you’re not alone!

Sometimes the explanations can seem too technical, wordy and confusing, but this article offers a quick, simplified, and easy-to-understand list detailing the benefits of a high-protein diet. 

What is protein?

Protein makes up one-third of the holy trinity of macronutrients: carbohydrates, fats & protein. Protein is made up of amino acids, commonly known as building blocks, which play a key role in the creation and maintenance of every cell in our bodies. Protein gives tissues and organs their shape and also helps them work the way they should - it fuels our cells and powers our bodies.

In short, protein is one of the building blocks that make you into who you are.

Why is a high-protein diet good for you?

Protein is a vital macronutrient, with multiple uses in the body. Although unused calories from any source can theoretically be stored as fat, because it has so many applications, it's less likely for unused protein to be stored in this way ( 1).   This is one of the reasons why high-protein diets can be useful for weight loss and muscle growth, but let's look at some of its functions within the body(1a,2), to understand why protein is so important for overall health: 

1. Build: Protein is an important building block of bones, muscles, cartilage and skin.

2. Repair: Your body uses protein to build and repair tissue.

3. Oxygenate: Red blood cells contain a protein compound that carries oxygen throughout the body. This helps supply your entire body with the nutrients it needs.

4. Digest: About half the dietary protein that you consume each day goes into making enzymes. These are complex molecules which help to improve digestion and assist other important chemical processes in the body.

5. Regulate: Protein plays an important role in hormone regulation, especially during the transformation and development of cells during puberty.

Protein helps to build muscle

What are the benefits of protein in a healthy diet?

Protein is your best friend in any health and wellness regime. As well as the basic bodily functions outlined above, protein has a multitude of other actions which can help support your health and fitness, whether you're looking to lose weight, build muscle, or just maintain your weight and feel healthier. 

"Protein is a key nutrient in any fitness programme - a diet high in protein has major benefits for weight loss and metabolic health". Kerry Beeson BSc (Nut. Med.) Nutritional Therapist & Metabolic Balance Coach

Let's look in more detail at the variety of ways in which protein can help to positively affect your eating habits and appetite, your metabolism, and your overall health:

1. Helps build muscle mass

If you lift weights for strength, or engage in any type of training routine, protein is essential for repairing and rebuilding your muscles. As the body’s muscle fibres are made primarily of proteins, we need to consume enough dietary protein in order to properly fuel them. Eating good amounts of protein helps you maintain your muscle mass and promotes muscle growth when you do strength training ( 3, 4).

Find out how to  order high-protein muscle gain meals.

2. Reduces muscle loss

The weight we lose from dieting isn’t all body fat - unfortunately, we tend to lose some muscle as well. Research suggests that as much as 25% of weight lost by dieters is muscle mass! Luckily, protein can help you build muscle, and prevent muscle loss while dieting ( 5,6, 7). Bear in mind if you're trying to lose weight and tone up, you’ll need to build muscle - which may result in your weight increasing - so don't just rely on the scales to track your progress.

3. Keeps you fuller for longer

Protein, especially when compared to carbs and fats, helps you feel fuller with less food ( 8). This is because protein reduces levels of ghrelin, the hormone responsible for hunger. At the same time, protein boosts the levels of peptide YY, a hormone that makes you feel full ( 9, 10 , 11).Protein takes longer for our bodies to break down, and because of this, we experience slower digestion which makes us feel fuller for longer. Feeling fuller for longer keeps you away from snacking or adding in extra calories to your day! One way to add more protein is by replacing some of your carbs and fats with protein. Prep Kitchen gives you the option of opting for more protein and fewer carbs by selecting the l ower carb meal plan option.

4. Helps curb cravings

Cravings are different from a true need for food. They come from your brain, not your stomach. Cravings can be hard to control, but research shows that eating more protein can help curb these cravings- even late-night fridge raids (sound familiar?).Research has shown that increasing protein to 25% of calories reduced cravings by 60% and the desire to snack at night by half ( 12). Find out more about protein and weight loss on our blog.

Protein helps to curb cravings and keep you fuller for longer

5. Improves bone health

Getting the right amount of protein in your diet improves your bone health ( 13, 14, 15 ). Good protein consumption lowers your chance of osteoporosis - the breakdown of bone - and fractures while maintaining bone density, especially as we age. ( 16 , 17). This is an especially important benefit for women, who are at high risk of osteoporosis after menopause.

6. Boosts your immune system

Proteins aid in boosting your immune system! Proteins are made of amino acids. These compounds help turn key players in your immune system- T cells, B cells, and antibodies -into germ fighters that spot and kill harmful cells that enter your body before they can start a bacterial or viral infection. A diet low in protein leaves you open to fatigue, weakness, low immune response and impaired immune reaction ( 18 ).

7. Helps your heart

High blood pressure puts extra strain on your blood vessels, heart and other organs, such as the brain, kidneys and eyes. It can also increase the risk of some serious and potentially life-threatening health conditions, such as heart disease, heart attacks, and strokes. Interestingly, studies show that higher protein intake lowers blood pressure. In addition to lowering blood pressure, a high-protein diet also reduced LDL (bad) cholesterol and triglycerides, which lowers your risk of heart disease ( 19).

8. Boosts metabolism

Having high levels of protein in your diet boosts your metabolism, meaning that you burn more calories per day on a high-protein diet, even at rest, than you would on a lower-protein diet. That’s because your body uses calories to digest and make use of the nutrients in foods. This is referred to as the Thermic Effect of Food (TEF)- the amount of energy it takes your body to break down food. Protein has the highest thermic effect when compared to fats or carbohydrates - 20–35% compared to 5–15% - which means you're burning more calories to process the protein than you would with carbs and fats. ( 21) Find out more about the thermic effect of different foods on our blog.

High protein intake has been shown to significantly boost metabolism and increase the number of calories you burn. This can amount to 80–100 more calories burned each day ( 22,23, 24), with some research suggesting you can burn even more!

9. Helps with healing injuries

Protein is directly involved with healing wounds and injuries.  There’s a reason protein is called the building block of your body’s tissues and organs - it powers faster wound repair by reducing inflammation and creating new tissue at the site of the injury. So, eating more protein after an injury can help speed up the recovery ( 25, 26). Protein is also involved in the production of antibodies which help us to fight off infections and protect our bodies from harmful bacteria and viruses. Your cells always remember how to make these antibodies, which helps keep the immune system primed and gives us some immunity against these diseases in the future. (29)

Start feeling the benefits of protein today

Hopefully you've enjoyed reading this article, and have learned more about the many health benefits of a high-protein diet. We've seen that protein can positively impact your metabolic health, your waistline, and muscular maintenance and development. We’ve also learned how a high-protein diet keeps you feeling fuller for longer and reduces food cravings. This can be crucial when trying to lose weight within a calorie deficit and limited range of macronutrients. Find out more about how to  order high-protein meals.

It's important to note that a high-protein diet might not suit everyone, for example, it's believed that people with certain kidney disorders should not eat a diet high in protein  (27). If you have any medical conditions it's best to consult with your doctor before embarking on a very high protein diet.

You may also wish to take a look at these other related articles on our blog:

Protein and Weight Loss

How much protein do I need each day?

Can protein help support mental health

Reviewed and updated 18/6/24