What is the deal with protein anyway?


OK, so we all know people in the fitness industry bang on about protein, but why? What does it do, where can we find it and why is it so important, even if you are looking for weight loss? Read on to find out more…

What is protein?

Protein in a macronutrient alongside fat and carbohydrates. Proteins are molecules made up of amino acids, some of which (essential amino acids) we need to get from food. Unlike fat and carbohydrates, the body cannot store protein so we need to ensure we are getting these effectively.

What does it do?

Protein is essential for growth and repair of body tissue and to maintain good health. It is present in every cell in the body, aids the production of enzymes and hormones and can provide us with dietary energy.

How much do I need?

Whilst the necessary intake changes throughout different points in your life, guidelines suggest 0.75g per kg body weight is sufficient for the majority of the UK population for health reasons but to change body composition (i.e. muscle to fat ratios) you would be looking anywhere between 1.8g – 2.2g per kg depending on whether you’re looking to build fat or lose muscle.

Is it important for muscle build?

Protein is essential for muscle build, alongside exercise. Not only is the correct amount required from your diet but it is required at the correct times to support muscle protein synthesis (MPS). Ideally you should be keeping your body topped up with at least 20g every 3-4 hours.

Is it important for weight loss?

The most important thing for weight loss is calories in versus calories out. That said, protein plays a vital role if you are looking at changing your body composition and can really help if you are operating in a calorie deficit for the following reasons:

It keeps you fuller for longer
At only 4kcal per gram (versus fat at 9kcal per gram), it means you can eat more for less calories and it keeps you more satisfied. When eaten alongside carbs, it can also slow down the absorption of sugar (what all carbs are converted to by the body) which can help control cravings too.

It protects your muscles
When you are in a calorie deficit and losing weight, your body loses both fat and muscle. Eating a high protein diet ensures your body burns fat in place of lean muscle ensuring you get stronger and more toned.

It burns more calories
TEF is the thermic effect of food. Protein has a higher TEF than carbs and fats i.e. it takes more energy for your body to process it than carbs and fats.

So where do I get it from?

Lots of foods contain protein, these include both;

Animal sources i.e. meat, fish, poultry, dairy and eggs. These are complete proteins and contain all the amino acids the body needs. They are referred to as having high biological value (HBV). Lean sources (i.e. more grams of protein for the calories) include chicken, turkey, tuna, white fish, shellfish, low fat dairy and egg whites. Those higher in fat include salmon, red meat, cheese, full fat dairy and egg yolks.


Non animal sources i.e. grains, nuts, seeds, plants and legumes. Not all of them contain all the amino acids your body needs – these are said to provide low biological value (LBV). To get the most of these items, it is recommended they are paired together to create complete proteins (LBV + LBV = HBV) i.e. beans and wholemeal toast, rice and beans. Sources like tofu, quinoa, chia, soy and buckwheat are however complete proteins.

What about protein powder?

Protein powder is a supplement and comes in many forms, whey, casein, rice, pea, hemp, soy and egg to name a few. Some people find it a useful and convenient tool to ensure they are hitting their protein targets each day. If it works for you great, but it shouldn’t be at the expensive of wholefoods.

So in summary, protein is really important. As a general rule, for a balanced diet, you should be aiming to have protein at every meal in some form. If a change in body composition and shape is your what you are after, it becomes even more important. Get in touch if you have any questions or would be interested in finding out about working together on an online personal training / nutrition plan to do just that.

All views are my own.