Today I have been pondering the Protein Puzzle. Why exactly do we need protein and how does it help us with weight loss?

A common theme of food diaries is a lack of protein. So I’m constantly telling my clients they need protein to reach their fat loss goals. Despite giving advice and food plans, to a large degree clients fail to meet their suggested protein quota. Perhaps there is a lack of understanding and maybe also confusion.  So I decided to write some information why we need protein, why it is important for weight loss, and where we can get enough from.

Protein is an essential nutrient in the diet, being used to manufacture body proteins that have important structural and functional roles.

  • Structural proteins are needed to build connective tissue, cell membranes and muscle cells.
  • Regulatory proteins act as enzymes or transport vehicles.

Proteins are made up of various sequences of about 20 different amino acids. Eight of these amino acids are essential (EAAs) and must come from the diet.

why do we neeed protein

Protein is important for everyone. Protein is not just for body-builders!

Protein on its own does not lead to muscle growth. Muscle growth requires a combination of strength training and more food creating a calorie surplus.

So why do we need protein in our diet?

What is protein?
What does it do for us?
And where do we find it in our foods?

Proteins come in many different forms and have many different functions, for example:

  • Part of your DNA – your genetic inheritance! Proteins combine with nucleic acids to form nucleoproteins, in the nucleus of every cell in your body;
  • Enzymes – These are the proteins which make everything happen, e.g. to break down food for absorption; to regulate the entry of nutrients through cell walls, and the removal of waste-products; to grow, develop, move, reproduce. (Many enzymes also need specific vitamins and minerals to function);
  • Haemoglobin – the protein which, with iron, carries oxygen around your body;
  • Myoglobin and elastin – These are the two main proteins in muscle fibres;
  • Bones are mainly proteins, with calcium, magnesium and phosphate;
  • Hormones which send chemical messages between nerve cells and to regulate metabolism;
  • Antibodies which circulate in your blood to protect you against viruses;
  • Keratin which forms your hair and nails

Literally every function of your cells, organs and whole body is controlled by proteins. They are all made within the body from smaller molecules which ultimately have come from foods. None of our body proteins arrives ready made.

So why do I go on at you about increasing your protein intake?

Protein Can Help You Lose Weight

Protein is incredibly important when it comes to losing weight. As we know… In order to lose weight, we need to take in fewer calories than we burn.  Eating protein can help with that, by boosting your metabolic rate (calories out) and reducing your appetite (calories in). This is well supported by science.

Protein at around 25-30% of calories has been shown to boost metabolism by up to 80 to 100 calories per day, compared to lower protein diets.

But probably the most important contribution of protein to weight loss, is its ability to reduce appetite and cause a spontaneous reduction in calorie intake. Protein is much more satiating than both fat and carbohydrates.

In a study in obese men, protein at 25% of calories increased feelings of fullness, reduced the desire for late-night snacking by half and reduced obsessive thoughts about food by 60%.

In another study, women who increased protein intake to 30% of calories ended up eating 441 fewer calories per day. They also lost 11 pounds in 12 weeks, just by adding more protein to their diet.

According to studies, a protein intake around 30% of calories may be optimal for weight loss.
This amounts to 150 grams per day for someone on a 2000 calorie diet.

Bottom Line: A protein intake at around 30% of calories seems to be optimal for weight loss. It boosts the metabolic rate and causes a spontaneous reduction in calorie intake.

But protein doesn’t just help you lose weight
It can also help prevent you from gaining weight in the first place.

A high protein intake also helps to build and preserve muscle mass (see below), which burns a small amount of calories around the clock. By eating more protein, you will make it much easier to stick to whichever weight loss plan you choose to follow.

How much protein do I need?

need protein

There are vastly different opinions on how much protein we actually need. Most official nutrition organizations recommend a fairly modest protein intake. The DRI (Dietary Reference Intake) is 0.8 grams of protein per kilogram of body weight.

This amounts to

  • 56 grams per day for the average sedentary man.
  • 46 grams per day for the average sedentary woman.

Although this meagre amount may be enough to prevent downright deficiency, studies show that it is far from sufficient to ensure optimal health and body composition.

It turns out that the “right” amount of protein for any one individual depends on many factors including

  • activity levels
  • age
  • muscle mass
  • physique goals
  • current state of health.

So… what amount of protein is optimal and how do lifestyle factors like weight loss, muscle building and activity levels factor in?  Let’s find out…

More Protein Can Help You Gain Muscle and Strength

why do we need protein

Muscles are made largely of protein.  As with most tissues in the body, muscles are dynamic and are constantly being broken down and rebuilt. To gain muscle, the body must be synthesising more muscle protein than it is breaking down.

In other words, there needs to be a net positive protein balance (often called nitrogen balance, because protein is high in nitrogen) in the body.  For this reason, people who want a lot of muscle will need to eat a greater amount of protein (and lift heavy things, of course). It is well documented that a higher protein intake helps build muscle and strength.

Also, people who want to hold on to muscle that they’ve already built may need to increase their protein intake when losing body fat, because a high protein intake can help prevent the muscle loss that usually occurs when dieting.

A common recommendation for gaining muscle is 2.2 grams of protein per kg bodyweight.


If you’re carrying a lot of body fat, then it is a good idea to use either your lean mass or your goal weight, instead of total body weight, because it’s mostly your lean mass that determines the amount of protein you need.

Bottom Line: It is important to eat enough protein if you want to gain and/or maintain muscle. Most studies suggest that 1.5 – 2.2 grams per kg bodyweight is sufficient.

Other Circumstances That Can Increase Protein Needs

Disregarding muscle mass and physique goals, people who are physically active do need more protein than people who are sedentary.  If you have a physically demanding job, you walk a lot, run, swim or do any sort of exercise, then you need more protein. Endurance athletes also need quite a bit of protein, about 1.2 – 1.4 grams per kg.

Elderly people also need significantly more protein, up to 50% higher than the DRI.This can help prevent osteoporosis and sarcopenia (reduction in muscle mass), both significant problems in the elderly.

People who are recovering from injuries may also need more protein.

Bottom Line: Protein requirements are significantly increased in people who are physically active, as well as in elderly individuals and people who are recovering from injuries.

Does Protein Have any Negative Health Effects?

why do we need protein

Protein has been unfairly blamed for a number of health problems.  It has been said that a high protein diet can cause kidney damage and osteoporosis.  However, none of this is supported by science.

Although protein restriction is helpful for people with pre-existing kidney problems, protein has never been shown to cause kidney damage in healthy people. In fact, a higher protein intake has been shown to lower blood pressure and help fight diabetes, which are two of the main risk factors for kidney disease.  If protein really does have some detrimental effect on kidney function (which has never been proven), it is outweighed by the positive effects on these risk factors.

Protein has also been blamed for osteoporosis, which is strange because the studies actually show that protein can help prevent osteoporosis. Overall, there is no evidence that a reasonably high protein intake has any adverse effects in healthy people trying to stay healthy.

Bottom Line: Protein does not have any negative effects on kidney function in healthy people and studies show that it leads to improved bone health.


Which are the best foods to provide protein?

why do we need protein

Many people typically turn to meat, poultry and dairy products to obtain protein. These food sources are considered to be of high value due to the protein in the food containing all the essential amino acids required to build muscle tissue.

  1. Lean Meats.
    Lean meats are high in protein, low in saturated fat and calories.
    Good examples of lean meats include chicken, turkey, some cuts of beef and seafood (salmon, mackerel, herring, lake trout, sardines and albacore tuna)
  2. Eggs.
    Egg protein is very high quality.The protein found in eggs includes all the essential amino acids and is easily absorbed (high bio availability. Eggs are also high in saturated fat so consider using some egg whites if you eat a lot of eggs. Organic eggs are an excellent source of omega 3 fatty acids which lower the risk of developing cardiovascular disease.
  3. Dairy.
    Milk, cottage cheese and yoghurt are great ways of increasing protein intake
  4. Non-Meat Foods
    Non-meat foods (vegetables, grains, legumes) offer protein without saturated fat. With the exception of soy, non-meat proteins are not complete on their own; they lack one or more of the essential amino acids. A balanced diet built around a wide variety of non-meat proteins allows you to ingest all the essential amino acids. In addition to protein, these foods are high in nutrients such as fibre, vitamins, minerals and antioxidants which improve health. Good sources of non-meat proteins include rice, beans, nuts, whole grains and legumes.


Protein rich foods.

Each of the following foods provides approximately 10 g of protein.
These foods have moderate to low fat contents and are rich in other nutrients.

  • 2 small eggs
  • 30 g hard cheese
  • 70 g cottage cheese
  • 250 ml milk
  • 35 g lean beef, lamb or pork (cooked weight)
  • 40 g lean chicken (cooked weight)
  • 50 g grilled fish
  • 50 g canned tuna or salmon
  • 200g yoghurt
  • 150g natural fromage frais
  • 4 slices (120 g) wholemeal rye bread
  • 400 g cooked rice
  • 150 g lentils or kidney beans
  • 200 g baked beans
  • 60 g nuts or seeds


  • 2 large eggs > 16g
  • 125g of grilled chicken breast > 25g
  • 125g 1% fat cottage cheese > 18g
  • 100g of lean minced beef >25g
  • 25g whole almonds >5g
  • 100ml milk > 4g
  • 100g Greek Yogurt >7g
  • Slice Rye Bread > 4g

So without counting protein found in legumes you have reached and passed the 100g protein goal


Are protein supplements useful? Generally, we can obtain all the protein we require from a good mixed diet.
Occasionally, a supplement is a practical and convenient way to consume sufficient amount.

Many protein supplements are very expensive due primarily to the amount of marketing that accompanies products and the processing required to extract the protein from cow’s milk. They tend to provide very large amounts of protein and little other nutrients.

If you are willing to use a supplement I suggest a natural organic whey such as Pink Sun, or a Rice Protein.

Please feel free to ask me about how to incorporate these into your diet.

I hope this has clarified the importance of protein
And why I continuously suggest you boost your diet with protein power.


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