Nutrition Macronutrients – What are they and why are they important?


So you may have heard people talking about Macro’s. But what are they and why are they important?

Macronutrients are found in the food we eat alongside micronutrients (which we will cover in another post)

Firstly there are technically four macronutrients:

  • Protein 
  • Carbohydrates 
  • Fats
  • Alcohol

Since we don’t require alcohol to form a healthy balanced diet it is not usually spoken about as a “macro”.

All of these macros come at a caloric cost:

  • 1g Protein = 4 calories
  • 1g Carbs = 4 calories 
  • 1g Fat = 9 calories
  • 1g alcohol = 7 calories.

Macro nutrients can affect many of the processes in our body including:

  • Hormone function
  • Immune system health
  • Metabolic function (energy production)
  • Digestion & Absorption 
  • Cell structure & Function
  • Body composition


Proteins are organic molecules that are made up of Amino acids (these are considered the building blocks of life).  They are required in the body for various processes such as:

  • To give our body structure & strength. (Building Muscle, Skeletal & connective tissues)
  • Create enzymes (Enzymes are biological catalysts.  In simple terms they accelerate the chemical reactions that take place within the bodies cells)
  • Create hormones & a cell signalling molecules.

Protein can be found in most foods but those considered high in protein include:

  • Lean meats: Beef, wild game, pork
  • Poultry: Chicken, duck, turkey
  • Fish & Seafood
  • Dairy: cottage cheese, plain greek yoghurt
  • Eggs
  • Beans & Legumes
  • Protein powder: Whey, rice, pea


Recommendations from Precision Nutrition state that you should consume between 1.4g – 2.0g of protein / kg of bodyweight.  People involved in more strenuous activity such as strength training or have an active job will be on the higher end.

More protein does NOT equate to more muscle gain.  

The by product of protein metabolism is ammonia.  High levels of ammonia are toxic to the body so it is converted into urea.  Urea is then collected by the kidneys and released from the body.  Over time the excess protein puts extra strain on the kidneys.

We will teach you how to calculate your “macro breakdowns” in another post.


Carbohydrates are the sugars, starches & fibres that are found in our food.

Types of carbohydrates:

Monosaccharides – They only contain (mono) one sugar group. These are the simplest form of carbohydrates:

  • Glucose 
  • Fructose
  • Galactose

Oligosaccharides – These are short “chains” of monosaccharides.

  • Glucose + Glucose = Maltose
  • Glucose + Fructose = Sucrose
  • Glucose + Galactose = Lactose

Complex carbohydrates – Polysaccharides have many (poly) sugar groups. These are the most complex form of carbohydrates.

  • Starch & Dextrins
  • Glycogen 

These carbohydrates are used in the creation of ATP (energy).

Simple carbohydrates are readily available to be used as energy where as the more complex carbohydrates are required to be broken down into glucose to be used as energy.

Once broken down, the bodies blood sugar levels rise and the pancreas produces insulin (a hormone which regulates the amount of glucose in the blood).

Insulin allows our cells to absorb blood sugar to be used for energy & storage.  This then reduces our bodies blood sugar levels.

The poor metabolism of carbohydrates is a causing factor in the development of type 2 diabetes, which occurs when the body becomes resistant to the insulin response. This can occur with the over consumption of processed, refined sugars that are found in “junk food”.

As complex carbs are broken down slowly and are accompanied by fibre they slowly increase the bodies blood sugar and keep insulin levels stable. The “Glycemic Index” was created to rank carbohydrates on a scale of 1 – 100  based on how quickly they raise the bodies blood sugar after eating.  The lower the number the slower the rise in blood sugar.

Check out this link for a list of low to high GI foods.


According to the Australian Department of Health you should be looking at between 45-65% of your diet to come from carbohydrates, although this can vary.

For every 1g of carbs you consume your body will hold roughly 3g’s of water.

This is the reason some people think they are losing fat quickly when they start a low carb diet.  As they aren’t consuming as many carbs, they aren’t retaining as much water which can give the impression they are losing fat.


Fats have been given a bad name but are actually essential to our health.

Dietery fat has 6 major roles within the body:

  • It provides us with energy (it’s the most energy dense macronutrient with 9 calories per gram).
  • It helps to balance hormones, especially our sex hormones.
  • They help transfer certain vitamins and minerals such as vitamins A,D, E & K.
  • It forms our cell membranes.
  • It forms our brain and nervous system.
  • It gives us two fatty acids that we can’t create on our own:
  1. Omega-6 fatty acid 
  2. Omega-3 fatty acid

As with carbohydrates there are also different types of fats:

  • Polyunsaturated 
  • Monounsaturated
  • Saturated
  • Trans 

These are determined by their chemical structure.  Without getting too deep into the chemistry the more hydrogen bonds in the chain the more saturated the fat is.

It is often mistaken that saturated fats should be avoided but in reality they should just be balanced out with monounsaturated & Polyunsaturated fats.

Trans fats are the fats that the body has a hard time breaking down, these generally come from industrial fat processing.  This is great for commercial food production but not for our body.

Eating lots of trans fats can:

  • Lower our HDL levels – These are considered heart healthy cholesterol as they remove excess cholesterol from cells & arteries and transport back to the liver.
  • Increase our own cholesterol production. 
  • Compete with essential fats for transport to the cells. 
  • Create and worsen essential fatty acid deficiencies.

Over time, this can increase the risk of many chronic diseases.

Foods higher in Saturated fat include:

  • Coconut oil
  • Cream
  • Dark chocolate (70% + cacao)
  • Butter
  • Fatty beef, lamb & pork
  • Whole fat milk & cheese

Foods higher in monounsaturated fats include:

  • Almonds
  • Avocado
  • Brazil nuts
  • Cashews
  • Egg yolk
  • Hazelnuts
  • Peanuts
  • Pistachios
  • Sunflower oil
  • Chicken & duck fat

Foods higher in polyunsaturated fat include:

  • Chia seeds
  • Fish (fish oil)
  • Flaxseeds (flaxseed oil)
  • Pine nuts
  • Walknuts
  • Sesame seeds
  • Soybean oil
  • Sunflower seeds
  • Cod liver oil

Foods high in trans fat are generally all of your processed food or “junk food”

For a healthy diet when want to incorporate a balance of these macronutrients.




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