Macronutrients Explained
Nutrients are defined as substances which are needed for energy, growth, repair and general body functions.
Macronutrients are the nutrients that are required in a large amount to ensure essential body functions be maintained. There are 3 macronutrients – carbohydrates, proteins and fats.
Carbohydrates:
Generally, it is recommended that carbohydrates make up 45-65% of your total calories. Carbohydrates supply the body with glucose, which is the fuel we use first when exercising (glucose can also be made less efficiently from excess protein). However, the amount of carbohydrates is reduced within some diets such as keto or low carbohydrate diets – more about this topic in
What is a keto diet?
It’s important to note that not all of the carbohydrates found in foods are digestible – these carbohydrates are referred to as dietary fiber. Although fiber is not able to be used as an energy source, it has other important roles in the body. It has a role in weight loss as fiber helps us remain fuller for longer and therefore helps reduce feelings of hunger between meals. As well as this it helps regulate the function of the gut.
Carbohydrates contain 4 calories per gram.
Carbohydrates are either simple or complex – generally speaking we want to include complex carbohydrates into our diet over simple carbohydrates.
Simple carbohydrates are quick energy which enter your blood stream and are used up or are stored as fat. Typically, they have little to no nutritional value. Examples are sugars, soft drinks, lollies, chocolate and other sweet products.
Complex carbohydrates are more sustained sources of energy, as the energy takes longer to enter the blood stream. Examples are whole wheat breads, pastas and flours, brown and wild rice, corn, legumes (lentils, chickpeas etc.), sweet potatoes and grains such as quinoa.
Protein:
Proteins are broken down into amino acids; these amino can then act as building blocks to help repair and grow our body’s tissues, build muscle, make essential hormones and support immune function. When provided in excess to these requirements, protein acts as an energy source via the conversion to glucose. When consumed proteins are slowly digested and therefore will maintain feelings of for longer, making us feel fuller with less food.
Proteins contain 4 calories per gram.
The amino acids are classified as either essential or non-essential dependent on the livers ability to synthesize these – essential amino acids cannot be synthesized by the liver and therefore need to be provided by the diet.
Proteins are found in either plant or animal sources – animal protein contain all essential amino acids, while plant sources do not. However, all essential amino acids can be gained if a
variety
of plant sources are consumed.
Examples of plant proteins are:
- Nuts, seeds, beans, legumes and other grains (wheat, rice).
Examples of animal proteins are:
- Meat (poultry, fish, shellfish, red meat).
- Dairy (milk, yoghurt, cheese, eggs).
Protein shakes and protein supplements can also be used to supplement the diet to increase protein intake.
Individual protein requirements are influenced by an individual’s age, exercise level, body composition, health status. However, we recommend at least 1g of protein per kg of lean mass.
Excess protein will be converted to glucose via the biochemical pathway gluconeogenesis and therefore protein will need to be controlled when following diets such as keto, where glucose is limited.
Fat:
Generally, it is recommended that fats make up 20-35% of your total calories. Fats are essential for health and wellbeing. As well as supplying energy they are vital for absorbing fat soluble vitamins (A, D, E and K) and carotenoids and supply essential fatty acids.
Fats contain 9 calories per gram.
There are four main types of fat:
1. Saturated fats:
a). Should be limited to <10% of the diet.
b). Found in foods such as meat, butter and cream.
2. Polyunsaturated fats
a). Two types of polyunsaturated fats, both essential fatty acids - omega3 and
omega6.
b) Both omega3 and omega6 need to be consumed in balance at around 1 gram
of omega3 to every 5-10 grams of omega6.
*Typical western diets are overabundant in omega6s and lacking in
omega3s.
c). Omega6s are found in oils from nuts and seeds (sunflower oil, canola oil),
processed foods, baked goods and grains.
d). Omega3s are found in oily fish, chia seeds, linseeds, walnuts and pecans.
3. Monounsaturated fats
a). Found in olives, avocados, macadamia nuts and oils from these foods.
4. Trans fats
a) Should be limited/not included within the diet.
b) Created when polyunsaturated fats are damaged due to heat and processing.
c) Found in processed foods, takeaways, cakes, biscuits and foods with a long
shelf life.
Too little fat within one’s diet can begin cravings for sweet foods and therefore need to be included in the diet – however, within our meal plans you will see the inclusion of healthy (unsaturated fats!).