Glossary of Terms – Nutrition


Basal metabolic rate (BMR)

BMR is a measurement of the level of energy required to maintain the bodys vital life functions. Measured when the body is at complete rest. Energy source is referred to as Calories (imperial measurement) or Kilojoules (metric measurement). One calorie is equivalent to 4.19 kilojoules.

Body mass index (BMI)

BMI is a measure of a persons body size by calculating their weight in relation to their height. BMI = kg/m2

Body composition

Body composition refer to the bodies composition of organs, adipose tissue (body fat), lean tissue, water, bones etc.  When used within the body measurements, we are looking at the ratio of lean mass (total weight of organs, water, lean tissue, bones) vs adipose tissue.

Estimated Energy Requirements

This is calculated as a combination of age, bmr, activity levels etc to identify your estimated energy requirements dialy.  It is generally within 1-200kcals above or below the actual calculation. We use this figure as a baseline to estimate caloric requirements to achieve weight loss, weight gain or fat loss.  Important to remember, weight loss is not fat loss and vice versa.


Energy is the fuel we need from food to function and be active. Energy requirements vary depending on your age, body size and physical activity. It’s important to monitor your energy consumption as too much energy can lead to weight gain. Fat, protein and carbohydrates all provide energy (known as kilojoules or calories) in the foods we eat. Fats provide more energy per gram (9/g) than protein (4.19/g) or carbohydrates (4.19/g).


Metabolism refers to the chemical processes that occur in our body that turn what we eat into energy. This energy can then be used for all activity including walking, talking, thinking and breathing.



Nutrients are considered both macro and micro and are obtained from food the food we eat.  Different nutrients are responsible for different physiological processes in our bodies. Macro nutrients are carbohydrates, fats, proteins - macro meaning large with these nutrients being the main nutrients our bodies need to function and micro nutrients - meaning in small amounts with these nutrients being vitamins and minerals


Macronutrients are the key nutrients in the diet that provide us with energy. They are carbohydrate, protein and fat.


Micronutrients  refer to the nutrients we need in smaller amounts to sustain our health.  This measure is commonly used when working out our vitamin and mineral needs.


Protein is important for growth of body cells and makes up virtually every part of the body. Protein can be found in dried peas, soy and baked beans, peanut butter, nuts, eggs, cheese, lean meat, fish and wholegrains.


Carbohydrates are the bodies preferred energy source. Two main types of carbohydrates - Simple (which means it reaches our blood sugar quickly due to the lack of processing required by the body) and Complex (a slower release energy that helps keep blood sugar levels consistent as they take time to be processed and broken down by the body.) Good sources include rice, bread, cereal, legumes, fruits and vegetables which also provide important nutrients. Additional carbohydrate sources include refined sugars, which do provide instant energy but unfortunately don't offer the nutrients that the more complex sources of carbohydrates do.


Fats (or lipids) are an essential source of energy in the diet as they:

  • are a carrier for the fat soluble vitamins (A, D, E and K)
  • form part of cell membranes
  • provide a very concentrated source of energy
  • provide the starting ingredient for some hormones
  • provide essential fatty acids which our body cannot produce

However fat should be eaten sparingly as too much can lead to weight gain, heart disease and some cancers. The type of fat eaten is also important:

  • Polyunsaturated and monounsaturated fats - (good) can help reduce cholesterol. They are found in sunflower, olive, canola oils and margarines as well as many nuts, seeds and soy foods. Omega -3 is an important polyunsaturated fat found in fatty fish such as salmon and in the ancient wholegrain Salba.
  • Saturated and trans fats - ('bad') can raise cholesterol levels and therefore increase your risk of heart disease. Saturated fats are present in many foods and are generally found in higher amounts in animal-based products and are a required part of our diet in small amounts. Trans fats can be found in processed foods such as margarine and foods such as commercially baked biscuits, cakes and pastries. 


Alcohol serves a mention here as it is commonly referred to as the 4th Macro.  Alcohol has almost as much energy per gram as fats (7/g) but the body treats it differently. Alcohol is oxidized preferentially over other nutrients.  This means that, the foods we consume with alcohol sit within our system until such time as the alcohol itself is metabolised out of our system.  So what does that mean for that glass of wine or two (or three) we have each night?  In a simplistic way of explaining, it means that the energy from carbohydrates and fats are sent to adipose tissue to be used at a later date and the proteins don't do their job efficiently as the liver is metabolising the alcohol.  It is one of the reasons we feel so sluggish after a night out - the energy (7 cals/g) is being used and because it is not an efficient source of energy, it impacts on how we feel.


Minerals are important for the formation of bones, teeth, blood and connective tissues.  Minerals are obtained from the food we eat and play a role in many important functions within the body, including supporting healthy nerve function, muscle contractions etc.


Vitamins are molecules that are needed in small amounts by the body for health and growth, and they must be obtained by the diet daily. The exceptions to this rule are vitamin D, which is made in the skin when exposed to sunlight and vitamin K, which can be synthesised by gut bacteria in small amounts. Vitamins play an essential role in releasing energy from food and in speeding up many chemical reactions that occur in the body every second. They also play important roles in the formation of body components, such as blood and bone as well as being antioxidants.


Water is one of the nutrients that our body requires for health and it makes up 50-70% of our body weight. All cells in the body require it and adequate water intake helps prevent dehydration. We need 30-35mls per kilo of body weight as a minimum dialy to prevent dehydration.  However, if you are an active person you will require more. Signs that a person may be dehydrated, even slightly include: inability to concentrate, confusion, tiredness, moody, dark coloured urine or dried cracked lips. 


Amino acids

Amino acids are the building blocks of all proteins. There are 20 different amino acids that combine in different sequences to make all the proteins required for metabolism and growth. Our body can produce 12 of these amino acids naturally, but others need to come from the food we eat. 

Essential amino acids

Essential amino acids are the amino acids that the body cannot synthesise itself in sufficient quantities for physiological needs and must therefore be acquired from the diet. There are 8 essential amino acids required for adults and 9 for children.

Complementary proteins (Or Incomplete proteins)

Complementary proteins are the proteins supplied by different foods that combine together to supply all the essential amino acids. The proteins present in one food complement the proteins in another food to supply any essential amino acids that the other may be missing.

Complete proteins

Complete proteins are foods that contain all the essential amino acids in levels required by the body and do not require other foods to supply any.


Electrolytes are minerals which are needed to keep the body's balance of fluids at a healthy level and to maintain normal functions, such as heart rhythm, muscle contraction, and nerve impulse transmission. Electrolytes include potassium, sodium, calcium, and magnesium.


Fibre plays a key role in preventing constipation, cancer and heart disease. Wholegrain breads, cereals, legumes, rice, pasta, fruit and vegetables are good sources of fibre. There are a number of different types of dietary fibre. The three major types are soluble fibre, insoluble fibre and resistant starch. (Although it is not actually a fibre, resistant starch is now being recognised as a member of the ‘fibre family’ due to its similar effects on the body.)

  • Soluble fibre

Soluble fibre is beneficial to help lower blood cholesterol levels and, in people with diabetes, helps to control blood sugar. Soluble fibre is found in fruits, vegetables, dried peas, soybeans, lentils, oats, rice and barley.

  • Insoluble fibre

Because of its ‘bulking properties’, insoluble fibre helps keep us ‘regular’. Foods containing insoluble fibre include wholegrain and wholemeal wheat-based breads, cereals and pasta.Cellulose is an insoluble fibre that makes up the framework of plant cell walls

  • Resistent Starch

Resistant starch is a type of starch found in plant foods that escapes digestion in the small intestine. Resistant starch may provide similar benefits to other types of fibre, such as helping to prevent constipation. Foods containing resistant starch include firm bananas, roasted chickpeas, boiled long grain white rice, baked beans, cooked and cooled potato, as well as cornflakes.

​Food allergy

A food allergy is an abnormal reaction of the bodys immune system to a protein in food. When the body comes in contact with the food protein, substances are released which cause inflammation (redness and swelling) and the symptoms of an allergic reaction. The symptoms of a true food allergy may include: an itchy rash, swelling or burning around the mouth and throat, vomiting, stomach cramps, hives, diarrhoea, wheezing and eczema. Severe reactions may cause asthma and allergic shock (called anaphylaxis). The most common foods in Australia that are linked with allergic reactions are: eggs, cows milk and peanuts. Other foods include: fish, wheat and soy.

Food aversions

Food aversions are a strong desire to avoid certain foods. This is not a food allergy or intolerance but may come from an association to an unpleasant event in the past with a certain food.

Food intolerance

A food intolerance is an adverse reaction (that does not cause an immune response) of the body to compounds found in a variety of foods. Common symptoms are irritation of the stomach or bowels, hives, mouth ulcers, nausea, nasal congestion and diarrhoea. Food intolerances may also cause tiredness, weakness, headaches, irritability and muscle aches. Intolerance may occur to salicylates, amines and monosodium glutamate (MSG).


Gluten is a protein found in wheat, rye, barley, triticale and possibly oats (dependant on cross-contamination during processing). It is the gluten that gives dough its sticky cohesiveness which is important in manufacturing many products such as bread.

Glycaemic index

The Glycaemic Index (GI) classifies carbohydrates based on how they effect our blood sugar levels. Foods are rated between 0 and 100. They are classified as being low, moderate or high GI. The lower in GI a food is, the less likey it is to spike blood sugar levels due to the fact that they break down and release a lot slower into our systems than those foods with a higher GI.  Complex carbohydrates are mostly lower GI foods.

Glycaemic load

The glycemic load (GL) of food estimates how much the food eaten raises a person's blood sugars and is considered to be significant for those individuals managing blood sugar levels rather than weightloss. It is calculated by multiplying the weight of available carbohydrate in the food (in grams) by the food's glycemic index, and then dividing by 100.  


Glycogen is the store glucose within our bodies.  It is stored in the liver and around muscles and is used when required for energy 


Insulin is a hormone produced in the pancreas in response to increased blood glucose levels. Insulins primary role is to transport glucose from the bloodstream into the muscle and tissues.


Lactase is the enzyme produced in the small intestine that is required to breakdown lactose.


Lactose is the sugar found in milk. The body breaks it down to glucose and galactose.


Phytoestrogens are a type of plant chemical that have a similar structure to the hormone oestrogen, however they are not identical in their effects. Two major types of phytoestrogens are isoflavones and lignans. Phytoestrogens occur naturally in legumes, wholegrain cereals, nuts and seeds, and many vegetables and fruits

Plant sterols

Plant sterols (also known as phytosterols) are substances that can help lower your cholesterol. They are found naturally in very small amounts in a variety of plant foods such as grains, vegetables, fruit, legumes, nuts and seeds. Only small amounts can be obtained through our diets, so enriched foods are needed to help us achieve an effective intake of plant sterols that will lower high cholesterol.

When consumed, plant sterols reduce the absorption of cholesterol from your intestines into the body. This includes both the cholesterol you eat (called dietary cholesterol) and that made by your liver, which enters the intestines through bile.

Based on many clinical studies (over 120 studies), the effective dose of plant sterols from enriched foods has been identified as 2-3 grams per day. The evidence shows that the cholesterol lowering effect of plant sterols starts to plateau between 2 and 3 grams per day, and consuming in excess of this 3 grams per day doesn’t provides further benefits. Based on the evidence, heart health authorities globally, including the Australian Heart Foundation, British Heart Foundation and the European Society of Cardiology recommend people with high cholesterol eat 2-3 grams of plant sterols each day to lower elevated LDL cholesterol.