SACE Stage 2 Nutrition key terms

A nutrient that the body needs in large amounts to supply energy and building material, namely carbohydrate, protein and fat. Each contributes differently to energy intake and body function.

A vitamin or mineral needed only in small quantities, yet essential for growth, metabolism and disease prevention. Deficiencies can cause serious health problems even though no energy is provided.

The metric unit used in Australia to express food energy. One kilojoule is a small unit, so food labels usually report thousands of kilojoules (kJ) per serve or per 100 grams.

The amount of energy in a given weight of food, usually kilojoules per 100 grams. Foods high in water and fibre are low in energy density; foods high in fat are typically high.

The energy the body uses at complete rest to maintain breathing, circulation, temperature and cell activity. It usually accounts for the largest share of a person's total daily energy expenditure.

The relationship between energy taken in from food and drink and energy used by the body. A sustained surplus leads to weight gain; a sustained deficit leads to weight loss.

A measure of how active a person is, used with basal metabolic rate to estimate total daily energy needs. It rises with the duration and intensity of movement.

A screening ratio of weight in kilograms to height in metres squared. It estimates weight status for populations but does not distinguish muscle from fat or show where fat is stored.

A body measurement taken around the narrowest part of the torso, used to estimate abdominal fat. Excess central fat raises the risk of type 2 diabetes and heart disease.

A macronutrient made of sugars and starches that is the body's preferred quick energy source. It is classified as simple (sugars) or complex (starch and fibre).

The parts of plant foods that resist digestion in the small intestine. Fibre adds bulk, supports bowel health, slows glucose absorption and increases feelings of fullness.

A ranking of carbohydrate foods by how quickly they raise blood glucose compared with a reference food. Low-GI foods release glucose slowly and are useful in managing diabetes.

A macronutrient built from amino acids, needed for growth, repair and enzyme production. It can also supply energy when carbohydrate and fat intake are insufficient.

One of nine amino acids the body cannot make in sufficient amounts, so they must come from food. All must be present together for protein synthesis to occur efficiently.

Two or more plant foods eaten together whose amino acid patterns combine to supply all essential amino acids. Examples include legumes with grains or nuts with seeds.

A measure of how efficiently a protein food supplies essential amino acids for body protein synthesis. Animal proteins generally score higher than most single plant proteins.

A concentrated energy macronutrient that carries fat-soluble vitamins, insulates the body and supplies essential fatty acids. Its type, saturated or unsaturated, affects health risk.

A type of fat in which carbon chains are fully saturated with hydrogen, making it solid at room temperature. High intake raises LDL cholesterol and cardiovascular disease risk.

A fat with one or more double bonds in its carbon chain, usually liquid at room temperature. Monounsaturated and polyunsaturated types are associated with lower cardiovascular risk than saturated fat.

A polyunsaturated fat the body cannot make efficiently, found in oily fish, walnuts and some seeds. It supports brain function and helps regulate inflammation and blood clotting.

A waxy substance made in the liver and obtained from animal foods, needed for cell membranes and hormones. High blood levels, especially LDL, increase heart disease risk.

The nutrient needed in the largest quantity, transporting substances, regulating temperature and supporting digestion. Needs rise with heat, exercise and high fibre or protein intake.

The state of having enough fluid in the body for normal function. Even mild dehydration reduces concentration and physical performance and can cause constipation or kidney strain.

Deliberately adding vitamins or minerals to a food to prevent deficiency or improve public health, such as iodine in salt or folate in bread flour. It differs from enrichment and from supplementation.

The proportion of a nutrient in food that is absorbed and used by the body. It depends on the food source, cooking, and interactions such as vitamin C aiding iron absorption.

A concentrated source of a nutrient taken in tablet, powder or liquid form to add to dietary intake. It is not a substitute for a varied diet and can be harmful in excess.

The highest daily intake of a nutrient that is unlikely to cause harm to most people. Intakes above it increase the risk of adverse effects, especially from fortified foods and supplements.

The daily amount of a nutrient considered adequate to meet the needs of nearly all healthy people in a population group. It is used for planning diets and interpreting food intakes.

The feeling of fullness that follows eating and suppresses further food intake. It is influenced by fibre, protein, food volume, energy density and eating speed.

A food or drink that is not needed for a healthy diet because it is high in saturated fat, added sugar, salt or alcohol and low in essential nutrients. It should be limited to small amounts.

Reliable access to enough safe, nutritious food that meets dietary needs and preferences. It depends on availability, affordability, and the ability to store and prepare food.

An area where affordable, nutritious food is difficult to buy because of distance to shops or poor transport. Residents may rely on small stores with limited fresh produce.

The information printed on packaging, including the nutrition information panel, ingredient list, allergen warnings and health claims. It helps consumers compare products and make informed choices.

A statement linking a food or nutrient to a health outcome, such as calcium and bone strength. Claims are regulated and must be supported by evidence, not used for marketing exaggeration.

The amount of food typically eaten in one sitting, set by the manufacturer on the label. It may differ from a standard portion, so energy and nutrient figures must be interpreted carefully.

A condition in which body cells respond poorly to insulin, so glucose stays in the blood. It is linked to excess abdominal fat, physical inactivity and diets high in refined carbohydrate.

A condition of excess body fat that impairs health, commonly screened by a body mass index of 30 or above. It raises the risk of type 2 diabetes, heart disease and joint problems.

Poor nutritional status caused by inadequate, excessive or unbalanced intake of nutrients. It includes undernutrition as well as overweight and micronutrient deficiencies.

An immune reaction to a protein in food that can cause hives, swelling or anaphylaxis, even in tiny amounts. It differs from intolerance and requires strict avoidance of the trigger food.

A non-immune reaction to a food, such as lactose causing bloating or diarrhoea. Symptoms depend on the amount eaten and do not involve anaphylaxis, so tiny traces are usually tolerated.