Glossary of terms

Here you will find definitions of terms used in resources on the Foodsource website. You will also find these definitions on the right-hand side within chapters. If you have any suggestions for new glossary items, let us know here.

A (12) | B (4) | C (12) | D (2) | E (7) | F (6) | G (3) | H (1) | I (5) | L (3) | M (10) | N (3) | O (3) | P (5) | R (1) | S (9) | T (1) | U (1) | W (4) | Y (1) | Z (1)


Microalgae are microscopic algae typically found in freshwater and marine ecosystems

Micronutrient deficiencies

Micronutrient deficiencies result from a diet lacking the essential vitamins and minerals that humans require in small amounts for proper growth, development, and bodily functioning. These include iodine, calcium, iron, zinc, and vitamins A, B, and C, among others. Micronutrient deficiencies are the cause of a range of diseases affecting physical and mental development, and can increase susceptibility to infectious diseases.

Micronutrient deficiency

Not getting enough of one or more micronutrients. This can happen even if a person is getting sufficient energy from their diet.


Micronutrients are minerals (e.g. iron) and organic compounds (e.g. vitamin A) found in food, which the body requires in very small amounts to produce substances such as enzymes and hormones. They are essential for proper growth, development and bodily functioning. Essential micronutrients are those that cannot be synthesised by the body and so must be obtained through diet.

Multiple burden of malnutrition

The simultaneous presence of more than one form of malnutrition in an individual, household or population.

Non-communicable diseases

Non-communicable diseases are diseases which are not passed from person to person. They are often long lasting and generally progress slowly. Examples include cardiovascular diseases, cancer, chronic respiratory diseases and diabetes. Unhealthy diets are one of the major risk factors for non-communicable diseases.

Nudge approaches

Nudge approaches are the specific application of nudge theory, whereby the physical or informational environment in which decision making takes place is purposefully changed in order to affect behaviour. On example is using smaller plates to subtly limit overall food consumption in canteens.

Nudge theory

Nudge theory is a concept in behavioural science, economics and political science which tries to achieve non-forced compliance with desired behaviours (e.g. policies). It does this through the adjustment of messaging and the context in which decisions are made, in ways that have been found to predictably affect the motives, incentives, and decision making of individuals and groups of people.

Organic farming

is an approach to farming in which synthetic chemical insecticides and herbicides and inorganic fertilisers are entirely or largely avoided. Underpinning organic farming is the idea that farming should rely on ecological processes, biodiversity and cycles adapted to local conditions, rather than the use of inputs with adverse effects (e.g. agrochemicals such as pesticides and synthetic fertilisers). Certification bodies (e.g. the Soil Association in the United Kingdom) specify the practices, methods of pest control, soil amendments and so forth that are permissible if products are to achieve organic certification.


Excesses of energy or a particular nutrient. Overnutrition generally refers to excessive intake of energy, but it can sometimes be used to refer to excessive intake of one or more other dietary components such as specific macronutrients or micronutrients. Overnutrition in terms of energy often results in being overweight or obese.

Ozone layer depletion

A decline in the level of ozone gas (O3) present in the earth's stratosphere, owing to its breakdown into oxygen (O2). This breakdown can be affected by natural processes, but is known to have been accelerated by the release of man-made chemicals, such as refrigerant gases. The ozone layer acts to reduce the amount of light at ultra-violet wavelengths reaching the earth's surface; wavelengths that can have harmful impacts on humans, including skin cancer.

Photochemical smog

Photochemical smog is observed as a haze in the atmosphere, typically near to cities. It is created through the action of sunlight on pollutants (nitrogen oxides and volatile organic compounds) emitted by automobiles and other industrial sources, which creates other pollutants harmful to health, such as ozone.

Planetary boundaries concept

The planetary boundaries concept refers to the idea that humans are substantially altering natural systems, and that beyond a certain level of change this may become irreversible and self sustaining. The potential result is a planet with environmental conditions that differ substantially from those in which human civilisation developed and to which many species and ecosystems are adapted. Planetary boundaries have so far been proposed for climate change, biodiversity loss, biogeochemical cycles, ocean acidification, land use, freshwater, and ozone depletion.

Precision farming

is an agricultural management practice that aims to supply plants or animals with precisely the amounts of agricultural inputs (e.g. water, pesticides, and fertilisers) they need at a specific location and moment in time, thereby increasing efficiency by reducing the total inputs needed for agricultural production, and reducing environmental impacts. Precision farming uses different types of technologies to measure, observe, and act upon factors that are relevant to the growth of crops and livestock. These can range from big data, GPS, robotics, sensors, and drones, to low-tech measures such as using bottle caps for applying the right amounts of fertilisers to individual plants. Aiming to optimize crop or livestock production, precision techniques include measuring, modelling, and responding to (site-specific) data, including weather forecasts, soil properties, soil water content, pests, and weeds.

Price elasticity

Price elasticity refers to how much the demand for a good is affected by a change in its price. A good is said to be price inelastic if a change in price means that there is little change in demand. An example might be medication or addictive substances, like tobacco. A good is said to be price elastic if a change in price greatly changes the demand for the good.