FOOD – what is it?

Food – Photo by Leonie Elizabeth. 26 July 2020

What is Food?

Food is such an integral part of our daily lives, you would think there would be a short, simple and universally accepted description. Alas, this is not so and there are several and somewhat conflicting definitions. Today there are over 120,000 (1) foods available world-wide and up to 40,000 choices in Australian supermarkets (2). Food-types range from basic food commodities to extractions from foods to products with a multitude of ingredients. This is a brief outline of the various definitions of the different foods and food product types, and descriptions of what is classified as food and what isn’t.


“Food” can be simply described as substances (including drinks) that nourish us, vehicles for nutrients of carbohydrate, fat, protein, vitamins, minerals, and trace elements. Nutrition textbooks define food in this manner, as substances ‘derived from plants or animals that can be taken into the body to yield energy and nutrients for the maintenance of life and the growth and repair of tissues’ (3).

The three important elements therefore that define a food from a nutritional perspective are:
(1) it must contain at least one nutrient
(2) it must perform at least one function of keeping us alive or healthy, and
(3) it is derived from plants or animals – or in some cases fungi or insects.
It follows that no substance can be defined as ‘food’ unless it satisfies those three elements.

Food regulations governing supply and food safety, however, have a broader sweep and describe ‘food’ as ‘anything that is intended or offered for human consumption’ (4), which can include animals, plants, prepared or partly prepared; ingredients; additives; anything used in its preparation; anything coming in contact with that substance, such as processing aids; or chewing gum (5-7). In other words, anything edible.

Therefore, although from a supply perspective, ‘food’ can be any substance that we can consume (all the items on supermarket shelves), not everything we consume as food or within foods is actually ‘food’ (from a nutritional perspective) as some foods, and some substances added to food, provide no nutrients, do not contribute to the primary function of food, or are not derived from plants or animals.

Continue reading “FOOD – what is it?”

Potato Protein Power


“Potatoes” – Photo by Leonie Elizabeth 23 December 2017

If you have read one or many nutrition articles of recent years you would be forgiven for thinking that potatoes are nothing but carbohydrates with no other purpose as a food than converting to sugar, spiking blood glucose and creating havoc to our metabolic systems. Once a proud staple food, it has been attacked by dieters and professors alike, even relegated to the top tier (use sparingly) in an alternative Healthy Eating Pyramid.

You would also be forgiven for thinking of other foods, usually animal foods, as protein.

In food guides, foods are placed into various groups of similar nutrient value and these are usually fruit, vegetables, cereals, dairy and then a fifth group often named ‘protein‘ foods. Here ‘protein’ foods refer to meat, eggs, fish, poultry, legumes and nuts. The UK Eatwell Guide (1), although listing examples, refers to this group as ‘proteins’; the US Dietary Guidelines (2) refers to this group as ‘protein’ and ‘protein foods’; and the US Choose MyPlate as ‘protein’ (3). I note the Australian Dietary Guidelines (4) do not refer to this food group as ‘protein’ but rather lists the foods within the group ie: meat, poultry, fish, egg, tofu, nuts, seeds, legumes/beans. The Australian example aside, such messages of ‘protein’ as a food group from nutrition authorities in the UK and US, has a flow-down effect to health professionals and the public and this theme of ‘protein’ as a food group is common in the lay-press. One could mistakenly assume that those foods (meat, eggs, fish, poultry, legumes, nuts) are solely or predominantly protein; and that cereals, grains, tubers, potatoes, vegetables and dairy foods (which appear in different food groups) are thus low, inferior or poor quality sources of protein. Neither assumption is correct. Continue reading “Potato Protein Power”

Talking about fat …

Photo 1-11-18, 6 17 36 pm

In food and nutrition “fat” or “fats” have various meanings:

  • Fat is a food nutrient.
  • Fats is a food group.
  • Fat is a component in the blood.
  • Fat is a description of body size.
  • Fat is a body tissue.

Confusingly, some writers mix these terminologies up. Even more confusingly, these various meanings of fat can be described by different words and in various ways.

Continue reading “Talking about fat …”

Food. What’s in it?


Pear Ingredients (1-5). Photo by Leonie Elizabeth. January 2018


Food is comprised of many distinct chemical substances which can broadly be divided into nutritional and non-nutritional components.(6-8)

Nutritional components

Nutrients are chemical substances in the food we eat that interact within the body and are needed throughout the whole of life. There are six main types of nutrients in foods, divided into 2 main groups. Continue reading “Food. What’s in it?”

Good foods, bad foods


Photo 2-3-18, 12 28 11 pm
Bread, rice, pasta, oats, potatoes, wheat /oats cereal. Photo by Leonie Elizabeth 01 March 2018.


Good food, bad foods

When my eldest son was about seven years old, he came to me distressed about a school project on food. He had learned from his teacher that brightly coloured vegetables and fruit were good foods. He had also learned fatty snacks such as crisps, and confectionery were bad foods. His distress was that he didn’t know how to classify many of the foods our family were eating. He wanted to know whether we ate good or bad foods.

There was a background to his question. Continue reading “Good foods, bad foods”