Definitions
In Andrew F. Smith's Encyclopedia of Junk Food and Fast Food, junk food is defined as "those commercial products, including candy, bakery goods, ice cream, salty snacks and soft drinks, which have little or no nutritional value but do have plenty of calories, salt, and fats. While not all fast foods are junk foods, many of them are. Fast foods are ready-to-eat foods served promptly after ordering. Some fast foods are high in calories and low in nutritional value, while other fast foods, such as salads, may be low in calories and high in nutritional value."[8]
Junk food provides empty calories, supplying little or none of the protein, vitamins, or minerals required for a nutritious diet.[18] Some foods, such as hamburgers, and tacos, can be considered either healthy or junk food, depending on their ingredients and preparation methods. The more highly processed items usually fall under the junk food category,[19] including breakfast cereals that are mostly sugar or high fructose corn syrup and white flour or milled corn.[4]
Junk food can be defined through nutrient profiling. The United Kingdom's Advertising Standards Authority, the self-regulatory agency for the UK ad industry, takes this approach. Foods are scored for "A" nutrients (energy, saturated fat, total sugar, and sodium) and "C" nutrients (fruit, vegetable, and nut content, fiber, and protein). The difference between A and C scores determines whether a food or beverage is categorized as HFSS (high in fat, salt and sugar; a term synonymous with junk food).[5][20] Defining junk food as highly processed or ultra-processed food mainly considers the level of processing rather than nutrient profiles.[21]
In Panic Nation: Unpicking the Myths We're Told About Food and Health, the junk food label is described as nutritionally meaningless: food is food, and if there is zero nutritional value, then it is not a food.[22] Co-editor Vincent Marks explains, "To label a food as 'junk' is just another way of saying, 'I disapprove of it.' There are bad diets – that is, bad mixtures and quantities of food – but there are no 'bad foods' except those that have become bad through contamination or deterioration."[23]
