Junk food
Junk food is a common term used for any food that is perceived to be unhealthy and has low or poor nutritional value. The phrase was coined by Michael Jacobson, director of the Center for Science in the Public Interest, in 1972. Examples of junk food may include, but are not limited to hamburgers, pizza, candy, soda and salty foods like potato chips and french fries.
A diet rich in junk food is not conducive to maintaining a balanced diet, as suggested by various government and non-profit health organizations. The term has been used by many different groups over the years including opponents of fast food industries and environmentalists.
Junk food nevertheless remains popular because it is relatively cheap to manufacture, easy to purchase, is convenient to consume, and has a lot of flavor because of its typically high fat, sodium, or sugar content. Its nutritional value is typically very high in empty calories. Junk food also may contain numerous food additives, which are used to enhance flavor, adjust texture, alter color, and prevent spoilage. For this reason many junk foods are also convenient in that they have very long shelf lives and often do not require any kind of refrigeration.
Since junk food is high in fats, sugars, and certain toxic chemicals, it is the leading cause of obesity, dental cavities, increasing cases of Type 2 diabetes, heart diseases, etc. They are very low on proteins, vitamins and fibre. Once children start consuming junk foods their intake of high-protein-vitamins-roughage diet substantially decreases and intake of milk and healthy fruit juices is replaced by soft drinks. This can cause a deficiency of calcium, milk being a rich source of calcium, resulting in weakening of bones.
Some types of chips that are said to be "junk food" are actually beneficial because they may contain polyunsaturated and monounsaturated fats. However, since they are fats, the intake of these should still be low. These foods are almost always high in sodium, which may contribute in causing hypertension (high blood pressure) in certain people.