Wiktionary(1.00 / 1 vote)Rate this definition: quantity(Noun) A fundamental, generic term used when referring to the measurement (count, amount) of a scalar, vector, number of items or to some other way of denominating the value of a collection or group of items. You have to choose between quantity and quality.
When the body is making and using ketones we say that the body is in a state of ketosis. Ketosis begins after about 48 hours (2 days) or water fast for women, or about 72 hours (3 days) of water fast for men.
How to Get Into Ketosis. To get into ketosis you need low levels of the fat-storing hormone insulin. The most important way to do that is to eat a strict low-carb diet, also called a ketogenic diet. On top of the necessary ketogenic diet there are many ways to increase ketosis further.