Formerly known as The Cambridge Diet, the plan was developed after eight years of research by the University of Cambridge and the West Middlesex and Addenbrookes Hospitals in the 1970s. The original diet book was published in 1985.
What does it involve?
A very low calorie diet of soups, bars and shakes is combined with minerals, vitamins and fatty acids to reduce the loss of nutrients typical of low calorie restriction. The plan has been revised from its original incarnation to include a flexible series of energy intake levels, which can be as low as 415 kcal per day.
How does it work?
The body is pushed into ketosis, a state in which the dieter's body breaks down fat for its energy rather than glucose.
-The meals are intended to combine all necessary food groups to satisfy a body's nutritional needs and to stop a person craving foods
-If you stick to it, you will loose weight, and fast, due to the body being pushed into ketosis
-You are given very specific instructions to follow, which is ideal for anyone with a busy lifestyle who doesn't have the time or inclination to cook healthy meals
-You are provided with your own counsellor, which is also a good motivator for some people
-Ketosis can lead to bad breath due to the build up of chemicals in a dieter's blood
-Nausea. Some people have more sensitive stomachs than others and may develop nausea the first time they consume the products
-Dizziness is often caused by the diuretic effect that accompanies low calorie diets
-Diarrhoea may result due to some people's systems not coping with the minerals in the products
-Leg cramps can be caused by changes in the electrolyte (salts) levels in your blood and muscle
-Feeling cold - this is almost certainly due to a reduced thermogenic response to a lower food intake. Large meals cause the body to generate a lot of body heat, while smaller ones produce less heat
-The most common serious side effect of very low calorie diets is gallstone formation. Research indicates that rapid weight loss may increase cholesterol levels in the gallbladder and decrease its ability to contract and expel bile