The use of very low calorie diets in obesity / report of the Working Group on Very Low Calorie Diets, Committee on Medical Aspects of Food Policy.

  • Great Britain. Working Group on Very Low Calorie Diets.
Date:
1987
Catalogue details

Licence: Open Government Licence

Credit: The use of very low calorie diets in obesity / report of the Working Group on Very Low Calorie Diets, Committee on Medical Aspects of Food Policy. Source: Wellcome Collection.

    12/54 (page 2)
    self-selected, low energy diets, but has restricted its recommendations to products defined as commercially produced nutrient preparations providing less than about 600 kcal (2.5 MJ) per day, marketed for use as a total food substitute. 1.4 Meetings of the Working Group 1.4.1 The Working Group was appointed at the beginning of 1986 following an earlier recommendation of the Committee on Medical Aspects of Food Policy. It has met five times. 1.4.2 We wish to express our appreciation and thanks for expert assistance to the Secretariat. We are grateful to those who have prepared working papers and have made documents available, and to those who have attended our meetings to contribute information. Their names are recorded in Appendix B. 1.5 Perspectives 1.5.1 The deposition of fat under the skin and around internal organs is a normal storage function for humans and animals. Its purpose is to provide a store of energy for use when food is unavailable. Fat stores are laid down when food intake exceeds energy needs and are used up when food intake is inadequate to meet these needs. In many societies today food intakes rarely fall short of requirements and fat stores are laid down but never used up. Some people accumulate excessively large fat stores and they are liable to discomfort, distress and disease as a result!. However, the lesser degrees of overweight or ‘plumpness’, recognised as a Body Mass Index (BMI)* of 25 to 30, are associated with little or no increase in risk to health and life. 1.5.2 Fat stores can be reduced by calling on them to give up their energy. This will happen whenever more energy is expended than is consumed in food and drink. Therefore, excessive fat storage is reduced by consuming less food energy than the body needs; the energy deficit is met by drawing on the fat stores. Increasing the body’s energy expenditure will accelerate the loss of stored fat. However, whenever the body is in a state of energy deficit, weight will also be lost because of the reduction of some non-fat tissues, ie a reduction in the fat-free mass (FFM). The FFM is made up of tissues such as muscle, body organs and bone. The degree of this loss of FFM may increase disproportionately with the degree of energy deficit. 1.5.3. Restricting the intake of food energy can range from complete starvation at one extreme to a reduction which just causes steady weight loss at the other. When food intake is lowered, the body adapts by reducing its energy expenditure to some extent. In an average sedentary person three- quarters of total energy expenditure is accounted for by the energy costs of *The Body Mass Index (also known as Quetelets Index) is widely used as an indicator of weight for height and is defined as the weight in kg divided by the height in metres squared (BMI = W/H?). Recommended ‘normal’ ranges of BMI are 20 to 25 for men and women?.