What does ‘lose’ mean?
The loss of weight is usually associated with an increase in energy expenditure.
This can be measured in energy balance (EBIT) – a measure of the amount of energy spent by a system over a given period.
If your EBIT falls below the amount you spend on food, you are considered overweight.
But the effect of weight loss is less clear cut, as EBIT is influenced by a number of other factors.
If you are overweight and lose weight on a regular basis, the body uses fat to store energy and is therefore less sensitive to weight loss.
However, if you lose weight by increasing your energy expenditure, the weight is regained.
This process is called ‘weight regain’ or weight loss maintenance.
This may explain why people who are overweight often lose weight more slowly than those who are not.
This is known as the ‘slight weight effect’.
In the US, about 25% of overweight adults lose weight over the course of a year.
In Britain, it is estimated that around half of overweight people lose weight.
There is also a trend towards weight gain in the middle age group, with older people becoming heavier.
This could be partly because the body needs to use more energy for the maintenance of its weight.
In this case, the amount lost may be less than the amount gained.
A third way to lose weight is to eat less.
This method involves a gradual reduction in the amount your body uses.
This means you are gaining weight, but the rate of weight gain is much slower.
Another way to maintain weight loss may be to increase your activity.
Exercise may be a way of helping you to lose fat, but it can also increase your energy demands.
You need to get in at least twice a week to increase the amount that you burn.
Exercise can also improve your overall health and prevent problems like heart disease and diabetes.
The effects of weight and exercise are likely to vary across people.
The American Society of Clinical Nutrition (ASCP) advises that individuals should be able to lose between 1.5 and 3.5 stone (11 and 15 kilograms) of body weight over a year, and a woman should lose 2.5 to 4 stone (6 and 11 kilograms) over a decade.