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Helpful information, on weight control.

July 31st, 2006

When food energy intake exceeds energy expenditure, fat cells (and to a lesser extent muscle and liver cells) throughout the body take in the energy and store it as fat. In its simplest conception, therefore, obesity is only made possible when the lifetime energy intake exceeds lifetime energy expenditure by more than it does for individuals of “normal weight”.

In all individuals, the excess energy utilized to generate fat reserves is minute relative to the total number of calories consumed. This means that very fine perturbations in the energy balance can lead to large fluctuations in weight over time. To illustrate, an obese 40 year old who carries 100 lb of adipose tissue has only consumed about 25 more calories per day than he has burned on average - or the equivalent of an apple every three days. In comparison a very lean 40-year-old who carries only 15 lb of body fat will have exceeded his daily energy expenditure by about four calories a day - the equivalent of an apple every 18 days.

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