|MadSci Network: Biochemistry|
Hi Sasha, You have posed a very interesting question, and as you surmise you don't need to eat a pound of food to gain a pound in weight. Serveral things to remember include; (1) water is a major constituent of most foods and as such doesn't contribute to weight gain, but is necessary for normal body metabolic functions; (2) there are other constituents in foods that are not or only parially metabolized -- dietary fiber for example; (3) a significant amount of the caloric content of food is used to maintain normal body functions, and in the cases of infants, children and teenagers is used to support growth and devlopment; (4) the amount of exercise you do will also influence if you are taking in excess calories that will go toward weight gain. Exercise burns calories that could go toward weight gain. In simple terms if you balance the calories you consume against the calories you are using for the above functions, your weight should remain unchanged. I hope this helps to answer your question. Sincerely, Al Bushway Professor of Food Science
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