METABOLISM
The primary function of our metabolism is simply to provide the right amount of fuel ( at the right time ) to keep our bodies alive and functioning . It accomplishes this through a complex series of chemical reactions whereby food is converted to the energy we need . When we eat , the food we swallow enters our digestive tract and is broken down by digestive enzymes . Carbohydrates are converted to glucose , fats to fatty acids and protein to amino acids . Once these nutrients are broken down , they are absorbed by the bloodstream and carried into the cells of the body . Our metabolism then works to either release these nutrients as energy , use them to build and repair lean tissue or store them for later use .
There are two basic metabolic processes — one is constructive and is responsible for building and storing energy for the body . The other is destructive , though in a positive sense , as it breaks down nutrient molecules to release energy . The constructive metabolic process is called anabolism , whereas the destructive process is called catabolism .
Anabolism : promotes the growth of new cells , the maintenance and repair of tissues , and the storage of energy — usually through body fat — for future use . Small nutrient molecules are converted into larger molecules of protein , carbohydrates and fat .
Catabolism : is responsible for immediately providing the body energy to use . Instead of building up , it breaks down the nutrient molecules to release energy .
These two processes do not occur simultaneously but are balanced by the body based on several factors .
Catabolism , in particular — though some attribute this to overall metabolism — has three components :
1 . Basal metabolism : sometimes called resting metabolism , this is the metabolism component responsible for keeping you alive by ensuring normal body functions . Even if you were bedridden the whole day , basal metabolism is still at work . Basal metabolism is metabolism ’ s main component , as 60 to 70 percent of the calories from the food you eat
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