The 4 stages of metabolism
What have the scientists discovered? It is true that the metabolism slows down with age, but not quite in the way we thought. In general, we can recognise four metabolic phases: from 0 to 1 year of age; from 1 year to 20 years; from 20 to 60 years; and from 60 years onwards.The first metabolic “age”, up to the first year of life, is characterised by a very high energy demand: in this phase the metabolism travels twice as fast as that of an adult. In other words, infants consume 50% more calories than adults for the same activities.After the first year of life, however, the metabolism begins to slow down a little at a time – by about 3% every year until the age of 20. At that point, i.e. from age 20 to 60, the metabolism stabilises, and then gradually slows down by about 0.7% per year. Finally, from the age of 60 to 95, the metabolism drops by about 25%.
There are, of course, individual differences, but at population level the trend does not change, just as there are no differences in relation to gender or significant changes at pregnancy and menopause, contrary to what might have been expected.
Stem cells. Cellular activity is highest during early childhood and gradually decreases over time, to the point of compromising the proper functioning of organs and tissues.