The process of growing up is a natural way of life. Plants, animals, birds, human beings – all start growing up just after the conception. In the first nine months the foetus develops in the mother’s womb and keeps on growing after birth also. When a child is born, he is about 50 cms high. And in the next 20 years his height becomes more than triple. Man’s growth stops after the age of 20-22 years. Do you know how man grows up and why his growth stops after a certain age?
In its simplest sense, growing means adding living matter to the matter that is already present in the body. In fact, these are mainly proteins that help the body to grow. We get these proteins from meat, fish, eggs, seeds, grains, vegetables, fruits, milk and its products. During the process of digestion these proteins get converted into amino acids. These amino acids produce cells and tissues. Minerals like calcium, magnesium, phosphorus, sodium, potassium and iron are also helpful in the physical growth. Tissues, muscles and bones are produced by proteins and minerals. Broken cells and tissues are repaired by proteins.
Now the question arises: why do we stop growing up after a certain age? In fact, the endocrine glands which secrete hormones directly into the blood stream control our body-growth. These glands are the thyroid glands (in throat), pituitary gland (in brain), thymus gland (in thorax) and some sex-glands. The pituitary gland controls the growth of bones. When a child is born, his thymus gland is very large, but it starts shrinking after the age of 13-14 years. The body attains full maturity by the age of 20-22 years and after that the growth stops. The glands responsible for the physical growth become less active after this age. After 40 years of age the body starts contracting. It contracts by about one centimetre every ten years. This contraction is due to the drying up of the cartilages in our joint and spinal column.