Q What is the reason for beard or moustache not growing even at the age of 21
Beard and mustache usually start sprouting after the hormonal changes start in an individual. Normally, it start at the age of 14-16 yrs. But, if you are not having them until the age of 21, The commonest cause could be a hormonal deficiency. Other causes can be zinc deficiency, testosterone deficiency, congenital adrenal hyperplasia, failure to develop hair roots, etc. You will need to be investigated to find the exact cause in your case, you may visit an endocrinologist for this purpose. Do not equate presence of a moustache with manhood. If you are otherwise normal and/or other men in your family have scanty beard growth too; then probably there is nothing wrong with you.