Thanks for the query.
Many people believe or claim that one can grow after the age of 21. Others believe that our growth stops at 21 while many opine that it is at some earlier or later age when actual growth recedes and finally stops. Actually, there is no fixed age when growth stops. Rather, it is a period or age span when our growth plates close resulting in gradual receding of growth and finally stopping altogether. This age varies between individuals and is presumably determined genetically.
Growth plates are bone joints located in our knees and wrists which facilitate growth. When we sleep, the body creates growth hormones through the Growth Plates which helps us grow. Generally around the age of 21, these growth plates gradually close and we no longer use the growth hormone as we used to do.
The best way to increase growth is to attempt to increase the growth hormone in the body by getting more sleep, hot showers and exercise. Maintaining a healthy lifestyle also helps.