A human being cannot reduce his or her height, since this is natural development of the body. Trying to prevent height development or trying to reverse it may produce dangerous effects.
As a person ages, he or she may start noticing a natural height reduction. This is because as human beings age, they tend to lose various body tissues and things like bone content and fats. This loss begins when a person reaches the age of 40. The height loss is estimated at about 0.4 inches every 10 years, according to National Institutes of Health in the United States.