What are natural ways to increase height at the age of 19?

Platform shoes: Unfortunately, the majority of people have ceased growing in height by 19 years old. Your doctor could obtain a screening x-ray to see if the growth plates in your long bones have closed. If so, only surgical manipulation will change nature.

Likely done growing: Most men are done with vertical growth by about 20..Some may stop a bit earlier and some later, but my guess would be around 20. Unfortunately, we continue to grow sideway persistently into oldage. Unfortunately there isn't any natural way to grow taller once the growth plates are sealed. Painful and expensive lengthening surgeries can be done, but why need to? Be healthy/happy. :-) good luck.