Hello,height depends on average height of your parents... if your parents are short then nothing can be done...and at age 21 also its difficult...take nutritious food ,protein rich food like chicken ,fish , pulses ,egg ,milk ,butter. Do Stretching exercises in early morning like skipping, cycling, swimming helps you a lot...Exercise at least five times per week. By using exercises that help with gaining height, you will naturally increase the level of growth hormones in your body. Certain weight training exercises, high intensity sprints and bar hanging can help you achieve this. you must strengthen your abdominal and back muscles first to get the most out of your exercises

Please don't fall prey to false hopes by alternative medicine. Growth is normally impossible after your age. All the best

Hello. Long bones of our body generally gets fully developed and fused by age of 21 years. It's really very difficult to increase your height after that age, specially by 3-4 inches. Still you can try daily exercises like skipping, hanging from a height etc. They may help somewhat. But medicines are not going to help you, be it allopathic, ayurvedic, unani or homeopathic. Hope this helps.

Upto now I.e 2016 its not possible.