In general, humans have indeed been getting taller on average in the U.S. and in many European nations over the last few hundred years, but the overall amount of change has been fairly small (from a few centimeters to a dozen or so centimeters).

Will average height continue to increase?

In fact, over the last 150 years the average height of people in industrialized nations has increased approximately 10 centimeters (about four inches).

Does height increase after 21?

Summary: For most people, height will not increase after age 18 to 20 due to the closure of the growth plates in bones. Compression and decompression of the discs in your spine lead to small changes in height throughout the day.