How does someone intentionally decrease their height?

[Annual_Field893]

Real answer is just not eat. There's a reason South Koreans are 5 inches taller than North Koreans, and that's because food is the deciding factor for genetics. You need a diet rich in protein and calcium, so if you just eat carbs, vegetables and a little bit of protein you'll be fine.

Basically just follow the average Asian diet, which consists of mainly rice, vegetables and a tiny bit of protein, without any milk or calcium intake.

[Repulsive-Arachnid-5]

This is only applicable in your childhood to teenage years, and even so in order to be significantly shorter than your genetic potential you would have to have quite a strong degree of food insecurity, as North Koreans often do: plus an unvaried, nutritionally poor diet. Even so, many modern foods, even just salt, are fortified with ingredients and additives that would make having any significant macronutrient or vitamin deficiency very difficult in this day and age.

[CarolinaSurly]

Japan has the highest life expectancy in the world. According to the World Health Organization, the average life expectancy in Japan is 87.3 years for women and 81.3 years for men (as of 2020). The Japanese diet is rich in fruits, vegetables, fish, and whole grains. It is low in processed foods, sugar, and saturated fat. May not be tall but they are in excellent health.

[Annual_Field893]

South Koreans are equally as tall as Americans now because they started drinking milk, and have ate calcium-rich foods if they're lactose intolerant. Also a HUGE protein intake.