How rare is really straight hair?

Truly straight hair is relatively uncommon globally, as various degrees of wave or curl are more prevalent in diverse populations. Straight hair results from a round hair follicle shape, allowing the hair to grow straight out of the scalp without curling. Genetic factors and ethnic background influence the rarity of completely straight hair.
East Asians, mainly Chinese and Japanese populations, are more likely to have naturally straight hair due to genetic predispositions. However, even within these populations, variations exist. In other ethnic groups, including African or Mediterranean descent, straight hair is less common, and wavy or curly textures are more typical.
While straight hair might be less common than wavy or curly textures, the variety of hair types contributes to the rich diversity observed in human populations, highlighting the beauty of natural differences in hair textures worldwide.