Body Hair Basics

WHAT IS BODY HAIR?

First, let’s talk about the different types of hair.  There are two main types of hair before puberty – scalp hair (the hair that grows on our heads) and vellus hair (the very fine hair that grows all over the body and is often short, very light in color, and not necessarily noticeable).  During puberty, vellus hair can be triggered by androgens (testosterone, but especially DHT) to become “terminal hair” (also called “androgenic hair”).  Terminal or androgenic hair is what we would consider “body hair.”  Body hair is coarser and often a slightly different color than scalp or vellus hair.  When vellus hair is triggered by DHT it can start growing as thicker, coarser, terminal hair.  DHT continues to be produced throughout a man’s life and sometimes leads to more hair growth than is wanted.  In the following sections we’ll discuss where male body hair normally grows and even discuss what’s more common when it comes to hair distribution on different areas of the body.  We’ll also discuss options for men when it comes to unwanted or excessive body hair.

So what do we know about the distribution of hair in men?  The answer is actually not all that much.   This is an area that has not been studied that often.  In fact, prior to this book the last major study was an observational study back in the 1960s on only white and black men.  For this book we surveyed over 800 men from multiple racial groups around the world – Asian, African/black, European/white, Hispanic, Indian/Pakistani, Native American, and men of mixed racial background.  Although the survey also included a handful of Middle Eastern, Polynesian, Melanesian, and Inuit men, not enough men from these groups participated making it difficult to determine meaningful trends in body hair growth in these ethnic groups.

 

WHEN BODY HAIR BEGINS GROWING

Hair growth varies from the timing of the beginning of growth and how much grows where.  The variability in timing relates to when DHT is released during puberty and adulthood. 

 

At the onset of puberty hair usually appears first in the pubic area, just above the penis and then spreads from there.  The next body hair to appear is usually axillary/armpit hair.  Hair may appear in one armpit slightly before appearing in the other.  Perianal hair is often the next body hair to appear.  Perianal hair appears on the perineum (the area behind the scrotum) all the way up the crack of the buttocks to the anus.  Hair on the torso typically begins on the lower abdomen first, then hair starts arriving in other areas of the abdomen, chest, and potentially the back. 

Other body hair may come in more slowly and gradually.  For example, arm and leg hair are present in childhood and increase during puberty; however, continued hair growth thickness and consistency may continue well after puberty.  Most men will have hair growth on the upper arms and upper legs, while almost all men have hair growth on the lower arms and lower legs. 

 

However, body hair growth is not something that only occurs during puberty.  In fact, many men will continue to have hair spread to greater areas, especially on the torso (chest/abs/back), as they age – with some men not reaching the fullest extent of hair growth until they are in their 30s.  This is because DHT, the hormone that triggers most male body hair, continues to be produced throughout a man’s life. 

 

WHERE BODY HAIR GROWS

There is great variability from one man to the next when it comes to the amount of body hair.  Where and to what extent hair grows has to do with the sensitivity of hair follicles in certain skin areas.  These sensitivities to DHT vary from one man to the next.  For example, two men may have the same levels of androgens but one may have more sensitivity to DHT in his chest while another man has less sensitivity.  The first will grow hair extensively on his chest and the second will not.  Also, certain areas of skin tend to be more sensitive to androgens than others.  For example, the skin just around the nipples and on the sternum is often more sensitive to DHT than other parts of the chest.  This explains why men with only a little bit of chest hair usually have some growth around the nipples and breastbone, while those men with extensive chest hair usually have denser hair growth around the nipples and sternum comparted to other portions of their chest. 

With very few exceptions, all men will have pubic hair and nearly all adult men grow facial and armpit hair.  However, men vary not only in where they grow hair but how extensively body hair grows in that area.  The overall results of our surveys found the following incidence of hair growth in men:

Body Hair Table.jpg

BODY HAIR AND ETHNIC BACKGROUND

Body hair also varies by race.  In fact, men from eastern Asia and Native Americans tend to be the least hairy ethnic groups while Europeans tend to be among the most hairy.  For example, our survey found that while nearly 94% of European/white men grew chest hair only 71% of Asian men did.  When it comes to extensive hair growth, European/white men again topped the survey with 75% having hair that covered the majority of the chest, compared to Asian men at 48%, African/black men at 53%, Hispanic men at 56%, men from India/Pakistan at 63% and Native American men at 51%. 

 

GOING INTO DETAIL - THE NEXT SECTIONS

 

In the following sections we’ll talk about the variations that are common in body hair growth among men.  As we go through each body area, we will discuss patterns and trends that may be of some interest to some men – wondering how “normal” or how “unique” they are when it comes to body hair growth. 

These sections include:

At the end of most sections are detailed tables giving the incidence of hair patterns in men across different ethnic backgrounds.  

Images on this page from top to bottom include:

  1. Original Table Design