Hair Thickness, Texture and Hair Counts
The actual number of hair follicles on a human scalp varies between 90,000 and 140,000 and is mainly determined by genetic factors. The number you are born with is the most you will ever have as they cannot be added to later in life. Each hair follicle goes through three growth phases. 85%-90% of hair follicles are in the growth phase whereas the remaining 10%-15% are either in the transitional phase or in the resting phase - shrunk to about 1/6th of their original length, no longer growing and just waiting to be replaced by new budding hair. However, the thickness of your overall hair cover is not only determined by the total number of hair-producing follicles. The hair's individual thickness (diameter) can vary significantly, so that a person who has straight blond hair that is thin in diameter, even though they have a larger hair count, will create the impression of having less hair than somebody with curly, course hair of much bigger diameter, though fewer in number.
The diameter of human hair on the scalp varies between 0.04mm and 0.25mm. The thickest hair on a human body is a man's moustache, which is 0.3mm in diameter. The hair thickness is determined by the size of the hair follicles, whereas the size of the hair follicles is mainly determined by their number on the scalp. The larger the number of hair follicles the smaller they are. The hair's texture can vary from very straight Asian hair to extremely curly afro hair. The shape of the hair follicles determines the hair's curliness. It is obvious that curly hair gives the impression of the person having more hair. The hair's thickness, texture and hair counts, as well as its colour and the average number of hair follicles within a follicular unit, are among the chief determining factors of a person's suitability for hair transplantation and they eventually determine the cost of the surgery needed to achieve the desired result. Transplanting wavy, thick hair whose colour is close to that of the skin produces the best results and is also the most economical.