When to use 頭の毛 and 髪


Not sure if this question's been asked before (I searched beforehand but
nothing came up, so), but I just came across this sentence : "今一番大切なのは頭の毛だ。",
and I'm not having any comprehension problems linked to vocabulary and such,
but I was always under the impression that to say "hair" (on one's head), it's
"髪" (kami) that a person should use ? When should "頭の毛" be privileged instead
of "髪", and doesn't "毛", when meaning hair, mostly designates body hair in
specific ?




The English word "hair" is translated as
[髪]{かみ}、髪の[毛]{け}、[毛髪]{もうはつ}、[頭髪]{とうはつ} in Japanese.

[頭]{あたま}の毛 isn't wrong but it is not common.

