{"id":433926,"date":"2026-02-05T08:00:34","date_gmt":"2026-02-05T07:00:34","guid":{"rendered":"https:\/\/www.ma-grande-taille.com\/?p=433926"},"modified":"2026-02-04T11:40:17","modified_gmt":"2026-02-04T10:40:17","slug":"pourquoi-cheveux-plus-clairs-enfance-foncent-age","status":"publish","type":"post","link":"https:\/\/www.ma-grande-taille.com\/cs\/beaute\/coiffure\/proc-svetlejsi-vlasy-v-detstvi-s-vekem-tmavnou-proc-vlasy-v-detstvi-tmavnou-a-pote-s-vekem-zesvetlaji-433926","title":{"rendered":"Pro\u010d vlasy, kter\u00e9 byly v d\u011btstv\u00ed sv\u011btlej\u0161\u00ed, s v\u011bkem tmavnou?"},"content":{"rendered":"

Mo\u017en\u00e1 si pamatujete sv\u00e9 blond nebo sv\u011btle hn\u011bd\u00e9 vlasy z d\u011btstv\u00ed, kter\u00e9 jsou nyn\u00ed tmav\u0161\u00ed. Tato zm\u011bna je naprosto p\u0159irozen\u00e1 a st\u00e1v\u00e1 se mnoha lidem. Je v\u00fdsledkem fascinuj\u00edc\u00ed sm\u011bsi biologie, hormon\u016f a genetiky, kter\u00e1 doprov\u00e1z\u00ed va\u0161e t\u011blo po celou dobu jeho r\u016fstu.<\/p>\n

P\u0159i narozen\u00ed: pigmentace se st\u00e1le vyv\u00edj\u00ed<\/h2>\n

P\u0159i narozen\u00ed jsou vlasy \u010dasto sv\u011btlej\u0161\u00ed, ne\u017e budou v dosp\u011blosti, a to i v p\u0159\u00edpad\u011b, \u017ee va\u0161i rodi\u010de maj\u00ed tmav\u00e9 vlasy. To je zp\u016fsobeno<\/a> st\u00e1le nezralou aktivitou melanocyt\u016f, bun\u011bk zodpov\u011bdn\u00fdch za produkci melaninu, pigmentu, kter\u00fd barv\u00ed k\u016f\u017ei, o\u010di a vlasy.<\/p>\n

U kojenc\u016f tyto bu\u0148ky produkuj\u00ed prim\u00e1rn\u011b feomelanin, sv\u011btl\u00fd pigment se zlat\u00fdmi nebo m\u011bd\u011bn\u00fdmi odlesky, sp\u00ed\u0161e ne\u017e eumelanin, kter\u00fd je tmav\u0161\u00ed a intenzivn\u011bj\u0161\u00ed. Vlasov\u00e9 vl\u00e1kno je nav\u00edc st\u00e1le tenk\u00e9, sv\u011btl\u00e9 a ne p\u0159\u00edli\u0161 hust\u00e9, co\u017e omezuje mno\u017estv\u00ed pigmentu, kter\u00e9 m\u016f\u017ee pojmout. V\u00fdsledkem jsou vlasy, kter\u00e9 jsou \u010dasto m\u011bkk\u00e9, z\u00e1\u0159iv\u00e9 a sv\u011btlej\u0161\u00ed ne\u017e ty, kter\u00e9 budete m\u00edt pozd\u011bji v \u017eivot\u011b.<\/p>\n

D\u011btstv\u00ed a puberta: kdy hormony hraj\u00ed hlavn\u00ed roli<\/h2>\n

S r\u016fstem, a zejm\u00e9na s bl\u00ed\u017e\u00edc\u00ed se pubertou, proch\u00e1z\u00ed va\u0161e t\u011blo skute\u010dnou hormon\u00e1ln\u00ed revoluc\u00ed. Steroidn\u00ed hormony, zejm\u00e9na androgeny (p\u0159\u00edtomn\u00e9 v ka\u017ed\u00e9m \u010dlov\u011bku bez ohledu na pohlav\u00ed), stimuluj\u00ed aktivitu melanocyt\u016f ve vlasov\u00fdch folikulech.<\/p>\n

Tato aktivace vede ke zv\u00fd\u0161en\u00e9 produkci eumelaninu, kter\u00fd postupn\u011b ztmavuje, tlust\u0161\u00ed a siln\u011bj\u0161\u00ed vlasy. Z\u00e1rove\u0148 se siln\u011bji projevuj\u00ed ur\u010dit\u00e9 geny spojen\u00e9 s pigmentac\u00ed, jako nap\u0159\u00edklad MC1R, OCA2 a SLC45A2, kter\u00e9 postupn\u011b fixuj\u00ed barvu vlas\u016f v dosp\u011blosti. Takto se d\u011btsk\u00e9 blond vlasy mohou vyvinout v ka\u0161tanov\u00e9, hn\u011bd\u00e9 nebo dokonce syt\u011b \u010dern\u00e9. Tento proces se obvykle stabilizuje mezi 20. a 30. rokem v\u011bku.<\/p>\n

\u00dast\u0159edn\u00ed role genetiky<\/h2>\n

V t\u00e9to transformaci hraje hlavn\u00ed roli va\u0161e genetick\u00e1 v\u00fdbava. Pokud vlasy va\u0161ich rodi\u010d\u016f s v\u011bkem ztmavly, je velmi pravd\u011bpodobn\u00e9, \u017ee se jim vyrovn\u00e1te. Tento jev je obzvl\u00e1\u0161t\u011b b\u011b\u017en\u00fd u ur\u010dit\u00fdch populac\u00ed, zejm\u00e9na v severn\u00ed Evrop\u011b, kde se z mnoha blon\u010fat\u00fdch d\u011bt\u00ed v dosp\u011blosti stanou brunetky.<\/p>\n

Genetika v\u0161ak nen\u00ed jedin\u00fdm faktorem. Intenzitu a rychlost tmavnut\u00ed vlas\u016f mohou ovlivnit faktory prost\u0159ed\u00ed, jako je vystaven\u00ed slunci, strava (zejm\u00e9na p\u0159\u00edjem tyrosinu, aminokyseliny prekurzoru melaninu) a oxida\u010dn\u00ed stres. Naopak u n\u011bkter\u00fdch asijsk\u00fdch a africk\u00fdch populac\u00ed z\u016fst\u00e1v\u00e1 barva vlas\u016f v pr\u016fb\u011bhu \u010dasu stabiln\u011bj\u0161\u00ed.<\/p>\n

A pozd\u011bji\u2026 n\u011bkdy n\u00e1vrat ke sv\u011btlu<\/h2>\n

Je zaj\u00edmav\u00e9, \u017ee toto ztmavnut\u00ed nen\u00ed trval\u00e9. S v\u011bkem, obvykle po 40. nebo 50. roce \u017eivota, se melanocyty postupn\u011b vy\u010derp\u00e1vaj\u00ed v d\u016fsledku st\u00e1rnut\u00ed bun\u011bk a oxida\u010dn\u00edho po\u0161kozen\u00ed. Produkce melaninu kles\u00e1, co\u017e vede k v\u00fdskytu \u0161ediv\u00fdch nebo b\u00edl\u00fdch vlas\u016f. Jedn\u00e1 se o formu reverzn\u00edho zesv\u011btlen\u00ed, kter\u00e1 p\u0159edstavuje novou p\u0159irozenou f\u00e1zi ve v\u00fdvoji va\u0161ich vlas\u016f.<\/p>\n

Stru\u010dn\u011b \u0159e\u010deno, tmavnut\u00ed sv\u011btl\u00fdch vlas\u016f od d\u011btstv\u00ed do dosp\u011blosti nen\u00ed z\u00e1hadou, ale harmonick\u00fdm biologick\u00fdm procesem \u0159\u00edzen\u00fdm va\u0161imi hormony, geny a pigmentov\u00fdmi bu\u0148kami. Tato p\u0159irozen\u00e1 transformace ilustruje pozoruhodnou schopnost va\u0161eho t\u011bla vyv\u00edjet se, p\u0159izp\u016fsobovat se a v pr\u016fb\u011bhu \u010dasu se znovu objevovat.<\/p>\n","protected":false},"excerpt":{"rendered":"Mo\u017en\u00e1 si pamatujete sv\u00e9 blond nebo sv\u011btle hn\u011bd\u00e9 vlasy z d\u011btstv\u00ed, kter\u00e9 jsou nyn\u00ed tmav\u0161\u00ed. Tato zm\u011bna je...","protected":false},"author":8385,"featured_media":433927,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"disable_msn":false,"footnotes":""},"categories":[5719],"tags":[97833,97240],"class_list":["post-433926","post","type-post","status-publish","format-standard","has-post-thumbnail","category-coiffure","tag-actu","tag-cheveux"],"image":{"medium":["https:\/\/www.ma-grande-taille.com\/wp-content\/uploads\/2026\/02\/Vos-cheveux-etaient-plus-clairs-enfant-_-Voici-pourquoi-ils-foncent-avec-lage-200x113.jpg",200,113,true],"large":["https:\/\/www.ma-grande-taille.com\/wp-content\/uploads\/2026\/02\/Vos-cheveux-etaient-plus-clairs-enfant-_-Voici-pourquoi-ils-foncent-avec-lage-500x281.jpg",500,281,true]},"custom":{"td_video":"","featured_image":"https:\/\/www.ma-grande-taille.com\/wp-content\/uploads\/2026\/02\/Vos-cheveux-etaient-plus-clairs-enfant-_-Voici-pourquoi-ils-foncent-avec-lage.jpg","author":{"name":"Julia Perez","avatar":"https:\/\/www.ma-grande-taille.com\/wp-content\/uploads\/2026\/10\/cropped-julia_perez-96x96.jpg"},"categories":[{"term_id":5719,"name":"Vlasy","slug":"coiffure","term_group":0,"term_taxonomy_id":5887,"taxonomy":"category","description":"

Rubrika Vlasy magaz\u00ednu The Body Optimist p\u0159in\u00e1\u0161\u00ed n\u00e1pady na st\u0159ihy, barvy a \u00fa\u010desy a rady k p\u00e9\u010di o v\u0161echny typy vlas\u016f: jemn\u00e9, hust\u00e9, rovn\u00e9, kudrnat\u00e9, afro, barven\u00e9 i \u0161ediv\u00e9. Na\u0161e vod\u00edtko: vyber si to, co je ti bl\u00edzk\u00e9 a co ti usnadn\u00ed \u017eivot, bez pravidel podle v\u011bku nebo postavy.<\/p>\n

Co najde\u0161 v rubrice Vlasy<\/h2>\n