{"id":2094,"date":"2017-12-21T14:09:55","date_gmt":"2017-12-21T11:09:55","guid":{"rendered":"https:\/\/coskumutlu.com\/?p=2094"},"modified":"2017-12-21T14:09:55","modified_gmt":"2017-12-21T11:09:55","slug":"a-vitamini-hakkinda-bilmeniz-gerekenler","status":"publish","type":"post","link":"https:\/\/www.coskumutlu.com\/blog\/a-vitamini-hakkinda-bilmeniz-gerekenler\/","title":{"rendered":"A Vitamini Hakk\u0131nda Bilinmesi Gereken Her \u015eey"},"content":{"rendered":"<h1><span class=\"ez-toc-section\" id=\"A_VITAMINI_NEDIR\"><\/span><strong>A V\u0130TAM\u0130N\u0130 NED\u0130R?<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h1><div id=\"ez-toc-container\" class=\"ez-toc-v2_0_69_1 counter-hierarchy ez-toc-counter ez-toc-grey ez-toc-container-direction\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">\u0130\u00e7indekiler<\/p>\n<label for=\"ez-toc-cssicon-toggle-item-69ef88b7513cb\" class=\"ez-toc-cssicon-toggle-label\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/label><input type=\"checkbox\"  id=\"ez-toc-cssicon-toggle-item-69ef88b7513cb\"  aria-label=\"Toggle\" \/><nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><li class='ez-toc-page-1 ez-toc-heading-level-1'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/www.coskumutlu.com\/blog\/a-vitamini-hakkinda-bilmeniz-gerekenler\/#A_VITAMINI_NEDIR\" title=\"A V\u0130TAM\u0130N\u0130 NED\u0130R?\">A V\u0130TAM\u0130N\u0130 NED\u0130R?<\/a><ul class='ez-toc-list-level-2' ><li class='ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/www.coskumutlu.com\/blog\/a-vitamini-hakkinda-bilmeniz-gerekenler\/#A_Vitamini_Alimi\" title=\"A Vitamini Al\u0131m\u0131\">A Vitamini Al\u0131m\u0131<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/www.coskumutlu.com\/blog\/a-vitamini-hakkinda-bilmeniz-gerekenler\/#A_Vitamini_Nelerde_Var\" title=\"A Vitamini Nelerde Var?\">A Vitamini Nelerde Var?<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/www.coskumutlu.com\/blog\/a-vitamini-hakkinda-bilmeniz-gerekenler\/#A_Vitamini_Iceren_Besinler\" title=\"A Vitamini \u0130\u00e7eren Besinler\">A Vitamini \u0130\u00e7eren Besinler<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/www.coskumutlu.com\/blog\/a-vitamini-hakkinda-bilmeniz-gerekenler\/#A_Vitamini_Takviyesi\" title=\"A Vitamini Takviyesi\">A Vitamini Takviyesi<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/www.coskumutlu.com\/blog\/a-vitamini-hakkinda-bilmeniz-gerekenler\/#A_Vitamini_Eksikligi\" title=\"A Vitamini Eksikli\u011fi\">A Vitamini Eksikli\u011fi<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/www.coskumutlu.com\/blog\/a-vitamini-hakkinda-bilmeniz-gerekenler\/#A_Vitamini_Eksikligi_Riski_Tasiyan_Bireyler\" title=\"A Vitamini Eksikli\u011fi Riski Ta\u015f\u0131yan Bireyler\">A Vitamini Eksikli\u011fi Riski Ta\u015f\u0131yan Bireyler<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/www.coskumutlu.com\/blog\/a-vitamini-hakkinda-bilmeniz-gerekenler\/#Premature_Bebekler\" title=\"Premat\u00fcre Bebekler\">Premat\u00fcre Bebekler<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-9\" href=\"https:\/\/www.coskumutlu.com\/blog\/a-vitamini-hakkinda-bilmeniz-gerekenler\/#Gelismekte_Olan_Ulkelerdeki_Hamile_ve_Emziren_Kadinlar\" title=\"Geli\u015fmekte Olan \u00dclkelerdeki Hamile ve Emziren Kad\u0131nlar\">Geli\u015fmekte Olan \u00dclkelerdeki Hamile ve Emziren Kad\u0131nlar<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-10\" href=\"https:\/\/www.coskumutlu.com\/blog\/a-vitamini-hakkinda-bilmeniz-gerekenler\/#Kistik_Fibrozis_Olan_Bireyler\" title=\"Kistik Fibrozis Olan Bireyler\">Kistik Fibrozis Olan Bireyler<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-11\" href=\"https:\/\/www.coskumutlu.com\/blog\/a-vitamini-hakkinda-bilmeniz-gerekenler\/#A_Vitamini_ve_Genel_Saglik\" title=\"A Vitamini ve Genel Sa\u011fl\u0131k\">A Vitamini ve Genel Sa\u011fl\u0131k<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-12\" href=\"https:\/\/www.coskumutlu.com\/blog\/a-vitamini-hakkinda-bilmeniz-gerekenler\/#Kanser\" title=\"Kanser\">Kanser<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-13\" href=\"https:\/\/www.coskumutlu.com\/blog\/a-vitamini-hakkinda-bilmeniz-gerekenler\/#Yaslanmaya_Bagli_Makuler_Dejenerasyon\" title=\"Ya\u015flanmaya Ba\u011fl\u0131 Mak\u00fcler Dejenerasyon\">Ya\u015flanmaya Ba\u011fl\u0131 Mak\u00fcler Dejenerasyon<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-14\" href=\"https:\/\/www.coskumutlu.com\/blog\/a-vitamini-hakkinda-bilmeniz-gerekenler\/#Kizamik\" title=\"K\u0131zam\u0131k\">K\u0131zam\u0131k<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-15\" href=\"https:\/\/www.coskumutlu.com\/blog\/a-vitamini-hakkinda-bilmeniz-gerekenler\/#A_Vitamini_Fazlaligi_ve_Zehirlenmesi\" title=\"A Vitamini Fazlal\u0131\u011f\u0131 ve Zehirlenmesi\">A Vitamini Fazlal\u0131\u011f\u0131 ve Zehirlenmesi<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-16\" href=\"https:\/\/www.coskumutlu.com\/blog\/a-vitamini-hakkinda-bilmeniz-gerekenler\/#Tolere_Edilebilir_A_Vitamini_Ust_Limitleri\" title=\"Tolere Edilebilir A Vitamini \u00dcst Limitleri\">Tolere Edilebilir A Vitamini \u00dcst Limitleri<\/a><\/li><\/ul><\/li><\/ul><\/nav><\/div>\n\n<p>A vitamini ya\u011fda \u00e7\u00f6z\u00fcnen retinol, retinal ve retinil esterler gibi bir grup retinoide verilen isimdir. Retinoid nedir sorusuna verilebilecek en iyi cevap, retinoik asit k\u00f6kenli bile\u015fikler olduklar\u0131d\u0131r. \u00d6zellikle bir\u00e7ok kozmetik \u00fcr\u00fcnde bulunan bir bile\u015fik olan retinol nedir sorusunun cevab\u0131 ise, retinol\u00fcn de bir t\u00fcr retinoid olmas\u0131d\u0131r. Peki ya A vitamini faydalar\u0131 nelerdir? Bu vitamin, ba\u011f\u0131\u015f\u0131kl\u0131k sisteminde, g\u00f6rme mekanizmas\u0131nda ve h\u00fccreler aras\u0131 ileti\u015fimde rol oynamaktad\u0131r. G\u00f6zdeki retinal resept\u00f6rlerde bulunan ve \u0131\u015f\u0131\u011f\u0131 emmekle g\u00f6revli olan rodosphin proteinin de i\u00e7eri\u011finde bulunmaktad\u0131r. Bu y\u00fczden bu vitamin g\u00f6rme duyusu a\u00e7\u0131s\u0131ndan kritik bir besin \u00f6\u011fesidir ve zaman zaman g\u00f6z vitamini olarak da an\u0131l\u0131r. Ayn\u0131 zamanda h\u00fccre b\u00fcy\u00fcmesi ve de\u011fi\u015fimlerinde \u00f6nemli rol oynamaktad\u0131r. A vitamini g\u00f6revleri basit\u00e7e bu \u015fekilde s\u0131ralanabilir.<\/p>\n<p>Bu mikro besin \u00f6\u011fesi, insanlar\u0131n diyetlerinde iki t\u00fcrde bulunmaktad\u0131r; \u00f6nceden olu\u015fmu\u015f form (retinol ve retinol\u00fcn esterlenmi\u015f hali olan retinil ester.) ve provitamin A karotenoidleri (Provitamin nedir? Provitaminler, v\u00fccutta A vitamine d\u00f6n\u00fc\u015ft\u00fcr\u00fclen \u00f6nc\u00fcl bile\u015fiklerdir.).<\/p>\n<p>\u00d6nceden olu\u015fmu\u015f formu, s\u00fct \u00fcr\u00fcnleri, bal\u0131k ve \u00f6zellikle karaci\u011fer olacak \u015fekilde k\u0131rm\u0131z\u0131 et gibi hayvansal besinlerde bulunmaktad\u0131r. Kar\u015f\u0131m\u0131za farkl\u0131 isimlerle \u00e7\u0131kan bu vitaminin bir ba\u015fka ad\u0131 da beta karotendir. Peki beta karoten nedir? V\u00fccudun daha sonradan d\u00f6n\u00fc\u015ft\u00fcrd\u00fc\u011f\u00fc, en bilinen provitamin A t\u00fcrlerinden biri de bitkisel besinlerden elde edilen beta karotendir. Vitamin olarak v\u00fccutta g\u00f6revlerini yerine getirebilmek i\u00e7in provitaminlerin aktif hale getirilmesi gerekmektedir. Besinlerde bulunan di\u011fer karotenoidler ise likopen, lutein ve zeaksantindir.<\/p>\n<p>Bu vitamininin \u00e7o\u011fu v\u00fccutta renitil esterler \u015feklinde karaci\u011ferde depolanmaktad\u0131r.<\/p>\n<p>Plazmadaki seviyelerin saptanmas\u0131 i\u00e7in retinol ve karetonoid konsantrasyonuna bak\u0131l\u0131r. Fakat karaci\u011ferdeki depolar neredeyse tamamen bo\u015falmadan plazmada bu bile\u015fikler d\u00fc\u015f\u00fc\u015f g\u00f6stermeyece\u011finden, \u00e7\u0131kan sonu\u00e7lar yan\u0131lt\u0131c\u0131 olabilmektedir. Plazma retinol seviyelerinde %20\u2019ye yak\u0131n bir art\u0131\u015f olmas\u0131 yetersiz al\u0131m ger\u00e7ekle\u015ftirildi\u011fini g\u00f6stermektedir.<\/p>\n<p>0.7 mikromol\/L\u2019den daha az veya 20 mikrogram\/dl\u2019den daha az plazma A vitamini seviyesi, v\u00fccutta yetersiz A vitamini oldu\u011funun g\u00f6stergesidir.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"A_Vitamini_Alimi\"><\/span><strong>A Vitamini Al\u0131m\u0131<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>G\u00fcnl\u00fck takviye, retinol aktivitesi e\u015fde\u011ferleri (RAE) olarak mikrogram \u015feklinde belirtilir. Bu y\u00f6ntem provitamin A ve retinol bioaktiflerinin ayr\u0131m\u0131n\u0131n yap\u0131lmas\u0131 i\u00e7in kullan\u0131lmaktad\u0131r. 1 mikrogram retinol, 12 mikrogram beta karotene, 24 mikrogram alfa karotene veya beta kriptosantine e\u015fittir. Diyetle al\u0131nan 2 mikrogram beta karoteni v\u00fccut 1 mikrogram retinole d\u00f6n\u00fc\u015ft\u00fcrmektedir.<\/p>\n<p>G\u00fcn\u00fcm\u00fczde A vitamini miktar\u0131n\u0131n belirtilmesi i\u00e7in IU (international units) y\u00f6ntemi kullan\u0131lmad\u0131r. 1 IU retinol, 0.3 mikrogram RAE\u2019ye e\u015fittir.<\/p>\n<p><strong>Ya\u015f Gruplar\u0131na G\u00f6re G\u00fcnl\u00fck A Vitamini \u0130htiyac\u0131 (RDA) (FNB Verileri)<\/strong><\/p>\n<table>\n<tbody>\n<tr>\n<td width=\"80\"><strong>Ya\u015f<\/strong><\/td>\n<td width=\"80\"><strong>Erkek<\/strong><\/td>\n<td width=\"80\"><strong>Kad\u0131n<\/strong><\/td>\n<td width=\"80\"><strong>Hamilelik<\/strong><\/td>\n<td width=\"91\"><strong>Emziklilik<\/strong><\/td>\n<\/tr>\n<tr>\n<td width=\"80\">0\u20136 ay<\/td>\n<td width=\"80\">400 mcg RAE<\/td>\n<td width=\"80\">400 mcg RAE<\/td>\n<td width=\"80\"><\/td>\n<td width=\"91\"><\/td>\n<\/tr>\n<tr>\n<td width=\"80\">7\u201312 ay<\/td>\n<td width=\"80\">500 mcg RAE<\/td>\n<td width=\"80\">500 mcg RAE<\/td>\n<td width=\"80\"><\/td>\n<td width=\"91\"><\/td>\n<\/tr>\n<tr>\n<td width=\"80\">1\u20133 ya\u015f<\/td>\n<td width=\"80\">300 mcg RAE<\/td>\n<td width=\"80\">300 mcg RAE<\/td>\n<td width=\"80\"><\/td>\n<td width=\"91\"><\/td>\n<\/tr>\n<tr>\n<td width=\"80\">4\u20138 ya\u015f<\/td>\n<td width=\"80\">400 mcg RAE<\/td>\n<td width=\"80\">400 mcg RAE<\/td>\n<td width=\"80\"><\/td>\n<td width=\"91\"><\/td>\n<\/tr>\n<tr>\n<td width=\"80\">9\u201313 ya\u015f<\/td>\n<td width=\"80\">600 mcg RAE<\/td>\n<td width=\"80\">600 mcg RAE<\/td>\n<td width=\"80\"><\/td>\n<td width=\"91\"><\/td>\n<\/tr>\n<tr>\n<td width=\"80\">14\u201318 ya\u015f<\/td>\n<td width=\"80\">900 mcg RAE<\/td>\n<td width=\"80\">700 mcg RAE<\/td>\n<td width=\"80\">750 mcg RAE<\/td>\n<td width=\"91\">1,200 mcg RAE<\/td>\n<\/tr>\n<tr>\n<td width=\"80\">19\u201350 ya\u015f<\/td>\n<td width=\"80\">900 mcg RAE<\/td>\n<td width=\"80\">700 mcg RAE<\/td>\n<td width=\"80\">770 mcg RAE<\/td>\n<td width=\"91\">1,300 mcg RAE<\/td>\n<\/tr>\n<tr>\n<td width=\"80\">51+ ya\u015f<\/td>\n<td width=\"80\">900 mcg RAE<\/td>\n<td width=\"80\">700 mcg RAE<\/td>\n<td width=\"80\"><\/td>\n<td width=\"91\"><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h2><span class=\"ez-toc-section\" id=\"A_Vitamini_Nelerde_Var\"><\/span><strong>A Vitamini Nelerde Var?<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Sa\u011fl\u0131k i\u00e7in bir\u00e7ok faydas\u0131 olan A vitamini nelerde bulunur?<\/p>\n<h3><span class=\"ez-toc-section\" id=\"A_Vitamini_Iceren_Besinler\"><\/span><strong><em>A Vitamini \u0130\u00e7eren Besinler<\/em><\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>A vitamini hangi besinlerde var sorusu i\u00e7in verilebilecek cevap \u015fu \u015fekildedir; \u00f6nceden olu\u015fmu\u015f formu en fazla karaci\u011fer ve bal\u0131k ya\u011flar\u0131nda bulunmaktad\u0131r. Di\u011fer bu tip \u00a0kaynaklar\u0131 ise ayn\u0131 zamanda provitamin A da i\u00e7eren s\u00fct ve yumurtad\u0131r. Bir\u00e7ok diyette provitamin A ye\u015fil yaprakl\u0131 sebzelerden, turuncu ve sar\u0131 sebzelerden, domates \u00fcr\u00fcnlerinden, meyvelerden ve bitkisel ya\u011flardan gelmektedir. \u00d6nceden olu\u015fmu\u015f formu i\u00e7in en iyi kaynaklar karaci\u011fer ve bal\u0131kken, provitamin A i\u00e7in en iyi kaynaklar havu\u00e7, brokoli ve kabakt\u0131r. Miktar\u0131 y\u00fcksek olmasa da farkl\u0131 A vitamini olan besinler de bulunmaktad\u0131r.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"A_Vitamini_Takviyesi\"><\/span><strong><em>A Vitamini Takviyesi<\/em><\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Bu vitamin, kar\u0131\u015f\u0131k vitaminlerin i\u00e7inde veya tek ba\u015f\u0131na takviye olarak piyasada bulunmaktad\u0131r. Ayr\u0131ca, A vitamini ampul \u015feklinde de kar\u015f\u0131m\u0131za \u00e7\u0131kmaktad\u0131r. Genellikle vitaminlerin i\u00e7inde bulundu\u011fu format retinil asetat veya retinil palmitatt\u0131r. Bir\u00e7ok multivitamin 2,500-10,000 IU kadar i\u00e7ermektedir. \u00c7o\u011funlukla bu miktar hem retinol hem de beta karotenden olu\u015fmaktad\u0131r. Pop\u00fclasyonun yakla\u015f\u0131k %28-%37\u2019si bu vitamini i\u00e7eren takviyeler kullanmaktad\u0131r. Ya\u015f\u0131 71\u2019i a\u015fan yeti\u015fkinler ve 9 ya\u015f\u0131ndan daha gen\u00e7 olan \u00e7ocuklar bu tip takviyeleri almaya daha e\u011filimli olan bireylerdir.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"A_Vitamini_Eksikligi\"><\/span><strong>A Vitamini Eksikli\u011fi<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>D\u00fcnya Sa\u011fl\u0131k \u00d6rg\u00fct\u00fc verilerine g\u00f6re 190 milyon okul \u00f6ncesi \u00e7a\u011f\u0131ndaki \u00e7ocuk ve 19.1 milyon hamile kad\u0131n 0.70 mikromol\/L\u2019den az serum retinol konsantrasyonuna sahiptir.<\/p>\n<p>Geli\u015fmekte olan \u00fclkelerde A vitamini eksikli\u011fi ilk anne s\u00fct\u00fc olan kolostrumda yeterli miktarda bulunmamas\u0131yla birlikte bebeklik \u00e7a\u011f\u0131nda ba\u015flar. Ya\u015f\u0131 daha b\u00fcy\u00fck \u00e7ocuklarda ise ishal en b\u00fcy\u00fck eksiklik nedenlerinden biridir. K\u00fc\u00e7\u00fck \u00e7ocuklarda ve hamile kad\u0131nlarda eksikli\u011fin en s\u0131k g\u00f6r\u00fclen sonucu xeroftalmia ad\u0131 verilen bir g\u00f6z hastal\u0131\u011f\u0131d\u0131r. Bu hastal\u0131\u011f\u0131n ilk belirtilerinden biri gece k\u00f6rl\u00fc\u011f\u00fc veya az \u0131\u015f\u0131kl\u0131 ortamlarda g\u00f6rememeye ba\u015flamakt\u0131r. Eksiklik \u00e7ocuklarda k\u00f6rl\u00fc\u011fe neden olabilen ve \u00f6nlenebilen bir durumdur. Bu vitaminin yetersizli\u011fi g\u00f6r\u00fclen bireyler demir eksikli\u011fine de e\u011filimlidir. Yetersizlik, \u00f6zellikle ishal, k\u0131zam\u0131k gibi enfeksiyonlardan \u00f6lme riskini artt\u0131rmaktad\u0131r. A vitamini eksikli\u011finde g\u00f6r\u00fclen hastal\u0131klar b\u00f6yle \u00f6zetlenebilir.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"A_Vitamini_Eksikligi_Riski_Tasiyan_Bireyler\"><\/span><strong>A Vitamini Eksikli\u011fi Riski Ta\u015f\u0131yan Bireyler<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<h3><span class=\"ez-toc-section\" id=\"Premature_Bebekler\"><\/span><strong><em>Premat\u00fcre Bebekler<\/em><\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Geli\u015fmi\u015f \u00fclkelerde bebeklerde bu vitamininin eksikli\u011fine \u00e7ok s\u0131k rastlanmaz ve rastland\u0131\u011f\u0131nda bunun sebebi genellikle emilim bozukluklar\u0131 olur. Fakat premat\u00fcre bebeklerin karaci\u011fer kapasiteleri yeterince vitamin depolayacak d\u00fczeyde de\u011fildir ve plazma retinol seviyeleri ya\u015famlar\u0131n\u0131n ilk y\u0131l\u0131nda d\u00fc\u015f\u00fck seyreder. A vitamini eksikli\u011fi bulunan premat\u00fcre bebekler g\u00f6z, kronik akci\u011fer ve gastrointestinal sistem hastal\u0131klar\u0131 riski ta\u015f\u0131rlar.<\/p>\n<p><strong><em>Geli\u015fmekte Olan \u00dclkelerdeki Bebek ve \u00c7ocuklar<\/em><\/strong><\/p>\n<p>Geli\u015fmi\u015f \u00fclkelerde anne s\u00fct\u00fcnde bulunan A vitamini miktar\u0131 ilk 6 ay boyunca bebe\u011fin ihtiyac\u0131n\u0131 kar\u015f\u0131layabilecek seviyelerdedir. Fakat A vitamini eksikli\u011fi bulunan kad\u0131nlarda, anne s\u00fct\u00fcnde bulunan A vitamini miktar\u0131 da d\u00fc\u015f\u00fck olaca\u011f\u0131ndan bebe\u011fin yeterince almas\u0131 m\u00fcmk\u00fcn olamamaktad\u0131r. Bu durumun sonucunda en s\u0131k g\u00f6r\u00fclen hastal\u0131k xeroftalmiad\u0131r.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Gelismekte_Olan_Ulkelerdeki_Hamile_ve_Emziren_Kadinlar\"><\/span><strong><em>Geli\u015fmekte Olan \u00dclkelerdeki Hamile ve Emziren Kad\u0131nlar<\/em><\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Hamile kad\u0131nlar, bebe\u011fin geli\u015fmesi, dokular\u0131n olu\u015fabilmesi ve kendi metabolizmalar\u0131n\u0131n desteklenebilmesi i\u00e7in daha fazla A vitaminine ihtiya\u00e7 duymaktad\u0131r. D\u00fcnya Sa\u011fl\u0131k \u00d6rg\u00fct\u00fc\u2019n\u00fcn verilerine g\u00f6re, 9.8 milyon kad\u0131n A vitamini eksikli\u011fine ba\u011fl\u0131 olarak xeroftalmia hastal\u0131\u011f\u0131ndan muzdariptir. A vitamini eksikli\u011finin hamile ve emziren kad\u0131nlar \u00fczerindeki di\u011fer etkileri ise, artm\u0131\u015f bebek \u00f6l\u00fcmleri, artm\u0131\u015f anemi riski, daha yava\u015f ger\u00e7ekle\u015fen bebek b\u00fcy\u00fcme ve geli\u015fmesidir.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Kistik_Fibrozis_Olan_Bireyler\"><\/span><strong><em>Kistik Fibrozis Olan Bireyler<\/em><\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Kistik Fibrozis hastal\u0131\u011f\u0131 olan bireylerin \u00e7o\u011fu yetersiz pankreas aktivitesi y\u00fcz\u00fcnden, A vitaminini emebilme konusunda sorun ya\u015famaktad\u0131r. Yap\u0131lan birka\u00e7 \u00e7al\u0131\u015fma, kistik fibrozis hastalar\u0131n\u0131n %15-40\u2019\u0131n\u0131n A vitamini eksikli\u011fine sahip oldu\u011funu g\u00f6stermi\u015ftir. Fakat pankreatik aktivitenin artmas\u0131n\u0131 sa\u011flayan tedaviler ve do\u011fru beslenme uygulamalar\u0131yla bir\u00e7ok kistik fibrozis hastas\u0131 A vitamini yetersizli\u011finin \u00fcstesinden gelebilmektedir. Baz\u0131 \u00e7al\u0131\u015fmalar, oral A vitamini deste\u011finin, serum beta-karoten miktar\u0131n\u0131 d\u00fczeltebilece\u011fini \u00f6ne s\u00fcrmektedir.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"A_Vitamini_ve_Genel_Saglik\"><\/span><strong>A Vitamini ve Genel Sa\u011fl\u0131k<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<h3><span class=\"ez-toc-section\" id=\"Kanser\"><\/span><strong><em>Kanser<\/em><\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>A vitamini h\u00fccre b\u00fcy\u00fcmesinde rol ald\u0131\u011f\u0131 i\u00e7in \u00e7e\u015fitli kanser t\u00fcrleriyle aras\u0131ndaki ili\u015fkiyi inceleyen \u00e7al\u0131\u015fmalar yap\u0131lm\u0131\u015ft\u0131r.<\/p>\n<p>\u00d6rne\u011fin birka\u00e7 \u00e7al\u0131\u015fma, daha \u00f6nce hi\u00e7 sigara i\u00e7memi\u015f, \u015fu an sigara i\u00e7en ve ge\u00e7mi\u015fte sigara i\u00e7mi\u015f bireyleri incelemi\u015f ve hepsinde, karetonoidlerin, meyve ve sebzelerin fazla t\u00fcketilmesinin akci\u011fer kanseri riskini azaltt\u0131\u011f\u0131n\u0131 ortaya koymu\u015ftur.\u00a0 Fakat klinik \u00e7al\u0131\u015fmalar, beta-karoten veya A vitamini takviyesinin akci\u011fer kanserinden korunmaya bir etkisinin olmad\u0131\u011f\u0131n\u0131 s\u00f6ylemektedir. CARET (Carotene and Retinol Efficacy) \u00e7al\u0131\u015fmas\u0131nda 18,314 sigara i\u00e7en ve ge\u00e7mi\u015fte sigara i\u00e7mi\u015f kat\u0131l\u0131mc\u0131n\u0131n 4 y\u0131l boyunca her g\u00fcn 30 mg beta karoten ve 25,000 IU retinil palmitat i\u00e7eren takviyeler almalar\u0131 istenmi\u015ftir. Buna benzer di\u011fer iki \u00e7al\u0131\u015fmada A vitamini i\u00e7eren takviyelerin 5-8 y\u0131l ve 12 y\u0131l boyunca t\u00fcketilmesi g\u00f6zlemlenmi\u015ftir. Bu \u00fc\u00e7 \u00e7al\u0131\u015fman\u0131n sonu\u00e7lar\u0131na g\u00f6re, farkl\u0131 formlardaki hi\u00e7bir A vitamini takviyesi akci\u011fer kanserini \u00f6nlemekte etkili olmam\u0131\u015ft\u0131r. Hatta bu \u00e7al\u0131\u015fmalardan ikisi beta karoten ve beta karoten + retinil palmitat i\u00e7eren takviyeler alan bireylerin akci\u011fer kanserine yakalanma risklerinin artt\u0131\u011f\u0131n\u0131 saptam\u0131\u015ft\u0131r.<\/p>\n<p>Beta karoten ve prostat kanseri aras\u0131nda kurulan ili\u015fki biraz karma\u015f\u0131kt\u0131r. CARET \u00e7al\u0131\u015fmas\u0131na g\u00f6re, g\u00fcnl\u00fck olarak takviye alan kat\u0131l\u0131mc\u0131lar\u0131n, takviye almayan bireylere g\u00f6re, agresif olmayan prostat kanserine yakalanma riski %35 oran\u0131nda daha az bulunmu\u015ftur. Fakat yap\u0131lan di\u011fer \u00e7al\u0131\u015fmalardan biri prostat kanserinden kurtulmak ve hayatta kalmak i\u00e7in bu takviyelerin olumlu bir etkisinin bulunmad\u0131\u011f\u0131n\u0131 ileri s\u00fcrm\u00fc\u015ft\u00fcr.\u00a0 Hatta bu \u00e7al\u0131\u015fman\u0131n sonu\u00e7lar\u0131na g\u00f6re, \u00e7al\u0131\u015fma ba\u015flang\u0131c\u0131nda daha y\u00fcksek serum retinol seviyelerine sahip erkeklerin %20 oran\u0131nda daha fazla prostat kanseri geli\u015ftirme riski bulundu\u011fu ortaya konmu\u015ftur.<\/p>\n<p>CARET ve ATBC \u00e7al\u0131\u015fmalar\u0131n\u0131n sonu\u00e7lar\u0131na g\u00f6re, y\u00fcksek dozda beta-karoten (retinil palmitat i\u00e7eren veya i\u00e7ermeyen) daha \u00f6nce sigara i\u00e7mi\u015f veya \u015fimdi i\u00e7en ve \u00e7al\u0131\u015fma ortam\u0131nda asbeste maruz kalan bireylerde tehlikeli etkilere sebep olmaktad\u0131r.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Yaslanmaya_Bagli_Makuler_Dejenerasyon\"><\/span><strong><em>Ya\u015flanmaya Ba\u011fl\u0131 Mak\u00fcler Dejenerasyon<\/em><\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Mak\u00fcler Dejenerasyon, ileri ya\u015flardaki bireylerin g\u00f6rme kayb\u0131 ya\u015famas\u0131n\u0131n en \u00f6nemli sebeplerinden biridir. Bu hastal\u0131\u011f\u0131n tam olarak neden kaynakland\u0131\u011f\u0131 bilinmese de oksidatif stresin \u00f6nemli bir rol oynad\u0131\u011f\u0131 d\u00fc\u015f\u00fcn\u00fclmektedir. Karotenoidlerin, beta karotenin, luteinin ve zeaksantinin antioksidan etkilerinin oksidatif stres konusunda etkili oldu\u011fu d\u00fc\u015f\u00fcn\u00fclmektedir.<\/p>\n<p>AREDS (The Age-Related Eye Disease Study) \u00e7al\u0131\u015fmas\u0131na g\u00f6re, \u015fiddetli ya\u015flanmaya ba\u011fl\u0131 mak\u00fcler dejenerasyon riskinin 5 y\u0131l boyunca s\u00fcrd\u00fcr\u00fclen ve 15 mg beta-karoten, 400 IU E vitamin, 500 mg C vitamini, 80 mg \u00e7inko, i\u00e7eren g\u00fcnl\u00fck takviyelerle %25 oran\u0131nda d\u00fc\u015f\u00fcr\u00fcld\u00fc\u011f\u00fc saptanm\u0131\u015ft\u0131r. Bunu takip eden AREDS2 \u00e7al\u0131\u015fmas\u0131 da bu takviye kar\u0131\u015f\u0131m\u0131ndan beta-karotenin \u00e7\u0131kar\u0131lmas\u0131n\u0131n \u015fiddetli ya\u015flanmaya ba\u011fl\u0131 mak\u00fcler dejenerasyonu \u00f6nlemek konusunda bir etkinin bulunmad\u0131\u011f\u0131n\u0131 ortaya koymu\u015ftur. Sonu\u00e7lar\u0131n daha detayl\u0131 analizine g\u00f6re, zeaksantin ve lutein i\u00e7eren takviye kar\u0131\u015f\u0131m\u0131 geli\u015fmi\u015f ya\u015fa ba\u011fl\u0131 mek\u00fcler dejenerasyon riskini d\u00fc\u015f\u00fcr\u00fcrken, beta-karoten i\u00e7eren takviye kar\u0131\u015f\u0131m\u0131nda b\u00f6yle bir etkiye rastlanmam\u0131\u015ft\u0131r.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Kizamik\"><\/span><strong><em>K\u0131zam\u0131k<\/em><\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>K\u0131zam\u0131k geli\u015fmekte olan \u00fclkelerde \u00e7ocuk \u00f6l\u00fcmlerine en \u00e7ok neden olan hastal\u0131klardan biridir. K\u0131zam\u0131k kaynakl\u0131 ya\u015fanan \u00f6l\u00fcmlerin neredeyse yar\u0131s\u0131 Afrika\u2019da ger\u00e7ekle\u015fmektedir. Fakat bu hastal\u0131k yaln\u0131zca d\u00fc\u015f\u00fck ekonomik profillere sahip \u00fclkelerde g\u00f6r\u00fclmemektedir. A vitamini eksikli\u011fi \u015fiddetli k\u0131zam\u0131\u011fa neden olan fakt\u00f6rlerden biridir. D\u00fcnya Sa\u011fl\u0131k \u00d6rg\u00fct\u00fc, A vitamini eksikli\u011finin y\u00fcksek prevelansa sahip oldu\u011fu b\u00f6lgelerde ya\u015fayan, 1 ya\u015f ve \u00fcst\u00fc k\u0131zam\u0131k \u00e7ocuklar\u0131n 2 g\u00fcn boyunca 200,000 IU A vitamini takviyesi almas\u0131 gerekti\u011fini s\u00f6ylemektedir.<\/p>\n<p>Yap\u0131lan \u00e7al\u0131\u015fmalar\u0131 de\u011ferlendiren bir derleme makalesine g\u00f6re, k\u0131zam\u0131k olan 2 ya\u015f alt\u0131ndaki \u00e7ocuklar\u0131n 2 g\u00fcn boyunca 200,000 IU A vitamini takviyesi almalar\u0131n\u0131n, pnom\u00f6niye ba\u011fl\u0131 \u00f6l\u00fcm riskini azaltt\u0131\u011f\u0131 saptanm\u0131\u015ft\u0131r. Bu \u00e7al\u0131\u015fmalarda kullan\u0131lan A vitamini dozlar\u0131, al\u0131nabilecek \u00fcst limitin \u00e7ok \u00fcst\u00fcndedir. Bu y\u00fczden geli\u015fmi\u015f \u00fclkelerdeki yeterli miktarda A vitamini al\u0131m\u0131n\u0131n \u00e7er\u00e7evesinde, k\u0131zam\u0131k hastas\u0131 olan \u00e7ocuklarda kullan\u0131lacak A vitamini dozlar\u0131 bu kadar y\u00fcksek olmayacakt\u0131r.<\/p>\n<p>\u00d6zellikle protein ve enerji malnutrisyonu ya\u015fayan k\u0131zam\u0131k hastas\u0131 bireylerde, A vitamini eksikli\u011fi k\u00f6rl\u00fc\u011fe neden olabilir. Yukar\u0131da bahsedilen derleme makalesinde incelenen \u00e7al\u0131\u015fmalar\u0131n hi\u00e7biri \u00e7ocuklarda k\u00f6rl\u00fc\u011fe rastlamam\u0131\u015ft\u0131r fakat klinik ara\u015ft\u0131rmalar, Afrika\u2019daki k\u0131zam\u0131k \u00e7ocuklar\u0131n 130\u2019unda A vitamini eksikli\u011fine ba\u011fl\u0131 olarak, yar\u0131m g\u00f6rme kayb\u0131na ve korneada \u00fclserlere rastlanm\u0131\u015ftr.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"A_Vitamini_Fazlaligi_ve_Zehirlenmesi\"><\/span><strong>A Vitamini Fazlal\u0131\u011f\u0131 ve Zehirlenmesi<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>A vitamini ya\u011fda \u00e7\u00f6z\u00fcnen bir vitamin oldu\u011fundan v\u00fccut fazla olan\u0131n\u0131 depolamaktad\u0131r. Bu depolama i\u015flemi \u00f6ncelikli olarak karaci\u011ferde ger\u00e7ekle\u015fmektedir. \u00d6nceden olu\u015fmu\u015f olan formu ciddi anlamda zehirleyici bir etkiye sahipken (hipervitaminozis A olarak bilinen durum), y\u00fcksek miktarda beta karoten ve di\u011fer provitamin A karetinoidlerinin bu denli b\u00fcy\u00fck yan etkileri bulunmam\u0131\u015ft\u0131r. Hipervitaminozis A durumunun geli\u015fmesi fazla al\u0131m\u0131n miktar\u0131na ve s\u0131kl\u0131\u011f\u0131na ba\u011fl\u0131d\u0131r. Kronik ve y\u00fcksek doz A vitamini al\u0131m\u0131, kafa i\u00e7indeki bas\u0131nc\u0131 artt\u0131r\u0131r, yorgunlu\u011fa, ba\u015f d\u00f6nmesine, ba\u015f a\u011fr\u0131lar\u0131na, deri iritasyonlar\u0131na, kemik ve eklemlerde a\u011fr\u0131ya, koma ve hatta \u00f6l\u00fcme neden olabilir. A vitamini zehirlenmesi, besinlerle al\u0131nan vitaminin fazla olmas\u0131yla da ger\u00e7ekle\u015febilirken, \u00e7o\u011funlukla bu durum tedavilerde kullan\u0131lan ila\u00e7lar\u0131n y\u00fcksek miktarda retinoid i\u00e7ermesine ba\u011fl\u0131 olarak g\u00f6r\u00fcl\u00fcr. Bireyler bu vitamini \u00e7ok y\u00fcksek miktarda ald\u0131klar\u0131nda, depolanan k\u0131sm\u0131n\u0131n dokulardan at\u0131lmas\u0131 uzun bir zaman alabilir ve karaci\u011ferde ger\u00e7ekle\u015fen hasar her zaman geri d\u00f6nd\u00fcr\u00fclemez.<\/p>\n<p>Baz\u0131 g\u00f6zlemsel ara\u015ft\u0131rmalar, \u00f6nceden olu\u015fmu\u015f formunun al\u0131m\u0131n\u0131n y\u00fcksek olmas\u0131n\u0131 (G\u00fcnde 1,500 mikrogramdan fazla) kemik mineral yo\u011funlu\u011funun azalmas\u0131 ve buna ba\u011fl\u0131 kemiklerin k\u0131r\u0131lmas\u0131n\u0131n kolayla\u015fmas\u0131 ile ili\u015fkilendirmi\u015ftir.<\/p>\n<p>\u00d6nceden olu\u015fmu\u015f formunun al\u0131m\u0131n\u0131n y\u00fcksek olmas\u0131 ve sentetik retinoidler i\u00e7eren ila\u00e7larla yap\u0131lan tedaviler konjenital do\u011fum anomalileriyle ili\u015fkilendirilmi\u015ftir. Bu anomaliler, bebe\u011fin g\u00f6zlerinde, kafa tas\u0131nda, akci\u011ferlerinde ve kalbinde farkl\u0131 \u015fekillenmeler g\u00f6r\u00fclmesine neden olabilir. Hamile olma ihtimali olan kad\u0131nlar\u0131n y\u00fcksek dozda A vitamini almamalar\u0131 gerekmektedir. Hatta hamile kalmaya karar vermi\u015f kad\u0131nlar\u0131n y\u00fcksek dozda i\u00e7eren takviye veya ila\u00e7lar almamaya \u00f6zen g\u00f6stermesi gerekmektedir. Bu y\u00fczden <a href=\"https:\/\/coskumutlu.com\/hamilelikte-yapilmasi-gereken-hersey\/\" target=\"_blank\" rel=\"noopener noreferrer\">hamilelikte<\/a> A vitamini dikkat edilmesi gerekilen bir noktad\u0131r.<\/p>\n<p>\u00d6nceden olu\u015fmu\u015f formuna k\u0131yasla beta karoten bu kadar toksik etkilere sahip de\u011fildir ve \u00fcreme faaliyetlerine zarar vermesine dair bir bilgi bulunmamaktad\u0131r. Hatta y\u00fcksek dozda beta karoten takviyesi (20-30 mg\/g\u00fcn) veya y\u00fcksek miktarda beta karoten i\u00e7eren besinlerin \u00e7ok fazla t\u00fcketilmesi de zehirlenme vakalar\u0131n\u0131n g\u00f6r\u00fclmesine neden olmam\u0131\u015ft\u0131r. Beta karotenin uzun s\u00fcreli ve y\u00fcksek dozda kullan\u0131m\u0131na dair en \u00e7ok g\u00f6r\u00fclen etki karotenodermiad\u0131r. Bu durum zarars\u0131zd\u0131r ve derinin sar\u0131-turuncu bir renk almas\u0131na neden olur. Beta karoten t\u00fcketiminin azalt\u0131lmas\u0131yla beraber deri normal rengine d\u00f6ner.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Tolere_Edilebilir_A_Vitamini_Ust_Limitleri\"><\/span><a href=\"https:\/\/ods.od.nih.gov\/Health_Information\/Dietary_Reference_Intakes.aspx\" target=\"_blank\" rel=\"noopener noreferrer\">Tolere Edilebilir<\/a> A Vitamini \u00dcst Limitleri<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><strong>Tablo 2: A Vitamini Al\u0131m\u0131 \u00dcst Limitleri (FNB Verileri)<\/strong><\/p>\n<table>\n<tbody>\n<tr>\n<td width=\"75\"><strong>Ya\u015f<\/strong><\/td>\n<td width=\"91\"><strong>Erkek<\/strong><\/td>\n<td width=\"91\"><strong>Kad\u0131n<\/strong><\/td>\n<td width=\"91\"><strong>Hamilelik<\/strong><\/td>\n<td width=\"91\"><strong>Emzirme<\/strong><\/td>\n<\/tr>\n<tr>\n<td width=\"75\">0\u201312 ay<\/td>\n<td width=\"91\">600 mcg RAE<\/p>\n<p>(2,000 IU)<\/td>\n<td width=\"91\">600 mcg RAE<\/p>\n<p>(2,000 IU)<\/td>\n<td width=\"91\"><\/td>\n<td width=\"91\"><\/td>\n<\/tr>\n<tr>\n<td width=\"75\">1\u20133 ya\u015f<\/td>\n<td width=\"91\">600 mcg RAE<\/p>\n<p>(2,000 IU)<\/td>\n<td width=\"91\">600 mcg RAE<\/p>\n<p>(2,000 IU)<\/td>\n<td width=\"91\"><\/td>\n<td width=\"91\"><\/td>\n<\/tr>\n<tr>\n<td width=\"75\">4\u20138 ya\u015f<\/td>\n<td width=\"91\">900 mcg RAE<\/p>\n<p>(3,000 IU)<\/td>\n<td width=\"91\">900 mcg RAE<\/p>\n<p>(3,000 IU)<\/td>\n<td width=\"91\"><\/td>\n<td width=\"91\"><\/td>\n<\/tr>\n<tr>\n<td width=\"75\">9\u201313 ya\u015f<\/td>\n<td width=\"91\">1,700 mcg RAE<\/p>\n<p>(5,667 IU)<\/td>\n<td width=\"91\">1,700 mcg RAE<\/p>\n<p>(5,667 IU)<\/td>\n<td width=\"91\"><\/td>\n<td width=\"91\"><\/td>\n<\/tr>\n<tr>\n<td width=\"75\">14\u201318 ya\u015f<\/td>\n<td width=\"91\">2,800 mcg RAE<\/p>\n<p>(9,333 IU)<\/td>\n<td width=\"91\">2,800 mcg RAE<\/p>\n<p>(9,333 IU)<\/td>\n<td width=\"91\">2,800 mcg RAE<\/p>\n<p>(9,333 IU)<\/td>\n<td width=\"91\">2,800 mcg RAE<\/p>\n<p>(9,333 IU)<\/td>\n<\/tr>\n<tr>\n<td width=\"75\">19+ ya\u015f<\/td>\n<td width=\"91\">3,000 mcg RAE<\/p>\n<p>(10,000 IU)<\/td>\n<td width=\"91\">3,000 mcg RAE<\/p>\n<p>(10,000 IU)<\/td>\n<td width=\"91\">3,000 mcg RAE<\/p>\n<p>(10,000 IU)<\/td>\n<td width=\"91\">3,000 mcg RAE<\/p>\n<p>(10,000 IU)<\/td>\n<\/tr>\n<tr>\n<td width=\"75\"><\/td>\n<td width=\"91\"><\/td>\n<td width=\"91\"><\/td>\n<td width=\"91\"><\/td>\n<td width=\"91\"><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>Yukar\u0131da belirtilen limitler hayvansal besinlerden elde edilen\u00a0ve tamamen retinol veya ester formlar\u0131ndan olu\u015fan takviyelere g\u00f6re belirlenmi\u015ftir. Bir\u00e7ok multivitamin i\u00e7eri\u011finde retinol veya ester formunda bulunmaktad\u0131r. \u00d6rne\u011fin 10,000 IU i\u00e7erdi\u011fi belirtilen bir takviyede kayna\u011f\u0131n %60\u2019\u0131 beta karotenden veya di\u011fer provitamin A\u2019lardan olu\u015fuyorsa ve %40\u2019\u0131 retinol veya retinil esterlerden olu\u015fuyorsa, bu takviyenin riskli olan k\u0131sm\u0131 4,000 IU\u2019ten ibarettir. Bu miktar 0-13 ya\u015f aras\u0131 \u00e7ocuklar\u0131n \u00fcst limitinden fazlad\u0131r fakat, ad\u00f6lesan ve yeti\u015fkinlerin \u00fcst limitinin alt\u0131nda bir de\u011ferdir.<\/p>\n<p>Sonu\u00e7 olarak bu vitamin \u00f6zellikle ba\u011f\u0131\u015f\u0131kl\u0131k sistemini g\u00fc\u00e7lendiren besinler t\u00fcketen bireylerin yeterince alabilece\u011fi bir vitamindir. Ya\u015fam\u0131n devam\u0131 i\u00e7in olduk\u00e7a \u00f6nemli olan bu mikro besin \u00f6\u011fesi A vitamini i\u00e7eren kremler, A vitamini i\u00e7eren yiyecekler ve ila\u00e7lar yoluyla insan v\u00fccuduna girmektedir.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>A V\u0130TAM\u0130N\u0130 NED\u0130R? A vitamini ya\u011fda \u00e7\u00f6z\u00fcnen retinol, retinal ve retinil esterler gibi bir grup retinoide verilen isimdir. Retinoid nedir sorusuna verilebilecek en iyi cevap, retinoik asit k\u00f6kenli bile\u015fikler olduklar\u0131d\u0131r. \u00d6zellikle bir\u00e7ok kozmetik \u00fcr\u00fcnde bulunan bir bile\u015fik olan retinol nedir sorusunun cevab\u0131 ise, retinol\u00fcn de bir t\u00fcr retinoid olmas\u0131d\u0131r. Peki ya A vitamini faydalar\u0131 nelerdir?&#8230;<\/p>\n","protected":false},"author":2,"featured_media":2114,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[44],"tags":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v22.5 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>A Vitamini Hakk\u0131nda Bilinmesi Gereken Her \u015eey - Diyetisyen Co\u015fku Mutlu<\/title>\n<meta name=\"description\" content=\"Di\u011fer t\u00fcm vitaminler gibi A vitamini de insan v\u00fccudu i\u00e7in hayati olabilecek bir\u00e7ok mekanizmada g\u00f6rev almaktad\u0131r. \u00d6zellikle g\u00f6z sa\u011fl\u0131\u011f\u0131 i\u00e7in \u00f6nemli olan A vitamini ya\u011fda \u00e7\u00f6z\u00fcnen bir vitamin oldu\u011fundan, v\u00fccutta depolanabilmektedir. 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