Vitamin A: Bhenefiti, Kushomeka, Toxicity uye Zvimwe

Zvemukati

• Chii chinonzi Vitamin A?
• Mabasa muMuviri Wako
• Hutano Kubatsirwa
• Anogonesa Antioxidant
• Zvakakosha kune Hutano Hweziso uye Inodzivirira Macular Degeneration
• Inogona Kudzivirira Kune Dzimwe Gomarara
• Inokosha Kubereka uye Kuvandudza Fetus
• Inowedzera immune System Yako
• Kushayikwa
• Zvokudya Zvinyorwa
• Uturu uye Dosage Kurudziro
• Icho Chinokosha

Vitamin A chinhu chine mafuta akanyungudika icho chinoita basa rakakosha mumuviri wako.

Izvo zviripo zvakasikwa muzvikafu zvaunodya uye zvinogona zvakare kudyiwa kuburikidza nekuwedzera.

Ichi chinyorwa chinokurukura vhitamini A, kusanganisira mabhenefiti ayo, manyuko ezvekudya, pamwe nemhedzisiro yekushomeka uye chepfu.

Chii chinonzi Vitamin A?

Kunyangwe vhitamini A inowanzoonekwa seyakafanana noutano, ndiro zita chairo reboka remafuta-akanyungudika makomputa, kusanganisira retinol, retinal uye retinyl esters ().

Kune marudzi maviri e vitamini A anowanikwa mune chikafu.

Yakagadzirwa vhitamini A - retinol uye retinyl esters - inoitika chete mune zvigadzirwa zvemhuka, senge dairy, chiropa nehove, nepo provitamin A carotenoids yakawanda muzvikafu zvezvirimwa semichero, miriwo nemafuta ().

Kuti uashandise, muviri wako unofanirwa kushandura ese ari maviri mavitamini A kuita retinal uye retinoic acid, mafomu anoshanda evhitamini.

Nekuti vhitamini A ine mafuta akanyungudika, inochengetwa munyama yemuviri kuti ishandise gare gare.

Mazhinji evitamin A mumuviri wako anochengetwa muchiropa chako muchimiro che retinyl esters ().

Aya esters anobva apwanywa kuita ese-trans-retinol, inosunga kune retinol inosunga protein (RBP). Iyo inopinda muropa rako, panguva iyo muviri wako unogona kuishandisa ().

Vitamin A ndiro izwi rakajairika reboka remafuta-akanyungudika makomputa anowanikwa mune zvese zvipfuyo nemiti yekudya.

Mabasa muMuviri Wako

Vitamin A yakakosha kune hutano hwako, inotsigira kukura kwesero, immune immune, fetus kukura uye kuona.

Zvichida rimwe remabasa anozivikanwa evhitamini A ibasa raro muchiratidzo uye hutano hwemaziso.

Retinal, chimiro chinoshanda chevhitamini A, inosangana neprotein opsin kuti iite rhodopsin, morekuru rinodiwa pakuona kwemavara uye kuona kwakaderera-chiedza ().

Iyo inobatsirawo kuchengetedza nekuchengetedza iyo cornea - iyo yekunze yakatetepa yeziso rako - uye iyo conjunctiva - yakatetepa membrane inovhara pamusoro peziso rako uye mukati memaziso ako ().

Pamusoro pezvo, vhitamini A inobatsira kuchengetedza epamusoro matukisi senge ganda rako, ura, mapapu, dundira uye nzeve yemukati.

Iyo inotsigira immune immune nekutsigira kukura uye kugoverwa kweT-maseru, rudzi rwechena ropa reropa rinodzivirira muviri wako kubva kuhutachiona ().

Uyezve, vhitamini A inotsigira maseru eganda ane hutano, kubereka kwevanhurume nevanhukadzi uye kukura kwechibereko ().

Vitamin A inodikanwa kune hutano hwemaziso, kuona, immune immune, kukura kwesero, kubereka uye kukura kwe fetus.

Hutano Kubatsirwa

Vitamin A chinhu chakakosha chinovaka muviri chinobatsira hutano munzira dzakawanda.

Anogonesa Antioxidant

Provitamin A carotenoids senge beta-carotene, alpha-carotene uye beta-cryptoxanthin ndivo vanofanotungamira vhitamini A uye vane antioxidant zvivakwa.

Carotenoids inorwira mahara radicals - anonyanya kuita mamorekuru ayo anogona kukuvadza muviri wako nekugadzira oxidative kusagadzikana ().

Kushushikana nekushushikana kwakabatanidzwa nezvirwere zvakasiyana-siyana zvisingaperi zvakaita seshuga, gomarara, chirwere chemwoyo uye kudzikira kwekuziva ().

Kudya kwakakwira mu carotenoids kunoenderana nenjodzi yakaderera yezvakawanda zveizvi mamiriro, senge chirwere chemoyo, kenza yemapapu uye chirwere cheshuga (,,).

Zvakakosha kune Hutano Hweziso uye Inodzivirira Macular Degeneration

Sezvambotaurwa pamusoro apa, vhitamini A yakakosha pakuona uye hutano hwemaziso.

Kudya kwakaringana kwevhitamini A kunobatsira kudzivirira kubva kune zvimwe zvirwere zvemaziso, senge zera-rakabatana macular degeneration (AMD).

Zvidzidzo zvinoratidza kuti huwandu hweropa hwakakwira hwe beta-carotene, alpha-carotene uye beta-cryptoxanthin inogona kudzora njodzi yako ye AMD kusvika pa25% ().

Uku kuderedzwa kwenjodzi kwakabatana necarotenoid michere 'kudzivirirwa kwemacular tishu nekudzikisa huwandu hweiyo oxidative kusagadzikana.

Inogona Kudzivirira Kune Dzimwe Gomarara

Nekuda kweayo antioxidant ehupfumi, michero ine carotenoid-yakawanda uye miriwo inogona kudzivirira kubva kune mamwe marudzi ekenza.

Semuenzaniso, ongororo mune vanhu vanopfuura zviuru gumi vakafunga kuti vanosvuta vane mwero wepamusoro weropa wealpha-carotene uye beta-cryptoxanthin vane 46% uye 61% panjodzi yakaderera yekufa nekenza yemapapu, zvichiteerana, pane vasingaputi vane yakaderera kudya yeizvi zvinovaka muviri ().

Zvakare, bvunzo-chubhu zvidzidzo zvinoratidza kuti retinoids inogona kutadzisa kukura kwemamwe maseru egomarara, senge dundira, zamu uye ovarian cancer ().

Inokosha Kubereka uye Kuvandudza Fetus

Vitamin A yakakosha pakuzvara kwevarume nevakadzi nekuti inoita chinzvimbo mukukura kwerume nemazai.

Izvo zvakare zvakakosha kune placental hutano, fetal tishu kukura uye kugadzirisa, pamwe nekukura kwechibereko ().

Naizvozvo, vhitamini A inoenderana nehutano hwaamai nevechibereko uye nevaya vanoedza kubata nhumbu.

Inowedzera immune System Yako

Vitamin A inokanganisa hutano hwemuviri nekusimudzira mhinduro dzinodzivirira muviri wako kubva kuzvirwere nezvirwere.

Vitamin A inobatanidzwa mukugadzirwa kwemamwe maseru, anosanganisira B- uye T-maseru, anotamba epakati mumhinduro dzemuviri dzinochengetedza chirwere.

Kushomeka kweichi chinovaka kunotungamira kune akawedzera mwero wema pro-anogumbura mamorekuru ayo anoderedza immune system kupindura uye basa ().

Vitamin A inokanganisa hutano nekuchengeta oxidative kusagadzikana mukutarisa, kuwedzera immune system yako uye kudzivirira pane zvimwe zvirwere.

Kushayikwa

Kunyangwe kushomeka kwevhitamini A kusingawanzoitika munyika dzakasimukira senge US, zvakajairika munyika dzichiri kusimukira, sezvo vanhu ava vangave vasina mukana wekuwana zvekudya zve preformed vhitamini A uye provitamin A carotenoids.

Kushomeka kweVitamin A kunogona kutungamira kumatambudziko akakomba ehutano.

Sekureva kweWHO, kushomeka kwevhitamini A ndiko kunonyanya kukonzera kupofu kunodzivirika muvana pasirese.

Kushomeka kweVitamin A kunowedzerawo kuomarara uye njodzi yekufa nezvirwere zvakaita segwirikwiti nemanyoka (,).

Pamusoro pezvo, kushomeka kwevhitamini A kunomutsa mukana wekupererwa neropa uye kufa kune vakadzi vane nhumbu uye zvinokanganisa chibereko nekudzora kukura uye kukura ().

Zviratidzo zvishoma zvakakomba zvevhitamini A kushomeka zvinosanganisira nyaya dzeganda senge hyperkeratosis uye acne (,).

Mamwe mapoka senge vacheche vasati vazvarwa, vanhu vane cystic fibrosis uye vakadzi vane nhumbu kana vanoyamwisa munyika dzichiri kusimukira vane njodzi yekushomeka kwevhitamini A ().

Kushayikwa kweVitamin A kunogona kutungamira kuhupofu, kuwedzera hutachiona hutachiona, kunetseka kwepamuviri uye nyaya dzeganda.

Zvokudya Zvinyorwa

Kune zvakawanda zvekudya sosi yezvose zvakafanogadzirwa vhitamini A uye provitamin A carotenoids.

Preformed vhitamini A iri nyore kupinza uye kushandiswa nemuviri wako pane kudyara-kwakavakirwa masosi eprovitamin A carotenoids.

Kukwanisa kwemuviri wako kunyatso shandura carotenoids, senge beta-carotene, kuita vhitamini A inoshanda zvinoenderana nezvinhu zvakawanda - zvinosanganisira genetics, kudya, hutano hwese nemishonga ().

Nechikonzero ichi, avo vanotevera kudya kunodyarwa nemiti - kunyanya vegans - vanofanirwa kungwarira nezvekuwana zvakakwana zvekudya zvine carotenoid.

Kudya kwakanyanya mu preformed vhitamini A ndeaya:

• Mazai emazai
• Nzombe yechiropa
• Chiropawurst
• Ruomba
• Cod chiropa mafuta
• Huku chiropa
• Salmoni
• Cheddar chizi
• Chiropa soseji
• King mackerel
• Trout

Chikafu chakakwira muprovitamin A carotenoids senge beta-carotene inosanganisira (25, 26):

• Mbatatisi
• Nhanga
• Makarotsi
• Kale
• Sipinachi
• Dandelion magidhi
• Kabichi
• Swiss chard
• Tsvuku tsvuku
• Collard magirini
• Zvishoma
• Butternut squash

Yakagadzirirwa vhitamini A inowanikwa mune zvekudya zvemhuka zvakaita sechiropa, salmon uye mazai emazai, nepo provitamin A carotenoids inowanikwa mune zvekudya zvezvirimwa, kusanganisira mbatatisi, kare uye kabichi.

Uturu uye Dosage Kurudziro

Kungofanana nekushomeka kwevhitamini A kunogona kukanganisa hutano, kuwana zvakawandisa kunogona zvakare kuve nenjodzi.

Iyo inokurudzirwa mvumo yezuva nezuva (RDA) yevhitamini A ndeye 900 mcg uye 700 mcg pazuva revarume nevakadzi, zvichiteerana - izvo zvinogona kusvikwa zviri nyore nekutevera chikafu chese-chikafu (27).

Zvisinei, zvakakosha kuti usapfuure muganho wepamusoro unoregererwa (UL) we10,000 IU (3,000 mcg) kune vanhu vakuru kudzivirira huturu (27).

Kunyangwe zvichikwanisika kutora yakawandisa preformed vhitamini A kuburikidza nemhuka-yakavakirwa sosi sechiropa, huturu hunowanzo sanganisirwa nekuwedzeredza kuwedzera kudya uye kurapwa nemimwe mishonga, yakadai seIsotretinoin (,).

Sezvo vhitamini A ine mafuta-soluble, inochengetwa mumuviri wako uye inogona kusvika kune asina hutano mazinga nekufamba kwenguva.

Kutora yakawandisa vhitamini A kunogona kutungamira kumhedzisiro mhedzisiro uye kunogona kutouraya kana ikadyiwa pamwero wakanyanya kwazvo.

Acute vhitamini A chepfu inoitika pamusoro penguva pfupi kana imwe chete, yakanyanya kuwanda dhitamini yevhitamini A inopedzwa, nepo huturu husingaperi huchiitika kana madosi anopfuura gumi kagumi iyo RDA inonwiwa kwenguva yakareba ().

Mhedzisiro inowanzoitika yehutachiona hweAvhitamini A huturu - hunowanzozonzi hypervitaminosis A - inosanganisira:

• Kuona kusagadzikana
• Kusangana pamwe uye kurwadziwa kwepfupa
• Kusadya zvakanaka
• Kusvotwa uye kurutsa
• Chiedza chezuva
• Bvudzi kurasikirwa
• Kutemwa nemusoro
• Ganda rakaoma
• Kukuvara kwechiropa
• Jaundice
• Kunonoka kukura
• Kuderedza kudya
• Kuvhiringidzika
• Itchy ganda

Kunyangwe isingawanzo kujairika kupfuura isingagumi vhitamini A chepfu, yakanyanya vhitamini A chepfu inosanganiswa nezviratidzo zvakakomba, kusanganisira kukuvara kwechiropa, kuwedzerwa kwekumanikidza uye kunyangwe kufa ().

Uyezve, vhitamini A chepfu inogona kukanganisa hutano hwaamai nevechibereko uye inogona kutungamira mukuremara kwekuzvara ().

Kuti udzivise huturu, ibva pamwero wepamusoro-vhitamini A zvinowedzera.

Iyo UL yevhitamini A inoshanda kune mhuka-based chikafu zvinyorwa zvevhitamini A, pamwe nevhitamini A zvinowedzera.

Kudya kwakanyanya kwezvikafu zvecarotenoid hakune hukama nehuturu, asi zvidzidzo zvinobatanidza beta-carotene zvinowedzera pamwe nenjodzi yakawedzera yekenza yemapapu uye chirwere chemoyo mune vanoputa ().

Sezvo zvakawandisa vhitamini A zvinogona kukuvadza, bvunza chiremba wako usati watora vhitamini A inowedzera.

Vitamin A chepfu inogona kukonzera zviratidzo, sekukuvara kwechiropa, kusagadzikana kwekuona, kuda kurutsa uye kunyangwe rufu. Yepamusoro-dose vhitamini A zvinowedzera zvinofanirwa kudzivirirwa kunze kwekunge zvatemwa nachiremba wako.

Icho Chinokosha

Vitamin A chinhu chine mafuta akanyungudika chakakosha kuita immune immune, hutano hwemaziso, kubereka uye kukura kwe "fetus".

Zvese kushomeka uye kuwandisa kwekudya kunogona kukonzera zvakakomba mhedzisiro, saka kunyangwe zvichikosha kusangana neRDA ye 700-900 mcg zuva nezuva kune vanhu vakuru, usapfuure iyo yepamusoro zuva muganho we3,000 mcg.

Kudya kune hutano, kwakaringana inzira yakanaka yekupa muviri wako huwandu hwakachengeteka hweichi chakakosha chikafu.