Vitamin A

Vitamin A yivitamin enyibilikayo enamafutha egcinwa esibindini.

Zimbini iintlobo zevithamini A ezifumaneka kukutya.

• Uvithamini A ogqityiweyo ufumaneka kwiimveliso zezilwanyana ezinje ngenyama, intlanzi, iinkukhu kunye nokutya kobisi.
• IProvitamin A ifumaneka kukutya okusekwe kwizityalo ezifana neziqhamo kunye nemifuno. Uhlobo oluqhelekileyo lwe-pro-vitamin A yi-beta-carotene.

I-Vitamin A ikwafumaneka kwizongezo zokutya. Ihlala ivela kwifom ye-retinyl acetate okanye i-retinyl palmitate (i-vitamin A esele yenziwe), i-beta-carotene (provitamin A) okanye indibaniselwano ye-preformed kunye ne-provitamin A.

Vitamin A inceda ifom kunye nokugcina amazinyo asempilweni, amathambo kunye nezicwili ezithambileyo, inwebu yencindi, kunye nolusu. Ikwabizwa ngokuba yi-retinol kuba ivelisa ii-pigment kwi-retina yeso.

I-Vitamin A ikhuthaza ukubona kakuhle, ngakumbi ekukhanyeni okuphantsi. Ikwanendima yokukhulelwa okusempilweni kunye nokuncancisa.

Vitamin A ifumaneka ngeendlela ezimbini:

• I-Retinol: I-Retinol yindlela esebenzayo ye-vitamin A. Ifumaneka kwisibindi sezilwanyana, ubisi olupheleleyo, kunye nokutya okuqinisiweyo.
• ICarotenoids: IiCarotenoids zinemibala emnyama (imibala). Zifumaneka kukutya kwezityalo ezinokuthi zijike zibe luhlobo olusebenzayo lwevithamini A. Kukho ngaphezu kwe-500 carotenoids eyaziwayo. Enye ye-carotenoid yi-beta-carotene.

I-Beta-carotene yi-antioxidant. Antioxidants zikhusela iiseli kumonakalo obangelwe zizinto ezibizwa ngokuba ziiradical radicals.

Iiradicals simahla kukholelwa ukuba:

• Igalelo kwizifo ezithile zexesha elide
• Dlala indima ekwaluphaleni

Ukutya imithombo yokutya ye-beta-carotene kunokunciphisa umngcipheko womhlaza.

Izongezelelo zeBeta-carotene azibonakali ukunciphisa umngcipheko womhlaza.

I-Vitamin A ivela kwimithombo yezilwanyana, njengamaqanda, inyama, ubisi oluqinileyo, itshizi, ukhilimu, isibindi, izintso, ikhowudi kunye neoyile yeentlanzi ye-halibut.

Nangona kunjalo, uninzi lwale mithombo, ngaphandle kweVitamin A yobisi olunqatyisiweyo, luphezulu kunamafutha kunye necholesterol.

Eyona mithombo ilungileyo ye vithamini A yile:

• Ikhowudi yeoyile yesibindi
• Amaqanda
• Ukutya okuziinkozo kwasekuseni okuqinisiweyo
• Ubisi olunqatyisiweyo
• Imifuno eluhlaza kunye neziqhamo
• Eminye imithombo ye-beta-carotene enjenge-broccoli, isipinatshi, kunye nohlaza oluhlaza, imifuno enamagqabi

Eyona nzulu kumbala wesiqhamo okanye imifuno, kokukhona inyusa isixa se-beta-carotene. Imithombo yemifuno ye-beta-carotene ityebile kwaye ayina-cholesterol. Ukufakwa kwabo kuphuculwe ukuba le mithombo ityiwa ngamanqatha.

INTSHAYELELO:

Ukuba awufumani vithamini A eyaneleyo, unengozi enkulu yeengxaki zamehlo ezinje:

• Ukubuyiselwa kobumfama ebusuku
• Umonakalo we-corneal ongaguqukiyo obizwa ngokuba yi-xerophthalmia

Ukungabikho kwe-vitamin A kunokukhokelela kwi-hyperkeratosis okanye ulusu olomileyo, olunamaxolo.

UKUTHENGA OKUPHAKAMILEYO:

Ukuba ufumana ivithamini A eninzi, unokugula.

• Amanani amakhulu evithamini A anokubangela iziphene zokuzalwa.
• I-Vitamin A enobuthi ityhefu ihlala yenzeka xa umntu omdala ethatha amawaka alishumi e-IU ye-vitamin A.
• I-vitamin A engapheliyo inetyhefu inokwenzeka kubantu abadala abahlala bethatha ngaphezulu kwama-25,000 IU ngosuku.

Iintsana nabantwana bachaphazeleka kakhulu ku-vithamini A. Banokugula emva kokuthatha iidosi ezincinci zevithamini A okanye iivithamin A ezinemveliso efana ne-retinol (efumaneka kwizithambiso zolusu).

Amanani amaninzi e-beta-carotene awuyi kukugula. Nangona kunjalo, amanani aphezulu e-beta-carotene anokujika ulusu lube tyheli okanye iorenji. Umbala wolusu uya kubuyela esiqhelweni wakube unciphise ukutya kwakho i-beta-carotene.

Eyona ndlela yokufumana iimfuno zemihla ngemihla zeevithamini ezibalulekileyo kukutya iintlobo ngeentlobo zeziqhamo, imifuno, ukutya okunefisi yobisi, iimbotyi (iimbotyi ezomisiweyo), iilentile, kunye neenkozo ezipheleleyo.

IBhodi yokuTya kunye neZondlo yeZiko lezeMpilo-Ukungeniswa kweReferensi yokutya (i-DRIs) Ukungeniswa okucetyiswayo kwabantu abane-vitamin A:

Iintsana (ukutya okuphakathi)

• Iinyanga ezi-0 ukuya kwezi-6: ii-micrograms ezingama-400 ngosuku (mcg / ngosuku)
• Iinyanga ezi-7 ukuya kwezi-12: 500 mcg / ngosuku

Isibonelelo seDiary esivunyelweyo (i-RDA) seevithamini kukuba uninzi lwevithamini nganye uninzi lwabantu kufuneka lufumane usuku ngalunye. I-RDA yeevithamini inokusetyenziselwa iinjongo zomntu ngamnye.

Abantwana (RDA)

• 1 ukuya kwiminyaka emi-3: 300 mcg / ngosuku
• Iminyaka emi-4 ukuya kwe-8: 400 mcg / ngosuku
• Iminyaka eli-9 ukuya kweli-13: 600 mcg / ngosuku

Ulutsha kunye nabantu abadala (i-RDA)

• Amadoda aneminyaka eli-14 nangaphezulu: 900 mcg / ngosuku
• Abasetyhini abaneminyaka eli-14 nangaphezulu: 700 mcg / ngosuku (kubafazi abaneminyaka eli-19 ukuya kwengama-50, 770 mcg / usuku ngexesha lokukhulelwa kunye ne-1,300 mcg / ngosuku ngexesha lokuncancisa)

Ingakanani ivithamini nganye oyifunayo kuxhomekeke kubudala bakho kunye nesini. Ezinye izinto, njengokukhulelwa kunye nempilo yakho, nazo zibalulekile. Buza umboneleli wakho wezempilo ukuba yeyiphi idosi ekulungeleyo.

I-Retinol kwakhona; I-retinal; I-asidi yeRetinoic; IiCarotenoids

• Isibonelelo seVitamin A.
• Vitamin A umthombo

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URoss CA. Ukusilela kweVitamin A kunye nokugqitha. Ku: Kliegman RM, St Geme JW, Blum NJ, Shah SS, Tasker RC, Wilson KM, ii-eds. Incwadi kaNelson yeNcwadi yePediatrics. Umhla wama-21. IPhiladelphia, PA: Elsevier; 2020: isahluko 61.

USalwen MJ. Iivithamini kunye nokulandela umkhondo. Ku: McPherson RA, Pincus MR, ii-eds. Ukuchongwa kweKlinikhi kaHenry kunye noLawulo ngeendlela zeLebhu. Umhla we-23. ISt Louis, MO: Elsevier; I-2017: isahluko 26.

Ke YT. Ukusilela kwezifo kwinkqubo yemithambo-luvo. Ku: Daroff RB, Jankovic J, Mazziotta JC, Pomeroy SL, ii-eds. I-Neurology kaBradley kwiKlinikhi yokuziqhelanisa. Umhla wesi-7. IPhiladelphia, PA: Elsevier; 2016: isahluko 85.