Folik Asit ve Nöral Tüp Defektleri
Özet
Vaka kontrol, kohort çalışmaları ve randomize çalışmalar da dâhil olmak üzere çok çeşitli kaynaklardan elde edilen kanıtlar, gebeliğin erken döneminde multivitamin kullanımının NTD riskini yarıdan fazla azaltabileceğini ve bu takviyelerdeki aktif faktörün öncelikle veya tamamen folik asit olduğunu belgelemiştir. Bu faydalar, birçok ülkede nüfus zenginleştirme programlarında doğrulanmıştır. Tam fayda için minimum doz tam olarak bilinmemekle birlikte, diyet kaynaklarına eklenen günlük 0,4 mg folik asitten daha az olduğu görülmektedir. Temel ilişki kurulmuş olmasına rağmen, olası gen-diyet etkileşimlerini tanımlamak, optimal besin zenginleştirme seviyesini belirlemek ve takviye programlarına B-12 vitamininin dahil edilmesinin istenip istenmeyeceğini bilmek için ek çalışmalara ihtiyaç vardır. Zenginleştirme ile ilgili kararlar, folat ve B-12 alımlarının kardiyovasküler hastalık, kanser ve bilişsel işlev riskleri üzerindeki etkilerinden güçlü bir şekilde etkilendiğinden, bu ilişkilere dair daha fazla kanıt yüksek bir önceliktir.
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