Vitamina B12: funções metabólicas e impactos para a saúde
DOI:
https://doi.org/10.34119/bjhrv8n3-149Keywords:
Anemia Megaloblástica, cobalamina, cofator enzimático, micronutriente, síntese de DNAAbstract
A vitamina B12 é um micronutriente hidrossolúvel necessário para o organismo humano. Ela atua como cofator enzimático em diferentes reações metabólicas fundamentais, sendo indispensável para a formação de células sanguíneas, síntese de DNA e o funcionamento adequado do sistema nervoso. A B12 é encontrada de forma natural exclusivamente em alimentos de origem animal, as principais fontes incluem carnes, peixes, frutos do mar, ovos e laticínios. Considerando sua importância essencial na célula e no metabolismo, o objetivo do presente estudo foi identificar evidências disponíveis na literatura sobre as funções metabólicas e impactos para a saúde da vitamina B12. De acordo com os achados obtidos foi possível verificar que a vitamina B12 ajuda na formação adequada dos eritrócitos, atua na manutenção da bainha de mielina, camada protetora que envolve os nervos e facilita a transmissão de sinais nervosos, influencia no metabolismo de macronutrientes (carboidratos, proteínas e gorduras), convertendo alimentos em energia, contribui para a memória e função cognitiva e também contribui no controle dos níveis de homocisteína, um aminoácido que, em excesso, está associado a maior risco de doenças cardíacas. A deficiência desse micronutriente no organismo pode causar anemia megaloblástica, alterações neurológicas e está indiretamente associada a problemas cardíacos. Diante disso, foi possível destacar o papel fundamental da vitamina B12 em processos fisiológicos primordiais do organismo.
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