RESUMO
Summary Objective: To consolidate information available on the effect of vitamin B12 on bone mineral density and fracture risk, with emphasis on clinical trials, observational and longitudinal data conducted in humans. Method: A systematic review of the literature of the past decade on the role of vitamin B12 in bone mineral density and fracture risk in subjects of all ages and both sexes was performed by means of a PubMed, Science Direct, Medline and SciELO database search. Articles included in this review were identified using the search terms: B12 Vitamin and Bone Mineral Density and Vitamin B12 and Risk of Fractures. Evidence quality of the included articles was evaluated by GRADE system. Results: A total of 25 original studies were identified. After reviewing the titles and abstracts of articles, only 17 articles met the inclusion criteria. The present review provides evidence that the role of vitamin B12 on bone mineral density or fracture risk should be further elucidated. Controversies are explained by heterogeneity of methodologies used for the diagnosis of vitamin B12 and also by differences among populations investigated on the studies. Conclusion: A real effect of vitamin B12 deficiency in bone health and the mechanisms associated with bone metabolism is not well established yet. It is extremely important to carry out more clarifying studies about this theme, especially with vulnerable groups such as postmenopausal and elderly women, as is well-known that they are greatly affected by deficiency of this vitamin.
Resumo Objetivo: Consolidar as informações disponíveis acerca dos efeitos da vitamina B12 sobre a densidade mineral óssea e o risco de fraturas, com destaque para ensaios clínicos, dados observacionais e longitudinais realizados com humanos. Método: Foi realizada uma revisão sistemática da literatura dos últimos dez anos sobre o papel da vitamina B12 na densidade mineral óssea e no risco de fraturas em populações de todas as idades e para ambos os sexos, com busca de artigos nos bancos de dados eletrônicos: PubMed, Science Direct, Medline e SciELO. Como estratégia de busca de dados incluíram-se os descritores: B12 Vitamin and Bone Mineral Density e B12 Vitamin and Risk of Fractures. A qualidade das evidências dos artigos incluídos foi avaliada pelo sistema GRADE. Resultados: Após a análise dos títulos e dos resumos dos artigos, a estratégia de busca resultou em 25 referências, das quais 17 artigos preencheram os critérios de elegibilidade. Esta revisão fornece evidências de que o papel da vitamina B12 sobre a densidade mineral óssea ou o risco de fraturas ainda precisa ser mais bem elucidado. As controvérsias encontram respaldo na heterogeneidade das metodologias utilizadas para o diagnóstico da vitamina B12 e também na variedade de populações presentes entre os estudos. Conclusão: Ainda não está bem estabelecido o real impacto da deficiência de vitamina B12 na saúde dos ossos e sobre os mecanismos associados ao metabolismo ósseo. É de suma importância a realização de mais estudos esclarecedores, principalmente em grupos vulneráveis como as mulheres pós-menopausa e os idosos, grupos estes bastante afetados pela deficiência dessa vitamina.
Assuntos
Humanos , Masculino , Feminino , Adulto , Vitamina B 12/administração & dosagem , Deficiência de Vitamina D/prevenção & controle , Densidade Óssea/efeitos dos fármacos , Fraturas Ósseas/prevenção & controle , Fatores de Risco , Ensaios Clínicos como Assunto , Suplementos NutricionaisRESUMO
OBJECTIVE: To consolidate information available on the effect of vitamin B12 on bone mineral density and fracture risk, with emphasis on clinical trials, observational and longitudinal data conducted in humans. METHOD: A systematic review of the literature of the past decade on the role of vitamin B12 in bone mineral density and fracture risk in subjects of all ages and both sexes was performed by means of a PubMed, Science Direct, Medline and SciELO database search. Articles included in this review were identified using the search terms: B12 Vitamin and Bone Mineral Density and Vitamin B12 and Risk of Fractures. Evidence quality of the included articles was evaluated by GRADE system. RESULTS: A total of 25 original studies were identified. After reviewing the titles and abstracts of articles, only 17 articles met the inclusion criteria. The present review provides evidence that the role of vitamin B12 on bone mineral density or fracture risk should be further elucidated. Controversies are explained by heterogeneity of methodologies used for the diagnosis of vitamin B12 and also by differences among populations investigated on the studies. CONCLUSION: A real effect of vitamin B12 deficiency in bone health and the mechanisms associated with bone metabolism is not well established yet. It is extremely important to carry out more clarifying studies about this theme, especially with vulnerable groups such as postmenopausal and elderly women, as is well-known that they are greatly affected by deficiency of this vitamin.
