Intake of vitamin B12 in relation to vitamin B12 status in groups susceptible to deficiency: a systematic review

Objective: To systematically review the evidence for whether habitual or different levels of experimental intake of vitamin B12 from diet and supplements is sufficient to ensure adequate B12 status in groups most suscep- tible to vitamin B12 deficiency. Methods: We searched MEDLINE, Embase, Cochrane Central Register of Controlled Trials and Scopus up to 21 May 2021, for intervention studies, prospective cohort studies and case-control studies assessing B12 intake from diet and/or supplements...