How prevalent is vitamin B-12 deficiency among vegetarians?

作者：Pawlak Roman^*; Parrott Scott James; Raj Sudha; Cullum Dugan Diana; Lucus Debbie

来源：Nutrition Reviews, 2013, 71(2): 110-117.

DOI：10.1111/nure.12001

• cobalamin
• deficiency
• vegetarians
• vegans
• vitamin B-12

Vegetarians are at risk for vitamin B-12 (B-12) deficiency due to suboptimal intake. The goal of the present literature review was to assess the rate of B-12 depletion and deficiency among vegetarians and vegans. Using a PubMed search to identify relevant publications, 18 articles were found that reported B-12 deficiency rates from studies that identified deficiency by measuring methylmalonic acid, holo-transcobalamin II, or both. The deficiency rates reported for specific populations were as follows: 62% among pregnant women, between 25% and almost 86% among children, 21-41% among adolescents, and 11-90% among the elderly. Higher rates of deficiency were reported among vegans compared with vegetarians and among individuals who had adhered to a vegetarian diet since birth compared with those who had adopted such a diet later in life. The main finding of this review is that vegetarians develop B-12 depletion or deficiency regardless of demographic characteristics, place of residency, age, or type of vegetarian diet. Vegetarians should thus take preventive measures to ensure adequate intake of this vitamin, including regular consumption of supplements containing B-12.

• 出版日期2013-2