Cross sectional study of vitamin B12 supplementation in Slovak and Czech vegans.

Background: The number of vegans in the world is growing and in Slovakia and the Czech Republic they make up 1% of the population. Vegan diet excludes all foods of animal origin and vegans who do not use vitamin B12 supplements are at risk of the vitamin B12 deficiency.

Objective: The aim of this study was to determine what proportion of Czech and Slovak vegans use vitamin B12 supplements regularly, irregularly or not at all and what is their supplemental cobalamin intake.

Materials and methods: The research involved 1337 self-identified vegans from Slovakia and the Czech Republic who were interviewed using the CAWI (Computer-Assisted Web Interview) method. Participants were recruited by posts in veganism-themed social media groups.

Results: Out of 1337 vegans 55.5% supplemented cobalamin regularly, 32.54% irregularly and 11.97% were not supplementing. Rate of not supplementing individuals was 5.04% higher in Slovaks than in Czechs. Short-term vegans had a significantly higher rate of not supplementing individuals (17.99%) compared to medium-term (8.37%) and long-term vegans (7.50%). Mean weekly cobalamin intake from supplements was 2938.34±2566.60 μg in regularly supplementing vegans compared to 1630.31±1949.27 μg in irregularly supplementing vegans, particularly due to the lower weekly supplementation frequency among irregularly (2.93) compared to regularly supplementing vegans (5.27).

Conclusions: The rate of supplementation in Slovak and particularly Czech vegans was higher than in other countries. The number of not supplementing individuals was significantly higher among short-term vegans, indicating that there is still a need for education on the importance of adequate and regular cobalamin supplementation, especially in new vegans. Our results support the hypothesis that the reason for higher rate of cobalamin deficiency in irregularly compared to regularly supplementing vegans is the lower cobalamin intake caused by lower supplementation frequency.