Foods and Supplements Associated with Vitamin B Biomarkers among Vegetarian and Non-Vegetarian Participants of the Adventist Health Study-2 (AHS-2) Calibration Study.

To investigate the association between plasma concentration of vitamin B and B intake from supplements, fortified foods, and animal source foods among vegetarians and non-vegetarians, we conducted a cross-sectional analysis among 728 participants of the Adventist Health Study 2 (AHS-2) calibration study. The median age of participants was 58 years, 65.4% were female, and 50.3% were White. We used six 24 h dietary recalls to measure B intake, serum vitamin B, and holotranscobalamin (holoTC) concentration. B supplements had a significantly positive association with plasma B among all subjects ( trend < 0.001), especially among vegans and lacto-ovo vegetarians ( trend < 0.001). Among non-users of B supplements, B intake from milk substitutes was significantly positively associated with holoTC ( trend < 0.004) and serum B12 ( trend < 0.030). In non-vegetarians, holoTC was significantly positively associated with B intake from eggs, while serum B was significantly positively associated with B intake from milk in the upper tertile compared to the lower, and B intake from meat in the middle compared to the lower tertile intake ( < 0.011). Supplements containing B followed by B intake from milk substitutes were significant contributors of plasma vitamin B concentration.