Vitamin B12 added as a fortificant to flour retains high bioavailability when baked in bread

Authors: Garrod, Marjorie; BUCHHOLZ, BRUCE - Livermore National Laboratory; MILLER, JOSHUA - The College Of New Jersey; HAACK, KURT - Livermore National Laboratory; GREEN, RALPH - University Of California, Davis; Allen, Lindsay - A

Submitted to: Nuclear Instruments and Methods in Physics Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/25/2018
Publication Date: 6/18/2018
Citation: Garrod, M.G., Buchholz, B.A., Miller, J.W., Haack, K.W., Green, R., Allen, L.H. 2018. Vitamin B12 added as a fortificant to flour retains high bioavailability when baked in bread. Nuclear Instruments and Methods in Physics Research. 438:136-140. https://doi.org/10.1016/j.nimb.2018.05.042.
DOI: https://doi.org/10.1016/j.nimb.2018.05.042

Interpretive Summary: Vitamin B12 de'ciency and depletion are common world-wide, particularly in populations that consume low amounts of animal source foods. WHO and the Food Forti'cation Initiative recommend that wheat 'our be forti'ed with vitamin B12 in regions where intake of B12 is low. The purpose of this pilot study in 've participants was to determine if forti'cation of 'our with B12 produced a bread product with intact B12 still present and to determine if healthy elderly absorb su'cient B12 from bread forti'ed in this manner. High-purity crystalline 14C-B12 was dissolved in water and added to 'our (2 µg B12/100 g 'our) in a bread maker and made into rolls (average 1.17 kBq (31.5 nCi) 14C-B12 in a total of 0.8 µg B12 per roll). Excess 14C 'rst appeared in plasma 4 h after ingestion of the 14C forti'ed bread and plasma levels returned almost to background by 72 h. Measurement of 14C in plasma veri'ed that the dose was absorbed into the systemic circulation. The cumulative% dose recovered in urine was 4.8–37.0% (mean = 20.1%). Most of the 14C label in the stool appeared by day 4, and the cumulative % dose recovered in stool was 24.5–43.0% (mean = 31.8%). Bioavailability among the 5 participants, calculated by subtracting the sum of urinary and fecal 14C excretion from the administered dose, was 28.4–63.7% (mean = 48.0%). This study showed that when B12 is added as a forti'cant to 'our it survives the fermentation and baking processes, and retains ~50% bioavailability when fed in small doses to healthy subjects. The Recommended Dietary Allowance of B12 for adults is 2.4 µg/d. This recommendation assumes that usual bioavailability of low doses of the vitamin in the crystalline form is 60%, while for the same amount in foods such as meat and 'sh it is 50%. Our pilot study shows that B12 added to bread as a forti'cant in 'our was absorbed as well as it is from endogenous food sources such as meat and 'sh.

Technical Abstract: Vitamin B12 de'ciency and depletion are common world-wide, particularly in populations that consume low amounts of animal source foods. WHO and the Food Forti'cation Initiative recommend that wheat 'our be forti'ed with vitamin B12 in regions where intake of B12 is low. The purpose of this pilot study in 've participants was to determine if forti'cation of 'our with B12 produced a bread product with intact B12 still present and to determine if healthy elderly absorb su'cient B12 from bread forti'ed in this manner. High-purity crystalline 14C-B12 was dissolved in water and added to 'our (2 µg B12/100 g 'our) in a bread maker and made into rolls (average 1.17 kBq (31.5 nCi) 14C-B12 in a total of 0.8 µg B12 per roll). Excess 14C 'rst appeared in plasma 4 h after ingestion of the 14C forti'ed bread and plasma levels returned almost to background by 72 h. Measurement of 14C in plasma veri'ed that the dose was absorbed into the systemic circulation. The cumulative% dose recovered in urine was 4.8–37.0% (mean = 20.1%). Most of the 14C label in the stool appeared by day 4, and the cumulative % dose recovered in stool was 24.5–43.0% (mean = 31.8%). Bioavailability among the 5 participants, calculated by subtracting the sum of urinary and fecal 14C excretion from the administered dose, was 28.4–63.7% (mean = 48.0%). This study showed that when B12 is added as a forti'cant to 'our it survives the fermentation and baking processes, and retains ~50% bioavailability when fed in small doses to healthy subjects. The Recommended Dietary Allowance of B12 for adults is 2.4 µg/d. This recommendation assumes that usual bioavailability of low doses of the vitamin in the crystalline form is 60%, while for the same amount in foods such as meat and 'sh it is 50%. Our pilot study shows that B12 added to bread as a forti'cant in 'our was absorbed as well as it is from endogenous food sources such as meat and 'sh.