View clinical trials related to Vitamin B12 Absorption.
Filter by:Vitamin B12 is naturally present in animal products, but it could be added to plant-based products through fermentation using the Propionibacterium freudenreichii bacterium. This study aims to investigate the absorption of vitamin B12 synthesized by Propionibacterium freudenreichii from products made with fermented faba bean. The study products are wheat breads of which 30 % of the dry weight has been replaced with fermented faba bean flour. One of the study breads contains vitamin B12 produced by P. freudenreichii bacteria, and the other bread (control bread) is fermented using L. brevis bacteria (does not produce vitamin B12). The participants will eat the study bread for two consecutive days during the study weeks, with a washout period of 12 days. Fasting blood samples are collected on day 1 before administration of the first dose of vitamin B12 and on day 3. Nutrient intake and food consumption will be analyzed from 3-day food records at the baseline and on the bread eating days. The study is carried out in a double-blinded crossover setting.
In the present study the design of the vitamin B12 absorption test, CobaSorb, is further optimised. We investigate which test – measurement of holotranscobalamin or cobalamins – could be used for reflection of vitamin B12 absorption. Furthermore, we prolong the duration of vitamin B12 administration in order to determine the final duration of the vitamin B12 absorption test CobaSorb. Seventy-eight healthy individuals (age 21-81 years) are treated with three oral doses of 9 microgram cyanocobalamin per day for five successive days. Non-fasting blood samples are collected on day 1-5 before administration of the first dose of vitamin B12 and on day 8. Cobalamins and holotranscobalamin are measured on day 1–5 and 8. The performance of the vitamin B12 absorption test will be evaluated in individuals with borderline or low levels of holotranscobalamin or cobalamins (below the 75% percentiles) using a change larger than 2CV(day to day) of holotranscobalamin (22%) and cobalamins (12%) to indicate a change caused by absorption of the administered vitamin B12.