The overwhelming consensus in the mainstream nutrition community, as well as among vegan health professionals, is that plant foods do not provide vitamin B12. Despite this, some vegan advocates still believe that plant foods provide all the nutrients necessary for optimal health and, therefore, do not address vitamin B12 when promoting the vegan diet. Other vegan advocates acknowledge the need ...

In this contribution we investigated the correlation between plasma vitamin B12 levels and cognitive impairment in Alzheimer's disease. We could demonstrate a significant inverse correlation when the MMSE scores of those patients with the lowest 10% Vitamin B12 plasma levels (<184 ng/ml) were compared with the upper 10% Vitamin B12 plasma levels (>598 ng/ml): p=0.008, Spearman-Rho= -0.36. MMSE ...

Porphyra yezoensis (Susabinori, an edible purple laver), which was cultured aseptically for 12 weeks and then lyophilized, contained 50+/-2 microg/g of vitamin B(12) per 100 g dry weight. Coenzyme forms of vitamin B(12) (about 60% of the total vitamin B(12)) were found in the cultured purple laver aseptically, which may have the ability to biosynthesize the coenzymes.

Vitamin B12 concentration was determined by radioassay in 179 healthy volunteers between the ages of 20 and 93 years in order to determine whether vitamin B12 levels decline with advancing age. The authors found no statistically significant decline in vitamin B12 levels in older individuals, nor a difference between males and females. A review of previous reports identifies potential reasons fo...