Are you aware of any recent or on-going studies looking at the use of oral vitamin B12 compared with oral B12? There was an on-going study in Madrid, but no results are available.
It has been introduced as a safe and effective form of B12 supplementation even in patients with gastrectomy. Please refer to: GE Port J Gastroenterol. 2018 Apr;25(3):117-122
The world of micronutrients still has many gaps, and the specific case of vitamin b12 is particularly complex given the clinical importance of its levels, which are low, but also high. In this sense, in complement to the debate question, I want to share with you the following manuscript detailing the aspects associated with high levels of vitamin b12.
Article Hipervitaminosis B12 una mirada desde la atención primaria