Unknown long-term effects : There is no long-term safety data for either compound used individually in the general population, let alone in combination
Where does it come from
Many patients without a clinical deficiency experience improved energy and focus with supplemental B12
Importantly, neurological symptoms such as tingling, numbness, or unusual sensations are more commonly associated with B12 deficiency rather than excess
Clinical trials commonly start with 1 mg weekly and gradually increase the dose to higher levels such as 4 mg, 8 mg, or even 12 mg depending on the study protocol
These include fortified breakfast cereals, plant-based milk alternatives (soya, almond, oat), nutritional yeast, and some meat substitutes