People at a higher risk of B12 deficiencies include older adults, people who suffer from gastrointestinal disorders or have had gastrointestinal surgeries, and anyone who adheres to a vegan or vegetarian diet
This can lead to tiredness, weakness, and shakiness, as well as mood changes
In the same 3 mL it is only ~3,333 mcg/mL (1 unit 33.3 mcg), so the same milligram doses need roughly double the units : 250 mcg 8 units and 500 mcg 15 units
Additionally, energy pathways between minima and seams associated with crossing of S1 /S0 surfaces, are the most efficient for internal conversion (IC) to the ground state
Other common risk factors for B12 deficiency in the US include long-term use of proton pump inhibitors or H2-receptor antagonists, chronic alcoholism, and strict vegetarian or vegan diets