Ascorbic Acid is essential in the production of Collagen, helps build up the body's immune system and intensifies the absorption of Glutathione
If you are low in B12, you may also want to look into whether you may have other nutrient depletions as well, including depletions in iron, vitamin A, vitamin E, the B vitamins, potassium, and iodine , which are all required for proper thyroid function
Wattam AR, Gabbard JL, Shukla M, Sobral BW (2014) Comparative genomic analysis at the PATRIC, a bioinformatic resource center
Sortilin expression is essential for pro-nerve growth factor-induced apoptosis of rat vascular smooth muscle cells