The recommended dietary allowance (RDA) for B12 depends on age, gender, and life stage, but generally, adults require about 2.4 micrograms per day
They contain medications designed to help reduce appetite and promote weight loss
Long term use of acid lowering agents may lead to Vitamin B12 deficiency
Shaver adds: "These natural remedies often contain the vitamins discussed above or have antioxidant properties to reduce stress, and thus aging, on the hair follicle, but they will not reverse hair that has already grayed." The bottom line Whether you've gone gray prematurely or right on time, there are currently no proven foods, vitamins, hair products, natural remedies or any other treatments that permanently reverse gray hair
"Tolterodine and tamsulosin for treatment of men with lower urinary tract symptoms and overactive bladder: a randomized controlled trial"