What the Authoritative Sources Say About B12 Deficiency and Supplementation The National Institutes of Health Office of Dietary Supplements publishes the most thorough citation-backed overview of vitamin B12 its role in red blood cell formation and neurological function, the populations most at risk for deficiency (older adults, people on long-term metformin or proton pump inhibitors, vegetarians and vegans, people who have had gastric bypass surgery), and the recommended daily intake at each life stage
Chalmers JN, Shinton NK
A vitamin B12 deficiency can lead to megaloblastic anemia, a condition characterized by a low number of red blood cells that are larger than normal ( Megaloblastic anemia can cause a variety of symptoms and side effects, including ( shortness of breath headache heart palpitations fatigue poor balance memory loss That said, being low in vitamin B12 doesnt always lead to megaloblastic anemia, and many people may only experience mild symptoms like fatigue ( Furthermore, while a deficiency in vitamin B12 may not cause weight gain, it can decrease energy levels and contribute to fatigue, making it harder to stay active and manage your weight
15 , e108
If a day is missed, the research-sensible response is simply to resume the next scheduled dose, not to double up, because there is no acute deficit to make good and doubling only departs from the documented figure
