Table 1 lists the current RDAs for vitamin B12 [ 1]. For adults, the main criterion that the FNB used to establish the RDAs was the amount needed to maintain a healthy hematological status and serum vitamin B12 levels. For infants age 0 to 12 months, the FNB established an AI that is equivalent to the mean intake of vitamin B12 in healthy, breastfed infants. Table 1: Recommended Dietary Allowances (RDAs) for Vitamin B12 [ 1] Age Vitamin B12 is naturally present in foods of animal origin, including fish, meat, poultry, eggs, and dairy products [ 5]. In addition, fortified breakfast cereals and fortified nutritional yeasts are readily available sources of vitamin B12 that have high bioavailability [ 12, 13]. What’s more, though low vitamin B12 levels can have detrimental effects on newborns, it appears that high levels of the vitamin can as well. One study found that elevated blood levels of vitamin B12 in mothers increased the risk of autism in their newborns ( 28). It is essential to carefully read the ingredient list and nutrition facts panel of a supplement to know which ingredients and how much of each ingredient is included, relative to the recommended daily value of that ingredient. Please bring the supplement label to a healthcare provider to review the different ingredients contained in the supplement and any potential interactions between these ingredients and other supplements and medications you are taking. Carmel R. How I treat cobalamin (vitamin B12) deficiency. Blood 2008;112:2214-21. [ PubMed abstract]

If you choose to take vitamin A, avoid taking more than 10,000 IU to prevent toxicity. Since the nutrient is fat-soluble, it can build up in your body. Vitamin A toxicity can cause: More evidence is needed to clarify whether high or low intakes of vitamin B12 influence the risk of cancer as well as the role of vitamin B12 in preventing cancer. Cardiovascular disease and stroke If you prefer the ease of tablets and are looking for an extra little boost of calcium, HUM B12 Turbo can help meet your needs. These vegan tablets provide 1,000 mcg of vitamin B12 as methylcobalamin when you take one tablet daily with food. These tablets are also free from artificial colors, preservatives, flavors, and the major allergens. Stabler SP. Vitamin B12. In: Marriott BP, Birt DF, Stallings VA, Yates AA, eds. Present Knowledge in Nutrition. 11th ed. Washington, DC: Elsevier; 2020:257-71. There are several forms of vitamin B12, including cyanocobalamin, which is the most common, as well as adenosylcobalamin, methylcobalamin, and hydroxycobalamin.

8. Common questions about cyanocobalamin

The Dry Eye Assessment and Management Study Research Group. (2018). N-3 fatty acid supplementation for the treatment of dry eye disease. All vegans should have a reliable source of B12 whether that comes from a supplement or fortified foods like non-dairy milk, tofu, and nutritional yeast. Fortified foods and supplements are the only reliable source of vitamin B12 in a vegan diet,” says Geiger. These lozenges contain 1,000 mcg of methylcobalamin each. They are lemon flavored and also contain xylitol, a sugar alcohol, for added sweetness. Though the small amount in these supplements will likely not pose an issue, some people find that sugar alcohols do not sit well with them. The third party certifications we can trust are: ConsumerLab.com, NSF, and USP. However, these certifications are difficult to obtain and/or expensive for manufacturers, so many companies choose not to get their products tested by one of these three organizations.

Overall, the available evidence suggests that supplementation with vitamin B12 alone or in combination with other B-vitamins does not reduce the risk of CVD or of CVD-related death. Dementia and cognitive function Laird E, O'Halloran AM, Molloy AM, Healy M, Hernandez B, O'Connor D, Kenny RA, Briggs R. Low vitamin B12 but not folate is associated with incident depressive symptoms in community-dwelling older adults: a 4 year longitudinal study. Br J Nutr. 2021 Dec 13:1-22. [ PubMed abstract] Melse-Boonstra A. Bioavailability of micronutrients from nutrient-dense whole foods: zooming in on dairy, vegetables, and fruits. Front Nutr. 2020;7:101. doi:10.3389/fnut.2020.00101 This is because although many of the symptoms improve with treatment, some problems caused by the condition can be irreversible. Causes of a vitamin B12 or folate deficiency

Do I Need a Supplement? 

It can be hard to figure out if your B12 levels are too low, since the symptoms are broad and not always extremely noticeable. Symptoms include fatigue, weakness, low appetite, weight loss, and pernicious or megaloblastic anemia. Over time, a vitamin B12 deficiency can cause permanent damage to the nervous system, so if you notice tingling in the hands and feet, this could also be a risk. It’s abundant in animal-based foods, including beef, salmon, and dairy products. Some other foods may be fortified with it. Yang C-H, et al. (2018). Impact of oral vitamin D supplementation on the ocular surface in people with dry eye and/or low serum vitamin D. Average daily intakes of vitamin B12 from food are 5.94 mcg for men age 20 and older and 3.78 mcg for women [ 31]. For children age 2–19, mean daily intakes of vitamin B12 from food range from 3.76 mcg to 4.55 mcg [ 31]. Nevertheless, there have been rare reports of people experiencing severe allergic reactions to vitamin B12 supplements.