This Is How Much Vitamin B12 You Should Really Get Every Day

When it comes to micronutrients, vitamin B12 is doing a lot for your health. Also known as cobalamin, it plays many important roles in the body, including assisting with red blood cell creation, converting food into energy, boosting mood, and keeping our hair, skin, and nails looking good (via Healthline).

We don't need much B12 for optimal health. According to the National Institutes of Health (NIH), the recommended dietary allowance (RDA) for both men and women 14 and older is only 2.4 mcg. Pregnant and breastfeeding women need a bit more (2.6 mcg and 2.8 mcg, respectively), but even these amounts are easy to reach. Meat, dairy products, eggs, and fortified cereals are all excellent sources of vitamin B12. You can also get B12 in supplement form — either by itself, with other B vitamins, or as part of a multivitamin.

Because B12 is a water-soluble vitamin, it's easy for our bodies to get rid of what we don't need through our urine. So there's little need to worry about getting too much. In fact, no tolerable upper intake limit (UL) has been set for this vitamin because there's such a low risk for toxicity. Prescription-strength doses of vitamin B12, however, may not always be safe, so it's important to have a doctor following your progress if you go this route.

What happens if you don't get enough vitamin B12?

Most people get plenty of vitamin B12 from their diet. According to the National Institutes of Health (NIH), the average American gets 3.4 mcg. Some groups, however, are at greater risk of deficiency. Because meat and animal products are the best sources of vitamin B12, vegans who don't take a supplement or eat foods fortified with synthetic B12 likely aren't getting enough. Research reported by WebMD suggests that as many as 92 percent of vegans (compared to 66 percent of vegetarians and only 5 percent of omnivores) are deficient in this nutrient.

But most cases of B12 deficiency stem from problems with absorption rather than intake. The NIH cautions that low stomach acid (common among older adults), gastrointestinal disorders such as celiac and Crohn's disease, and gastrointestinal surgery can all lead to difficulty absorbing enough B12.

Harvard Health Publishing noted that because the liver can store vitamin B12, deficiency may be slow to appear. But once it does, it can produce a number of unpleasant and dangerous symptoms, including numbness and tingling, anemia, fatigue, and weakness. Severe deficiency may require vitamin B12 injections.