Vitamin B12, a nutrient found mostly in animal products, is vital for healthy nerves and blood cells.
A deficiency can go unnoticed because it can cause symptoms that are shared with other conditions.
Vegans can get vitamin B12 from fortified plant milks, nutritional yeast flakes, and supplements.
Vitamin B12 deficiency — which can go unnoticed but eventually cause a range of symptoms including numb limbs and yellow skin and eyes — can be prevented by eating certain foods, according to a dietitian.
Most people in the US eat enough of the nutrient, National Institutes of Health data suggests.
However, Dr. Brad Kamitaki, an assistant professor of neurology at Rutgers Robert Wood Johnson Medical School, previously told Insider that vitamin B12 deficiency "can be undiagnosed or underdiagnosed since symptoms can be nonspecific," like fatigue, tongue swelling, palpitations, and arm or leg tingling.
Vitamin B12 deficiency typically has two causes: malabsorption, because of conditions like celiac disease, or inadequate intake.
Symptoms can take years to appear despite inadequate intake, because the body can store it.
Insider recently shared the story of a woman who woke up with pins and needles, which were caused by a severe vitamin B12 deficiency.
You don't need to track your vitamin B12 intake if you eat animal products
The vitamin is found naturally in meat, eggs, and dairy products.
Priya Tew, a registered dietitian and founder at Dietitian UK, told Insider that most people don't need to be counting or tracking their daily intake, especially if they eat animal products most days.
It's not that we have to be eating lots and lots of these foods, it's just about having some of them in your diet overall, Tew said.
The NIH recommends that the average US adult consumes 2.4 micrograms of vitamin B12 every day. For example, 3 ounces of cooked salmon or pan-fried beef contains all of the vitamin B12 that you need for the day, and a cup of 2% fat cow's milk contains half.
People may need more of the vitamin when pregnant — up to 2.6 micrograms — or breastfeeding — up to 2.8 micrograms — when the body has a higher demand for it and deficiencies may cause harm to babies, like developmental delays and anemia.
Vegans should get their vitamin B12 status checked
Vegans and those that haven't eaten eggs, dairy, and meat for more than 5 years are at risk of a vitamin B12 deficiency, according to the British Dietetic Association (BDA), and should get their status checked.
People who don't eat animal products can get vitamin B12 from fortified breakfast cereals, nutritional yeast flakes, and marmite, Tew said.
She said that it is "really important" that people who don't drink cow's milk have plant milks that are fortified with vitamin B12.
The BDA recommends that long-term vegetarians and vegans take supplements of around 10 micrograms per day as required.
Vitamin B12 is water soluble, so if you take more than the daily allowance then your body pees it out.
People should consult a doctor or dietitian before starting supplements, according to Tew, to ensure they don't have an underlying medical condition causing the deficiency and so they don't interact with other medications.
Read the original article on Insider