One of the most common questions posed to vegetarians and vegans is, where do you get your vitamin B12 from? That’s a fair question, since the majority of this essential nutrient is found in animal products, including meats, fowl, fish, and dairy. The consequences of not getting enough vitamin B12 can be quite serious, so it’s important for everyone-vegans and non-vegans alike-to be sure they get what they need.
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Do you get enough vitamin B12?
It’s not just vegetarians and vegans who could be B12 deficient; in fact, more than 20 percent of Americans have low levels, and your chances of being vitamin B12 deficient increase with age. These figures are higher in other countries. For example, in Latin America, deficiency or marginal levels of the vitamin are seen in about 40 percent of children and adults, while 70 percent of adults in India suffer with this nutritional challenge.
Recommended daily intake of vitamin B12 is 2.4 micrograms (ug) for men and women age 14 years and older, 2.6 ug for pregnant women, and 2.8 ug for breastfeeding women. If you don’t get the recommended amount from your diet (we'll talk about food choices below), then you can choose a supplement. Before you take a supplement, however, be sure to have your vitamin B12 levels checked with a simple blood test.
What are signs and symptoms of vitamin B12 deficiency?
Even a mild deficiency of vitamin B12 can result in symptoms like low energy levels and impaired mental function. Other signs and symptoms include depression, poor memory, tingling and numbness in the hands and feet, balance and coordination problems, headaches, ringing in the ears, yellow skin, paranoia, feeling out of breath, and confusion. These symptoms can worsen as the levels of this nutrient decline in our body. That’s because vitamin B12 plays a critical role in the production of red blood cells (which is why some people with vitamin B12 deficiency experience associated anemia), brain and nervous system functioning, and the creation of DNA. It typically takes years for a vitamin B12 deficiency to become apparent, so it’s best to be vigilant about maintaining healthy levels.
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Non-vegan food sources of B12
- Clams (cooked, 1 oz; 28 ug)
- Beef liver (1 oz; 20 ug)
- Atlantic mackerel (3 oz; 7.4 ug)
- Sardines (3 oz; 6.6 ug)
- Lamb (3 oz; 2.7 ug)
- Wild salmon (3 oz; 2.6 ug)
- Tuna, light, canned in water (3 oz; 2.5 ug)
- Feta cheese (1/2 cup 1.25 ug)
- Cottage cheese (1 cup; 0.97 ug)
Vegan food sources of B12
If you are a strict vegetarian or vegan, getting enough vitamin B12 from food alone may require some dietary changes, but it’s not difficult. Here are some options:
- Algae, specifically dried green laver (Enteromorpha sp) and dried purple laver (Porphyra sp) (which are commonly sold as nori sheets and used to make sushi), reportedly contain about 63.6 ug and 32.3 ug per 3.5 oz, respectively. Other types of algae contain little to no vitamin B12.
- Fortified breakfast cereals (fortified with 100% of %DailyValue; 1 serving, 6 ug). One downside of many fortified breakfast cereals (and other vitamin B12 fortified foods) is that the vitamin has been synthesized in the lab. Other foods that are often fortified with vitamin B12 include some fruit juices, nondairy beverages, tofu, and vitamin water.
- Mushrooms (3.5 oz; 1.09-2.65 ug), including black trumpet and golden chanterelle; others such as porcini, oyster, and black morels provide 0.09 ug per 3 ounces. Dried shiitake mushrooms have been shown to contain 5.61 ug per 3.5 ounces. This finding prompted the authors of this study to state that “consumption of approximately 50 g [about 7 ounces] of dried shiitake mushroom fruiting bodies could meet the RDA for adults” but that eating that many mushrooms “would not be possible on a daily basis.”
- Nutritional yeast (1 Tbs; 2.4 ug). This can be a wonderful addition to popcorn, nondairy cheese recipes, mashed potatoes, as a topping for vegetables and cooked grains, and stirred into soups. Read labels carefully; not all nutritional yeast contains vitamin B12.
- Tempeh (3 oz; 0.7-8.0 ug; depends on the bacterial contamination during production, particularly Rhizopus spp)
Foods that have trace amounts of vitamin B12 include soybeans (non-fermented), broccoli, asparagus, mung bean sprouts, and kimchi (fermented Korean vegetables).
Vitamin B12 supplements
Vitamin B12 supplements can help both vegans and non-vegans alike. When buying B12 supplements, you will encounter two main kinds: methylcobalamin and cyanocobalamin. The former (methylcobalamin) is the preferred form because it is much better absorbed and utilized by the body. The best forms are sprays, sublingual, or liquids, as they don’t need to be digested before the body uses them. Look for products that don’t contain added sugars, food colorings, or flavoring agents.
Read more about how to take supplements properly
Sources
Allen LH. How common is vitamin B12 deficiency? American Journal of Clinical Nutrition 2009 Feb; 89(2): 693S-96SAxe J. Top 10 vitamin B12 foods. Mayo Clinic. Vitamin B12Nout MJR, Rombouts FM. Recent developments in tempe research. Journal of Applied Bacteriology 1990; 69:609-33Refsum H et al. Hyperhomocysteinemia and elevated methylmalonic acid indicate a high prevalence of cobalamin deficiency in Asian Indians. American Journal of Clinical Nutrition 2001 Aug; 74(2): 233-41Watanabe F et al. Characterization of vitamin B12 compounds in the wild edible mushrooms black trumpet (Craterellus cornucopioides) and golden chanterelle (Cantharellus cibarius) Journal of Nutritional Science and Vitaminology 2012; 58:438-41.Watanabe F et al. Dried green and purple lavers (nori) contain substantial amounts of biologically active vitamin B12 but less of dietary iodine relative to other edible seaweeds. Journal of Agriculture and Food Chemistry 1999; 47:2341-43.Watanabe F et al. Vitamin B12-containing plant food sources for vegetarians. Nutrients 2014 May; 6(5): 1861-73
