Vitamin B12 Foods: Best Sources and Amounts

Vitamin B12 comes almost entirely from animal foods and fortified foods: beef liver has 70.7 mcg in 3 ounces, clams 17 mcg and cooked wild oysters 14.9 mcg, against an adult need of 2.4 mcg a day¹. Fish, beef, milk, yogurt, eggs, fortified cereal and fortified nutritional yeast fill out the list¹.

Most people in the US get enough from food: average intake is 5.84 mcg a day in men and 3.69 mcg in women¹. The people who fall short are mainly vegans, older adults who absorb B12 poorly from food, and people on long-term acid reducers or metformin¹. For the trials on vitamin B12 supplements, see our evidence page.

Organ meat and shellfish have the most B12 by far; fish, red meat and dairy are the everyday sources^{1, 2}. B12 is made only by certain bacteria, and it builds up in animal tissue, especially in ruminants such as cattle and sheep and in shellfish³.

Animal foods (per serving; % of the 2.4 mcg Daily Value where the NIH lists it)

These values come from USDA food composition data, as listed by the NIH and the USDA's own nutrient tables^{1, 2}:

• Beef liver, pan fried, 3 oz: 70.7 mcg (2,944% DV)
• Mussels, blue, raw, 1 cup: 18 mcg
• Clams, cooked, 3 oz: 17 mcg (708% DV)
• Octopus, raw, 3 oz: 17 mcg
• Oysters, eastern, wild, cooked, 3 oz: 14.9 mcg (621% DV)
• Queen crab, cooked, 3 oz: 8.8 mcg
• Pacific herring, raw, 3 oz: 8.5 mcg
• Trout, cooked, 1 fillet: 4.6 mcg
• Pink salmon, canned, 3 oz: 4.2 mcg
• Atlantic salmon, cooked, 3 oz: 2.6 mcg (108% DV)
• Tuna, light, canned in water, 3 oz: 2.5 mcg (104% DV)
• Ground beef, 85% lean, 3 oz: 2.4 mcg (100% DV)
• Lamb shoulder, cooked, 3 oz: 2.3 to 3.0 mcg
• Milk, 2%, 1 cup: 1.3 mcg (54% DV)
• Yogurt, plain, fat free, 6 oz: 1.0 mcg (43% DV)
• Cheddar cheese, 1.5 oz: 0.5 mcg (19% DV)
• Egg, whole, cooked, 1 large: 0.5 mcg (19% DV)
• Turkey breast, roasted, 3 oz: 0.3 mcg (14% DV)

A food with 20% of the Daily Value or more per serving counts as a high source¹. Liver, shellfish, most fish, beef, lamb, milk and yogurt all qualify; eggs and cheese come close.

Does chicken have vitamin B12?

Yes, but not much. Cooked dark chicken meat has about 0.46 mcg per cup, and roasted turkey breast 0.3 mcg per 3 ounces^{2, 1}. Chicken giblets are richer: the raw giblets from 1 pound of ready-to-cook chicken have 2.62 mcg².

For vegetarians, dairy, eggs and fortified foods are the reliable sources; for vegans, fortified foods and supplements are¹. Plants do not naturally contain vitamin B12, with nori a partial exception covered below^{1, 4}.

• Fortified nutritional yeast, about ¼ cup: 8.3 to 24 mcg, depending on the brand, so check the label¹
• Fortified plant milk, 8 fl oz: 3 mcg in the USDA entries for two ready-to-drink almond milks; products vary²
• Fortified breakfast cereal (25% DV), 1 serving: 0.6 mcg¹
• Milk, yogurt and eggs: 0.5 to 1.3 mcg per serving, as listed above¹
• Tempeh, ½ cup: 0.1 mcg, too little to count on¹

The B12 added to fortified foods is already in free form, so it skips the step where stomach acid releases B12 from food protein¹. Fortified cereal and nutritional yeast have high bioavailability for that reason¹.

Do seaweed, spirulina or mushrooms count?

Mostly not. A review of plant sources named dried purple laver (nori) as the most suitable natural plant source, but other edible algae contain little or none^{4, 5}. Spirulina tablets are a poor source: in one analysis, standard tests overstated their B12 6 to 9 times, and 83% of the B12-like compounds that bind intrinsic factor were pseudovitamin B12, which is inactive in humans^{6, 5}. Edible plants and mushrooms rarely contain meaningful amounts³.

Adults need 2.4 mcg of vitamin B12 a day¹. The Recommended Dietary Allowances (RDAs) are:

• Adults and teens 14 and older: 2.4 mcg
• Pregnancy: 2.6 mcg
• Breastfeeding: 2.8 mcg
• Children 9 to 13: 1.8 mcg; 4 to 8 years: 1.2 mcg; 1 to 3 years: 0.9 mcg
• Infants: 0.4 to 0.5 mcg (Adequate Intake)

Only 5% of US men and 11% of women eat less than the average requirement of 2 mcg a day from food¹. There is no upper limit for B12, because of its low potential for toxicity¹.

Eat one B12-rich food at two or three meals rather than one big dose: the absorption system that uses intrinsic factor (a protein made in the stomach) saturates at about 1.5 to 2.0 mcg per meal⁵. Beyond that, the share absorbed falls steeply¹.

A 2013 systematic review found absorption ranged from 4.5% of a 38 mcg dose from liver to 83% of a 3.0 mcg dose from mutton⁷. So a serving of liver supplies far more B12 than you absorb at that meal.

Sample days that reach 2.4 mcg

Built from the amounts above^{1, 2}:

• Omnivore: 1 egg at breakfast (0.5 mcg), a tuna sandwich with 3 oz canned light tuna (2.5 mcg) and a glass of 2% milk (1.3 mcg). Total: about 4.3 mcg.
• Vegetarian (dairy and eggs): fortified cereal with 1 cup of milk (1.9 mcg), a 6-oz yogurt (1.0 mcg) and 1 egg (0.5 mcg). Total: about 3.4 mcg.
• Vegan: fortified nutritional yeast on dinner (8.3 mcg or more per ¼ cup), plus a fortified plant milk (about 3 mcg). Check both labels, because amounts vary by brand.

Are some foods absorbed better than others?

Yes. B12 from dairy appears to be about 3 times as bioavailable as B12 from meat, fish and poultry, and B12 from supplements about 50% more than from food¹. In 5,937 Norwegian adults, B12 from dairy and fish tracked with blood levels, but B12 from meat and eggs did not⁸.

In the Framingham Offspring Study of 2,999 adults, 23% of non-users of supplements who ate no fortified cereal had B12 below 185 pmol/L, against 12% of those who ate it more than 4 times a week⁹. The figure was 24% in the lowest third of dairy intake and 13% in the highest, with no difference by meat intake⁹.

Eggs are debated. Older studies put egg B12 absorption below 9%⁵. A 2019 study in 10 adults, using labelled eggs, measured a mean of 30.2%; the amount absorbed stayed at 0.5 to 0.8 mcg (mean 0.55 mcg) across egg servings of 1.4 to 2.6 mcg¹⁰.

Diet alone falls short for vegans, and absorption falls short for many older adults and people with gut conditions or certain medicines¹. Even with enough B12 on the plate, deficiency can develop if the stomach cannot release or absorb it¹.

• Vegans and many vegetarians. A review of 40 studies found deficiency rates from 0% to 86.5% in vegetarian adults, higher in vegans, especially vegans who took no supplement¹¹. A 2024 meta-analysis of 17 studies found lower blood B12 and higher homocysteine in vegans than omnivores, and better status in vegans who supplemented¹². See our B12 for deficiency page.
• Older adults. Deficiency affects more than 20% of elderly people in one review, and food-cobalamin malabsorption (B12 stays bound to food protein) causes over 60% of cases¹³. Atrophic gastritis, which cuts stomach acid and intrinsic factor, affects 8% to 9% of adults 65 and older¹.
• People with pernicious anemia. This autoimmune condition stops intrinsic factor production, so food B12 is not absorbed even at adequate intakes¹. It needs medical treatment, not diet changes.
• People with gut disease or surgery. Celiac disease, Crohn's disease, weight-loss surgery and stomach surgery can all reduce B12 absorption¹.
• Breastfed babies of vegan mothers. They can have very limited B12 reserves and develop deficiency early, with a risk of lasting neurological damage¹.

People who cannot release B12 from food still absorb the free B12 in fortified foods and supplements normally¹. In the Framingham study, 8% of supplement users had low B12, against 20% of non-users⁹.

Long-term acid reducers and metformin are the two common ones; both are linked to lower B12 levels¹.

• Proton pump inhibitors and H2 blockers (for reflux and ulcers). In a case-control study of 25,956 people with B12 deficiency and 184,199 without, a 2-year or longer supply of a proton pump inhibitor was linked to 65% higher odds of deficiency (odds ratio 1.65), and the same supply of an H2 blocker to 25% higher odds¹⁴.
• Metformin (for type 2 diabetes and prediabetes). In the Diabetes Prevention Program, people on 850 mg twice a day had low or borderline-low B12 more often than those on placebo: 19.1% vs 9.5% at 5 years, and 20.3% vs 15.6% at 13 years¹⁵. Each additional year of metformin use was associated with 13% higher odds of deficiency¹⁵.

Acid reducers slow the release of stomach acid that frees B12 from food¹. Keep taking your medicine, and ask your clinician about a B12 blood test.

Tiredness, pale skin, a sore smooth tongue, palpitations, and numbness or tingling in the hands and feet are the classic signs¹. Deficiency causes megaloblastic anemia, in which red blood cells are too large and too few¹. Symptoms can take years to appear¹.

Nerve symptoms can occur without anemia, and the damage can become permanent, so early testing matters¹. Blood levels below 200 pg/mL are usually considered low, and a methylmalonic acid test can confirm a borderline result¹. Our B12 deficiency page covers causes and testing, and the evidence on B12 for anemia and peripheral neuropathy is on our pair pages.

Are there foods to avoid with B12 deficiency?

None of the sources we reviewed name a food that blocks B12 absorption. The documented causes are poor absorption, pernicious anemia, gut surgery, the medicines above and a diet without animal or fortified foods¹. Very large amounts of folic acid are the one dietary caution, covered next¹⁶.

Beef liver, fortified cereal and eggs supply both B12 and folate; liver and oysters supply B12 and iron^{1, 16, 17}. Folate (vitamin B9) is a different vitamin from B12; folic acid is the form added to fortified foods and supplements¹⁶.

• Beef liver, 3 oz: about 71 mcg B12, 215 mcg DFE folate (54% DV), 5 mg iron (28% DV) and 0.9 mg vitamin B6 (53% DV)^{1, 16, 17, 18}
• Oysters, cooked, 3 oz: 14.9 mcg B12 and 8 mg iron (44% DV)^{1, 17}
• Fortified breakfast cereal: often 25% of the DV for B12, folate and B6 each per serving; check the label^{1, 16, 18}
• Beef, 3 oz: 2.4 mcg B12 (ground, 85% lean) and about 2 mg iron (braised bottom round)^{1, 17}
• Tuna and salmon, 3 oz: 2.5 to 2.6 mcg B12 (canned light tuna, Atlantic salmon); fresh yellowfin tuna and sockeye salmon have 0.6 to 0.9 mg vitamin B6^{1, 18}
• Other vitamin B6 sources: chickpeas (1.1 mg per cup), chicken breast (0.5 mg per 3 oz), and potatoes and bananas (0.4 mg each), but none of them supply B12^{18, 1}
• Egg, 1 large: 0.5 mcg B12 and 22 mcg DFE folate^{1, 16}

Spinach, black-eyed peas, asparagus and Brussels sprouts are rich in folate (78 to 131 mcg DFE per serving) but contain no B12^{16, 1}. Avocado, at 59 mcg DFE per ½ cup, has the most folate of the fruits in the NIH folate table; a small orange has 29 mcg and a banana 24 mcg¹⁶. Among drinks, tomato juice (36 mcg per ¾ cup) and orange juice (35 mcg) lead¹⁶. Adults need 400 mcg DFE of folate a day¹⁶. For the evidence on supplements, see folate, iron and vitamin B6.

Can folic acid hide a B12 deficiency?

Yes, in large amounts. High folate intake can correct the anemia of B12 deficiency but not the nerve damage, so the deficiency can go unnoticed¹⁶. Experts now also worry that large amounts of folate may worsen the anemia and cognitive symptoms of B12 deficiency¹⁶. If you take high-dose folic acid, make sure your B12 intake is covered too.

Supplements in this guide

• Vitamin B12
• Folate (Vitamin B9)
• Iron
• Vitamin B6 (Pyridoxine)
• B-Complex Vitamins
• Multivitamin

A supplement makes sense when food cannot supply or your body cannot absorb enough: if you are vegan, have low stomach acid, take metformin or an acid reducer long term, or have had gut surgery^{1, 11}. Otherwise, food usually covers the 2.4 mcg¹.

• If you eat meat, fish or dairy most days: you likely get enough. A test is worth it only if you have symptoms or a risk factor above.
• If you are vegetarian: have dairy or eggs at two meals a day, and use fortified foods.
• If you are vegan: use fortified foods daily or take a supplement; reviews of vegan diets recommend a supplement¹¹.
• If you are 65 or older, or on metformin or an acid reducer: ask for a B12 test. Atrophic gastritis affects 8% to 9% of adults 65 and older¹. Fortified foods and supplements work around it, as explained above.
• If you are pregnant or breastfeeding on a vegan diet: talk to your clinician about B12 now, because your baby depends on your supply¹.

Multivitamins usually contain 5 to 25 mcg of B12, B-complex products 50 to 500 mcg, and B12-only products 500 to 1,000 mcg¹. For timing, our guide to when to take vitamins covers taking B vitamins with or without food, and our fat-soluble vs water-soluble vitamins explainer covers why B12 is stored differently.

We searched PubMed and the Firecrawl research index for systematic reviews, meta-analyses and cohort studies on dietary B12 sources, bioavailability, vegetarian and vegan status, older adults and drug interactions, and read 13 abstracts; all 13 are cited. Food amounts come from the NIH Office of Dietary Supplements fact sheets for vitamin B12, folate, iron and vitamin B6, and the USDA National Nutrient Database (SR Legacy) table of B12 per common measure, read on 15 October 2026. The tuna sandwich and other sample days are our arithmetic from those values.

What the evidence can't tell us: food B12 values for fortified products change with each brand, most absorption data come from small studies, and the blood-test cut-offs for "low" B12 differ between studies.

1. National Institutes of Health, Office of Dietary Supplements. Vitamin B12: Fact Sheet for Health Professionals. https://ods.od.nih.gov/factsheets/VitaminB12-HealthProfessional/
2. U.S. Department of Agriculture, Agricultural Research Service, National Agricultural Library. Vitamin B-12 (µg) per common measure. Source: USDA National Nutrient Database for Standard Reference Legacy (2018). https://www.nal.usda.gov/sites/default/files/page-files/Vitamin%20B-12.pdf
3. Watanabe F, et al. Vitamin B12 sources and microbial interaction. Exp Biol Med (Maywood). 2018;243(2):148-158. doi:10.1177/1535370217746612
4. Watanabe F, et al. Vitamin B₁₂-containing plant food sources for vegetarians. Nutrients. 2014;6(5):1861-73. doi:10.3390/nu6051861
5. Watanabe F. Vitamin B12 sources and bioavailability. Exp Biol Med (Maywood). 2007;232(10):1266-74. doi:10.3181/0703-MR-67
6. Watanabe F, et al. Pseudovitamin B(12) is the predominant cobamide of an algal health food, spirulina tablets. J Agric Food Chem. 1999;47(11):4736-41. doi:10.1021/jf990541b
7. Doets EL, et al. Systematic review on daily vitamin B12 losses and bioavailability for deriving recommendations on vitamin B12 intake with the factorial approach. Ann Nutr Metab. 2013;62(4):311-22. doi:10.1159/000346968 Our study summary.
8. Vogiatzoglou A, et al. Dietary sources of vitamin B-12 and their association with plasma vitamin B-12 concentrations in the general population: the Hordaland Homocysteine Study. Am J Clin Nutr. 2009;89(4):1078-87. doi:10.3945/ajcn.2008.26598
9. Tucker KL, et al. Plasma vitamin B-12 concentrations relate to intake source in the Framingham Offspring study. Am J Clin Nutr. 2000;71(2):514-22. doi:10.1093/ajcn/71.2.514
10. Garrod MG, et al. 14C-Cobalamin Absorption from Endogenously Labeled Chicken Eggs Assessed in Humans Using Accelerator Mass Spectrometry. Nutrients. 2019;11(9). doi:10.3390/nu11092148
11. Pawlak R, et al. The prevalence of cobalamin deficiency among vegetarians assessed by serum vitamin B12: a review of literature. Eur J Clin Nutr. 2014;68(5):541-8. doi:10.1038/ejcn.2014.46
12. Niklewicz A, et al. A systematic review and meta-analysis of functional vitamin B12 status among adult vegans. Nutr Bull. 2024;49(4):463-479. doi:10.1111/nbu.12712
13. Andrès E, et al. Vitamin B12 (cobalamin) deficiency in elderly patients. CMAJ. 2004;171(3):251-9. doi:10.1503/cmaj.1031155
14. Lam JR, et al. Proton pump inhibitor and histamine 2 receptor antagonist use and vitamin B12 deficiency. JAMA. 2013;310(22):2435-42. doi:10.1001/jama.2013.280490
15. Aroda VR, et al. Long-term Metformin Use and Vitamin B12 Deficiency in the Diabetes Prevention Program Outcomes Study. J Clin Endocrinol Metab. 2016;101(4):1754-61. doi:10.1210/jc.2015-3754 Our study summary.
16. National Institutes of Health, Office of Dietary Supplements. Folate: Fact Sheet for Health Professionals. https://ods.od.nih.gov/factsheets/Folate-HealthProfessional/
17. National Institutes of Health, Office of Dietary Supplements. Iron: Fact Sheet for Health Professionals. https://ods.od.nih.gov/factsheets/Iron-HealthProfessional/
18. National Institutes of Health, Office of Dietary Supplements. Vitamin B6: Fact Sheet for Health Professionals. https://ods.od.nih.gov/factsheets/VitaminB6-HealthProfessional/