The short answer: the foods highest in vitamin B12 are beef liver, clams, mussels, oysters and mackerel, and 3 ounces of any of them gives at least six times the Daily Value. Fish, meat, eggs, milk and yogurt are good everyday sources. Plants have no B12 unless it’s added, so vegans need fortified foods or a supplement. Most adults need 2.4 micrograms a day.
The numbers below come from the NIH Office of Dietary Supplements (ODS) and USDA FoodData Central. The Daily Value (DV) for B12 is 2.4 mcg.
What does B12 do for you?
Vitamin B12 keeps your blood cells and nerve cells healthy and helps make DNA, the genetic material in every cell. NIH says it’s needed for the development and function of the central nervous system and for making healthy red blood cells.
Without enough B12, your body can’t make normal red blood cells. That leads to megaloblastic anemia, a blood condition that NIH says makes people tired and weak. Low B12 can also damage nerves, even before anemia shows up.
What B12 doesn’t do: give you extra energy if you already get enough. NIH says B12 supplements don’t improve energy, athletic performance or endurance in people with enough B12 from their diet.
How much B12 do you need a day?
Adults and teens need 2.4 mcg of B12 a day, according to NIH. Needs rise in pregnancy and while breastfeeding.
| Life stage | B12 per day |
|---|---|
| Children 1 to 3 years | 0.9 mcg |
| Children 4 to 8 years | 1.2 mcg |
| Children 9 to 13 years | 1.8 mcg |
| Teens 14 to 18 and adults | 2.4 mcg |
| Pregnancy | 2.6 mcg |
| Breastfeeding | 2.8 mcg |
B12 has no upper limit. The Food and Nutrition Board didn’t set one because of its low potential for harm, and NIH says it’s generally considered safe even at high doses.
What foods are high in B12?
Shellfish, liver and oily fish top the list. Anything at 20% DV or more counts as a high source.
| Food | Portion | B12 (mcg) | % DV | Data |
|---|---|---|---|---|
| Nutritional yeast, fortified (varies by brand) | about ¼ cup | 8.3 to 24 | 346 to 1,000% | NIH |
| Beef liver, pan fried | 3 oz | 70.7 | 2,944% | NIH |
| Mussels, cooked | 3 oz | 20.4 | 850% | USDA |
| Clams, cooked | 3 oz | 17.0 | 708% | NIH |
| Atlantic mackerel, cooked | 3 oz | 16.1 | 673% | USDA |
| Oysters, cooked | 3 oz | 14.9 | 621% | NIH |
| Alaska king crab, cooked | 3 oz | 9.8 | 407% | USDA |
| Bluefin tuna, cooked | 3 oz | 9.2 | 385% | USDA |
| Sardines, canned in oil | 1 can (3.75 oz) | 8.2 | 343% | USDA |
| Sockeye salmon, cooked | 3 oz | 3.8 | 158% | USDA |
| Rainbow trout, farmed, cooked | 3 oz | 3.5 | 146% | USDA |
| Almond milk, fortified | 1 cup | 3.0 | 125% | USDA |
| Atlantic salmon, cooked | 3 oz | 2.6 | 108% | NIH |
| Light tuna, canned in water | 3 oz | 2.5 | 104% | NIH |
| Ground beef, 85% lean | 3 oz | 2.4 | 100% | NIH |
| Soy milk, fortified | 1 cup | 2.1 | 86% | USDA |
| Haddock, cooked | 3 oz | 1.8 | 75% | USDA |
| Tilapia, cooked | 1 fillet | 1.6 | 67% | USDA |
| Top sirloin steak, lean | 3 oz | 1.4 | 60% | USDA |
| Milk, 2% | 1 cup | 1.3 | 54% | NIH |
| Cottage cheese, 2% | 1 cup | 1.1 | 44% | USDA |
| Yogurt, plain, fat-free | 6 oz | 1.0 | 43% | NIH |
| Cod, cooked | 3 oz | 0.9 | 37% | USDA |
| Swiss cheese | 1 oz | 0.9 | 36% | USDA |
| Breakfast cereal, fortified with 25% DV | 1 serving | 0.6 | 25% | NIH |
| Pork tenderloin, roasted | 3 oz | 0.5 | 20% | USDA |
| Egg, cooked | 1 large | 0.5 | 19% | NIH |
| Cheddar cheese | 1½ oz | 0.5 | 19% | NIH |
| Turkey breast, roasted | 3 oz | 0.3 | 14% | NIH |
| Chicken breast, roasted | 3 oz | 0.3 | 12% | USDA |
USDA rows are worked out from USDA’s per-100g figures and portion weights. Fortified foods vary by brand, so check the label.
Your body also absorbs some foods better. NIH says B12 from dairy appears to be absorbed about three times better than B12 from meat, fish and poultry. Absorption also drops sharply once you go past about 1 to 2 mcg at once, so spreading B12 foods across your meals makes sense.
Beans, bananas, spinach and whole-wheat bread have no B12 at all. They’re still worth eating for other nutrients, as our lists of foods high in potassium and foods high in B6 show.
What are the best B12 foods for vegetarians and vegans?
Fortified foods are the main plant-based source, because plants don’t naturally contain B12. NIH says fortified breakfast cereals and fortified nutritional yeast are easy to find and well absorbed. The NHS adds unsweetened soy drinks fortified with B12 and yeast extracts such as Marmite.
Tempeh is often called a B12 food, but NIH lists half a cup at 0.1 mcg, just 3% DV. Vegetarians who eat dairy and eggs can get some B12 from them: a cup of milk, a yogurt and an egg add up to about 2.8 mcg.
B12 isn’t always listed on labels. The FDA only requires it when B12 has been added, so look for it on cereals, plant milks and nutritional yeast. If you eat little or no animal food, the NHS says a B12 supplement may be needed.
Who is at risk of low B12?
People who eat no animal foods, people who can’t absorb B12 well and people on certain long-term medicines are most at risk. Absorption needs stomach acid and a protein called intrinsic factor, so anything that affects your stomach or gut can get in the way.
- Vegans and vegetarians. Natural B12 comes only from animal foods. Babies breastfed by vegan mothers can also run low.
- Older adults. NIH says many don’t make enough stomach acid to absorb the B12 in food, and deficiency affects between 3% and 43% of older adults, depending on how it’s measured. NIH advises people over 50 to get most of their B12 from fortified foods or supplements, which the body can usually absorb. The NHS says B12 or folate deficiency affects about 1 in 20 people aged 65 to 74 and 1 in 10 aged 75 or over.
- Stomach and gut problems. Pernicious anemia, an autoimmune condition, stops the body making intrinsic factor. Atrophic gastritis, celiac disease, Crohn’s disease and stomach or bowel surgery, including weight-loss surgery, can also cut absorption.
- Some medicines. NIH says metformin, used for diabetes and prediabetes, might lower B12 levels, and acid reducers such as omeprazole and lansoprazole can reduce B12 absorption from food. The NHS also lists anticonvulsants. Don’t stop or change any medicine because of this. NIH suggests that people taking these regularly talk to their health care provider about their B12 status.
What are the signs of low B12?
Tiredness and weakness are the most common signs of low B12, often with pale skin. NIH and the NHS also list:
- pins and needles or numbness in your hands and feet
- a sore, red tongue or mouth ulcers
- a fast or pounding heartbeat
- loss of appetite and weight loss
- problems with balance, memory, vision or mood, including depression and confusion
Signs can be slow to appear. NIH says your body stores 1,000 to 2,000 times what you eat in a day, so symptoms of a shortage can take several years to show. Cleveland Clinic notes you may have no symptoms at all. Tiredness has many causes, so see our guide to why you might always be tired for the others.
When should you get your B12 checked?
See your doctor if you have symptoms of low B12 or belong to a higher-risk group. The NHS says early diagnosis matters because some nerve problems caused by low B12 can be permanent.
It’s a blood test. Cleveland Clinic says doctors may check a complete blood count, your B12 level, and methylmalonic acid (MMA) or homocysteine. NIH says most labs treat a B12 level below 200 or 250 pg/mL as low, and an MMA test can help confirm deficiency when B12 falls in a borderline range.
Treatment works. The NHS says most cases are easily treated with injections or tablets, and a Cochrane review cited by NIH found very high oral doses raised B12 levels about as well as injections. Your doctor will choose what fits the cause.
What should you do next?
Look at what you ate yesterday and count your B12 foods. If there were none, add one today: a can of sardines, a cup of fortified soy milk or an egg and a yogurt. If you take metformin or an acid reducer, or you don’t eat animal foods, ask your doctor about a B12 test at your next visit. Vitamin D is the other nutrient people often run short on, and our guide on how to get vitamin D covers it. For a month of meals already planned, The Menopause Meal Plan has 4 weeks of high-protein meals with grocery lists.
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Quick questions
Does B12 give you energy?
Only if you’re low. B12 helps your body make healthy red blood cells, and a shortage causes anemia that leaves you tired and weak. But NIH says B12 supplements don’t boost energy, athletic performance or endurance in people who already get enough B12 from their diet.
Can low B12 make you tired?
Yes. Tiredness and weakness are the most common signs of low B12, because a shortage causes megaloblastic anemia. The NHS also lists pins and needles, a sore red tongue, mouth ulcers and memory or mood problems. If you have these signs, see your doctor for a blood test.
What vegetarian foods are high in B12?
Dairy, eggs and fortified foods are the main vegetarian sources. NIH lists a cup of 2% milk at 1.3 mcg, a 6-ounce fat-free yogurt at 1.0 mcg and a large egg at 0.5 mcg. Fortified nutritional yeast can give 8.3 to 24 mcg in about a quarter cup, depending on the brand.
Is B12 water soluble?
Yes, vitamin B12 is a water-soluble vitamin. Even so, your body stores a large amount of it: NIH says the body holds 1,000 to 2,000 times as much as you’d typically eat in a day. That’s why symptoms of a shortage can take several years to appear.
Can you take too much B12?
Vitamin B12 has no official upper limit. The Food and Nutrition Board didn’t set one because of its low potential for harm, and NIH says B12 has not been shown to cause harm even at high doses. Your body absorbs only a small share of the large doses found in many supplements.
Are B12 shots better than tablets?
Not always. Shots are often used first to treat deficiency because they bypass absorption problems. NIH cites a Cochrane review that found very high oral doses of 1,000 to 2,000 mcg raised B12 levels about as well as injections, though the evidence was low quality. Your doctor will choose based on the cause.
This article is general information, not medical advice. If you take a regular medicine, are pregnant, or have a stomach or bowel condition, talk to your doctor before changing your diet or starting a supplement, and never stop a medicine on your own.
Sources
- NIH Office of Dietary Supplements. Vitamin B12: Fact Sheet for Health Professionals
- NIH Office of Dietary Supplements. Vitamin B12: Fact Sheet for Consumers
- USDA FoodData Central, SR Legacy data
- NHS. Vitamin B12 or folate deficiency anaemia
- NHS. The vegan diet
- Cleveland Clinic. Vitamin B12 Deficiency