Vitamin B12 is one of the eight B-complex vitamins in charge of optimal health and body function. This water-soluble vitamin is critical for the proper functioning of various organs. It’s also associated with reducing the risk of certain diseases such as AMD, heart disease, and some types of cancer.
In this article, you’ll learn about the essential vitamin B12 foods (natural dietary sources of this vitamin), their function, and other helpful information regarding cobalamin.
Vitamin B12 Functions
Vitamin B12 performs a range of functions in the body. One of its most important roles is related to the conversion of carbohydrates into glucose. This process is essential for energy production. Furthermore, vitamin B12 is also in charge of the breakdown and absorption of fats and protein.
Another one of the essential vitamin B12 benefits is associated with optimal nervous system functioning. Namely, vitamin B12 is vital for maintaining nerve cell health and optimal brain function. Cobalamin also supports hair, skin, eyes, and liver health.
This essential vitamin also plays a vital role in the body’s genetic makeup by producing and regulating DNA and RNA. Besides, vitamin B12 closely interacts with folate to produce new red blood cells and supports the proper iron function.
The joint role of vitamin B12 and folate is also apparent in the immune system. Namely, these two vitamins work together to produce S-adenosylmethionine (SAMe), a vital compound for immune function.
Maintaining the cardiovascular system is also one of the benefits of vitamin B12. This vitamin joins forces with vitamins B6 and B9 to regulate homocysteine levels in the body, an amino acid linked with heart disease (either as the cause or an indicator).
The primary natural sources of cobalamin include animal products such as seafood, liver, eggs, and dairy. However, it’s surprisingly challenging to find vitamin B12 in vegetables.
Recent research shows that only a small number of vegetables and plants (some mushroom and algae species) contain cobalamin. In other words, it’s incredibly difficult (but not impossible) to find natural sources of B12 for vegan diet followers.
Let’s dive into some of the best dietary sources of this essential vitamin.
Stewed, poached, or steamed clams are highly nutritious B12 vitamin foods. A 3-oz serving of cooked clams provides a staggering 84.1 mcg (3,504% DV) of vitamin B12. On the other hand, the same amount of breaded fried clams contains less than half the cobalamin content—34.23 mcg (1,426% DV).
Moreover, clams are a good source of protein, carbs, calcium, sodium, potassium, phosphorus, vitamin A, and folate.
Oysters are also rich dietary sources of vitamin B12. For example, a 3-oz serving of canned eastern oysters provides a whopping 16.2 mcg (675% DV) of cobalamin.
On the other hand, fried eastern oysters and poached Pacific oysters offer an even higher vitamin B9 content—20.66 mcg (861% DV) and 24.48 mcg (1,020% DV), respectively.
Additionally, oysters are rich in carbohydrates, copper, selenium, zinc, and vitamin D.
Mussels are also one of the top vitamin B12 or cobalamin foods. A 3-oz serving of cooked blue mussels offers 20.4 mcg 850% DV) of cobalamin.
Additionally, mussels are rich in protein, iron, and vitamin C.
This highly nutritious mollusk also ranks high among natural cobalamin sources. Namely, you can get 15.4 mcg (642% DV) from a 3-oz serving of cooked whelks.
Whelk also contains a high amount of protein, magnesium, vitamin B6, and iron.
Alaskan King Crab
Alaskan King Crab meat is also one of the valuable foods with vitamin B12. The cobalamin content in a 3-oz serving of cooked Alaskan king crab amounts to 9.78 mcg (407%). In other words, you can get 15.4 mcg (642% DV) of vitamin B12 from a single crab leg.
Furthermore, the Alaskan king crab contains relatively high amounts of protein, vitamin A, vitamin C, phosphorus, and potassium.
This crustacean offers high cobalamin content, with a 3-oz serving providing 8.84 mcg (368% DV) of vitamin B12. In other words, you can get about 13.18 mcg (549% DV) of cobalamin per crab.
Apart from being one of the best sources of vitamin B12, Dungeness crabs offer an abundance of protein, copper, phosphorus, selenium, and niacin.
A 3-oz serving of cooked farmed crayfish provides 2.64 mcg (110% DV) of cobalamin, making it one of the rich dietary sources of vitamin B12.
Crayfish also contains a fair amount of protein, vitamin E, and minerals like zinc.
This mollusk is a top food with vitamin B12. This doesn’t come as a surprise, as 3 oz of the cooked octopus contains an astounding 30.6 mcg (1,275% DV) of cobalamin.
Octopus is also an excellent source of iron, phosphorus, and vitamin B6.
A 3-oz serving of dry-heated Atlantic mackerel contains 16.2 mcg of vitamin B12 (675% DV).
Like oysters, besides being one of the top foods rich in vitamin B12, mackerels provide various other nutrients such as niacin, vitamin B6, phosphorus, and magnesium.
A 3-oz serving of fried Atlantic herring provides 11.1 mcg (462% DV) of cobalamin.
Not only are herrings good sources of B12, but they also pack a significant amount of protein, niacin, phosphorus, vitamin D, and vitamin B6.
Fried tuna also ranks high on the list of foods high in vitamin B12, with as much as 9.26 mcg (386% DV) per 3-oz serving.
Bluefin tuna also offers a high protein, selenium, phosphorus, and potassium content.
Atlantic sardines offer 8.22 mcg (343% DV) of cobalamin per can, making them one of the good sources of B12.
Like other seafood, sardines are packed with nutrients, such as protein, iron, calcium, and omega-3s.
This fish also ranks relatively high on the list of good food sources of vitamin B12. A 3-oz serving of fried wild rainbow trout offers 5.36 mcg (223% DV) of cobalamin. This means you can get as much as 9.01 mcg (375% DV) of vitamin B12 in just one fillet.
Farmed rainbow trout provides a slightly lower vitamin B12 content—3.49 mcg (145% DV) per 3 oz or 2.92 mcg (122% DV) per fillet.
Rainbow trout is also a valuable source of protein, omega-3s, niacin, vitamin D, selenium, and vitamin B6.
This salmon species is one of the best cobalamin foods. About 6 oz (1/2 fillet) of fried salmon can provide 8.9 mcg (371% DV) of cobalamin.
Stewed wild coho salmon offers a slightly lower, but, objectively, still very high vitamin B12 content—6.94 mcg (289% DV) of cobalamin per 6 oz. On the other hand, fried farmed coho salmon provides 4.53 mcg (189% DV) per 5-oz fillet.
Besides being an excellent food with vitamin B12, coho salmon is high in protein, vitamin B6, and minerals like phosphorus, potassium, magnesium, and selenium.
Smoked sturgeon also boasts a high vitamin B12 content, providing 2.46 mcg (102% DV) of cobalamin per 3 oz.
Additionally, sturgeon is a very nutritious fish, particularly rich in vitamin D, vitamin A, phosphorus, and selenium.
A 3-oz serving of fried Alaska pollock offers 3.11 mcg (52% DV) of cobalamin, earning it a relatively high spot on the vitamin B12 foods list. A single fillet of this nutritious fish can provide you with as much as 2.2 mcg (37% DV).
Alaska pollock is also high in omega-3 fatty acids, calcium, and selenium.
Milk and dairy products are also excellent food sources of vitamin B12. It’s important to note that the fat content in milk slightly affects the cobalamin content.
High-fat milk (3.7%) provides 0.88 mcg (37% DV) per cup; whole milk (3.2%) provides 1.1 mcg (46% DV) per cup; low-fat milk (1%) offers 1.15 mcg (48% DV); and non-fat (skim) milk offers 1.23 mcg (51% DV).
Most importantly, milk and dairy products are some of the few natural dietary sources of B12 for vegetarians.
A cup of non-fat yogurt provides up to 1.5 mcg (63% DV) of vitamin B12, making it one of the valuable vitamin B12 foods.
Yogurt is also typically high in protein, calcium, and many other nutrients. Most importantly, this dairy product is one of the options of vitamin b12 foods for vegetarian diet followers.
A mere 3-oz serving of pan-fried lamb liver contains an astounding 72.8 mcg (3,033% DV) of vitamin B12, ranking it first on our vitamin B12 foods list. Braised lamb liver, on the other hand, provides 66.03 (2,751% DV) of cobalamin per serving.
The lamb liver is also high in protein, minerals (copper), and vitamins (A and B2).
Topping the list of foods rich in vitamin B12, a 3-oz serving of pan-fried liver offers a whopping 70.6 mcg (2,942% DV) of cobalamin. This means you can get as much as 67.3 mcg (2,804% DV) of vitamin B12 from a single slice weighing roughly 2.85 oz.
Besides being one of the highest-ranked foods with cobalamin, the beef liver also provides high amounts of protein, vitamin A, and minerals such as copper, iron, zinc, phosphorus, and selenium.
Grilled skirt steak is also one of the foods high in vitamin B12, with a 3-oz serving providing 6.4 mcg (267% DV) of vitamin B12.
Skirt steak also provides a fair amount of protein, phosphorus, selenium, iron, and zinc.
The amount of vitamin B12 in eggs depends chiefly on the cooking method. Namely, one cup of the chopped hard-boiled egg contains 1.51 mcg (63% DV) of vitamin B12. In other words, you can get 0.56 mcg (23% DV) from one large hard-boiled egg.
On the other hand, 7 oz of omelet, fried, or scrambled eggs contain 1.67 mcg (70% DV) of vitamin B12 or 0.45 mcg (19% DV) per egg.
It’s also important to note that eggs are a valuable B12 vegetarian source, besides dairy products.
Tempeh is a protein-rich soy-based food with relatively low vitamin B12 content in comparison with animal-based sources. It offers 0.1 mcg (3% DV) of cobalamin in 1/2 cup, making it one of the modest, but valuable plant-based vitamin b12 foods for vegan diet followers.
Nutritional yeast is also one of the few valuable vegan foods high in vitamin B12, with cobalamin content varying across different brands. In essence, a 1/4 cup of nutritional yeast can provide 8.3–24 mcg (346–1,000% DV) of vitamin B12.
Vitamin B12 Deficiency
Even a slight decrease in vitamin B12 levels can trigger deficiency symptoms. The most common causes of cobalamin deficiency include diseases characterized by cobalamin malabsorption, low stomach acid, and inadequate restrictive diet.
Gastrointestinal diseases such as gastritis, celiac disease, and inflammatory bowel disease can lead to vitamin B12 deficiency since they can interfere with cobalamin absorption.
Certain medications can also reduce vitamin B12 levels or impair its absorption. These include stomach-acid-reducing medication (esomeprazole, lansoprazole, cimetidine, famotidine, etc.), diabetes medication (metformin), cholesterol-lowering medication (colestipol, cholestyramine, etc.), gout medication (colchicine), chemotherapy medication (methotrexate), and anti-seizure medications (phenytoin, phenobarbital, and primidone).
Cobalamin deficiency can lead to severe and potentially permanent damage to the brain and the nervous system.
Some of the vitamin B12 deficiency symptoms include:
- Shortness of breath
- Weight loss
- Loss of appetite
- Tingling in the hands and feet
- Glossitis (sore tongue)
- Pale skin
- Palpitations (irregular heartbeat)
- Nerve damage (in severe cases)
It’s important to note that taking high doses (800 mcg) of folic acid can mask cobalamin deficiency symptoms. Due to the patient’s unawareness of deficiency, they may risk developing severe nerve damage and other complications.
People at Risk of Vitamin B12 Deficiency
A person’s susceptibility to vitamin B12 deficiency depends on three factors: age, diet, and health condition. The groups listed below are at risk of cobalamin deficiency the most:
- Vegans and vegetarians that don’t consume animal products like eggs and dairy—the primary natural source of vitamin B12
- Patients with nutrient absorption issues resulting from Crohn’s disease, weight loss surgery, medications, or pancreatic disease
- Individuals with Helicobacter pylori, the main culprit behind stomach ulcers (its presence negatively affects cells that produce gastric intrinsic factor necessary for proper vitamin B12 absorption)
- Eating disorder patients
- The elderly (since they’re more prone to having low gastric acid or diseases like atrophic gastritis that prevent vitamin B12 absorption)
- HIV patients
- Diabetic patients
About 10–30% of older people are likely to have problems absorbing vitamin B12. Many need to introduce more food containing vitamin B12 in their diets after the age of 50. Some even require supplementation.
Vitamin B12 Deficiency Treatment
The most common ways of combating vitamin B12 deficiency include:
- Foods high in cobalamin (lamb liver, clams, nutritional yeast, etc.)
- The use of high-dose oral vitamin B12 supplements
- Vitamin B12 injection
- Nasal vitamin B12 supplements (cyanocobalamin)
Research shows that vitamin B12 shots are the best vitamin B12 deficiency treatment for those with vitamin B12 malabsorption issues and severe deficiencies.
Health Benefits of Vitamin B12
Vitamin B12 is used for the prevention and treatment of several health conditions that are a direct consequence of cobalamin deficiency:
Pernicious anemia is a condition characterized by the stomach cells‘ inability to produce intrinsic factor, a substance critical for the body’s ability to absorb vitamin B12. The symptoms of this type of anemia are:
- Pale skin
- Weight loss
- Pins and needles
- Loss of balance
- Memory loss
Vitamin B12 is one of the three vitamins associated with preventing heart disease prevention (the other two being vitamin B6 and vitamin B9). Many studies highlight the link between high levels of homocysteine and heart disease.
Age-related macular degeneration is an eye disease that can potentially cause blindness. A study discovered that the risk of women developing AMD is significantly reduced by taking a combination of vitamin B12 supplement (1,000 mcg), folic acid (2,500 mcg), and vitamin B6 (500 mg) every day.
Fatigue is a common symptom of vitamin B12 deficiency, and it can be relieved by increasing vitamin B12 levels. A small-scale study indicates that even B12-non-deficient individuals might experience an energy boost upon taking a vitamin B12 shot.
Another study found that chronic fatigue syndrome patients could benefit from a vitamin B12 injection. However, more research is needed to verify these preliminary findings.
There’s no conclusive evidence that vitamin B12 can lower the risk of breast cancer. Still, certain population studies found that women with higher folate intake (a nutrient vitamin B12 works together with) are less likely to develop breast cancer.
Certain studies suggest that a good vitamin B12 supplement can increase sperm count and sperm motility. However, more research is required to corroborate these claims.
Vitamin B12 Side Effects
Taking oral vitamin B12 supplements like vitamin b12 tablets (even in high doses) doesn’t produce side effects in most healthy individuals. In rare cases, anaphylactic reactions such as tongue, throat, and face, accompanied by a difficulty in breathing and swallowing have been recorded.
These are the most common side effects of vitamin B12 injections:
- Mild diarrhea
- Skin rash
- Congestive heart failure and pulmonary edema (in the early treatment phases)
- Swelling sensation
- Vein thrombosis
- Polycythemia vera (a rare slow-growing cancer of the blood).
Vitamin B12 Recommended Daily Intake
The recommended dietary allowance depends on your age, condition, and activity levels. The following table outlines the recommended B12 vitamin dosage for different age groups:
|Infants (0–6 months)||0.4 mcg|
|Infants (7–12 months)||0.5 mcg|
|Toddlers (1–3 years)||0.9 mcg|
|Children (4–8 years)||1.2 mcg|
|Children (9–13 years)||1.8 mcg|
|Teens (14–18 years)||2.4 mcg|
|Adults (19+ years)||2.4 mcg|
These values should serve as general guidelines for vitamin B12 intake. However, it’s always best to consult a doctor about the adequate vitamin B12 supplementation dosage before self-medicating.
Vitamin B12 Overdose
It’s unlikely you’ll experience adverse side effects of too much vitamin B12 since the excess of this vitamin doesn’t accumulate in the body.
On the contrary, everything that isn’t used up is excreted through urine. Therefore, even an extremely high vitamin B12 dosage of 5,000 mcg is unlikely to be problematic. In other words, it’s virtually impossible for excessive supplementation or cobalamin-rich food intake to lead to vitamin B12 overdose.
This article covered various categories of vitamin B12 foods, deficiency symptoms, dosage, etc. Hopefully, it was detailed and insightful enough to equip you with sufficient knowledge about introducing the right cobalamin-rich foods to keep deficiency at bay.
What are the symptoms of B12 deficiency?
There are more than 10 different symptoms of vitamin B12 deficiency. They include fatigue, diarrhea, shortness of breath, paraesthesia, glossitis (sore tongue), irritability, behavioral changes, etc.
However, neither of these symptoms is a definitive indication of a deficiency, as other conditions can also trigger such symptoms.
How can I increase my B12 absorption?
You can increase your absorption of vitamin B12 by treating the underlying conditions that cause cobalamin malabsorption. You could also give up certain habits that disrupt vitamin B12 absorption, such as drinking alcohol.
What does a B12 shot do for you?
Vitamin B12 shots are most commonly used to prevent or treat vitamin B12 deficiency and deficiency-related diseases such as pernicious anemia. They’re prescribed exclusively by medical professionals to high-risk groups (malabsorption disease patients, vegans, the elderly, etc.).
How much does a B12 shot cost?
The cost of vitamin B12 shots depends on the source, place of administering, and insurance coverage. It may vary anywhere from $20 to over $100. If you self-administer the injection at home, the vitamin B12 injection may cost you from $27 to $30 if you opt for a kit that includes syringes and alcohol wipes.
What foods are high in B12 for vegetarians?
Unlike vegans who have a limited number of natural vitamin B12 food sources to choose from, vegetarians have more options since they don’t avoid all animal-sourced food.
Natural dietary sources of B12 for vegetarians include eggs, milk and dairy products, tempeh, fortified cereals, nutritional yeast, certain mushrooms (shiitake), yeast spreads, and algae.
Which foods are high in B12?
Foods with extremely high vitamin B12 content include lamb liver (3,033% DV per 3 oz), beef liver (2,942% DV per 3 oz), clams (1,426% DV per 3 oz), octopus (1, 275% DV per 3 oz), oysters (1,020% DV per 3 oz), nutritional yeast (up to 1,000% per 1/2 cup), etc.
How to get vitamin B12 naturally?
The only natural way to get vitamin B12 is through food. We’ve outlined over 20 vitamin B12 foods in this article, spanning across seafood (e.g., octopus, Dungeness crab, and wild coho salmon), dairy (e.g., milk and nonfat yogurt), plant-based (tempeh), and animal food sources (e.g., lamb liver and skirt steak).