Vitamin B12 (also known as cobalamin) is a water-soluble vitamin involved in the metabolism of every cell in the human body.
Vitamin B12 is the largest and most structurally complex vitamin. It is made almost exclusively by bacteria and found predominantly in animal foods.
This article will help you find foods and recipes that contain the most vitamin B12 using the tools and charts used by Optimisers in our Micros Masterclass.
- Vitamin B12 Food Chart
- Vitamin B12 Rich Foods (Per Serving)
- Vitamin B12 Rich Foods (Per Calorie)
- Vitamine B12 Rich Recipes
- Why is Vitamin B12 (Cobalamin) Important?
- Roles of Vitamin B12 in Your Body
- What Fruits and Vegetables Are High in B12?
- How Do Vegetarians Get B12?
- Symptoms of Vitamin B12 Deficiency
- Factors Increasing Your Risk of B12 Deficiency
- Satiety Response to Foods That Contain Vitamin B12
- Vitamin B12 Side Effects and Toxicity
- Optimal Vitamin B12 Intake
- Availability of Vitamin B12
- Synergistic Nutrients with Vitamin B12
- B12 Bioavailability
- Processing Losses
- Normal Ranges of B12 in the Blood
- How Can I Calculate if I am Getting Enough Vitamin B12?
- Nutrient Density Starter Pack
- Nutrient Series
Vitamin B12 Food Chart
The chart below shows a range of popular foods in terms of vitamin B12 (per calorie) vs vitamin B12 (per serve). Foods towards the right will provide more vitamin B12 per calorie, while the foods towards the top will provide more vitamin B12 in the serving sizes we typically eat them.
For more detail, you can dive into the interactive Tableau version of this chart (on your computer), check out the food lists of popular foods below or download longer lists in our Optimising Nutrition Community here.
Vitamin B12 Rich Foods (Per Serving)
The popular foods listed below will give you more vitamin B12 in the typical serving sizes we consume them in.
- ground beef
- beef steak
- chicken thigh
- chicken drumstick
- Swiss cheese
- egg (whole)
- Greek yogurt (non-fat)
- brie cheese
- pork chops
- Camembert cheese
Vitamin B12 Rich Foods (Per Calorie)
Foods highest in vitamin B12 per calorie tend to be green veggies like the ones listed below.
- Greek yogurt (non-fat)
- beef steak
- ground beef
- chicken drumstick
- chicken thigh
- chicken drumstick
- Swiss cheese
- milk (whole)
- egg (whole)
- feta cheese
Vitamine B12 Rich Recipes
The chart below shows our 1400+ NutriBooster recipes that we use in the Micros Masterclass plotted in terms of vitamin B12 vs protein %. Recipes towards the right will help you boost your vitamin B12 with fewer calories.
Vitamin B12 tends to be correlated with protein %, so if you’re getting plenty of protein from an omnivorous diet, you should be getting plenty of vitamin B12.
To dive into the detail, you can open the interactive Tableau version of this chart (on your computer). Then, click on each recipe to learn more about it and view a picture of the recipe.
A selection of NutriBooster recipes that contain the most vitamin B12 is shown below.
Why is Vitamin B12 (Cobalamin) Important?
- DNA synthesis: Vitamin B12 plays a crucial role in the synthesis of DNA, the body’s genetic material. It helps in the formation of red blood cells and the development and maintenance of the nervous system.
- Red blood cell formation: Vitamin B12 is required to properly form red blood cells, which carry oxygen to the body’s tissues. A deficiency in vitamin B12 can lead to a type of anemia called megaloblastic anemia.
- Nervous system function: Vitamin B12 is necessary for the proper functioning of the nervous system. It helps form myelin, a fatty substance that covers and protects nerve fibres and helps transmit nerve impulses.
- Energy production: Vitamin B12 is involved in metabolising carbohydrates, proteins, and fats and helps produce energy from food.
- Cognitive function: Vitamin B12 is essential for cognitive function, including memory, concentration, and mood regulation.
- Fetal development: Vitamin B12 is important for fetal development during pregnancy, particularly for brain and nervous systems.
Roles of Vitamin B12 in Your Body
- Vitamin B12 is critical for many reactions and crucial for synthesising healthy blood cells and preventing anemia.
- Cognition and neurological function rely heavily on vitamin B12, and its deficiency has been linked to issues with memory and thought processes. B12 has also been shown to prevent the loss of neurons.
- Our mitochondria need vitamin B12 to make energy.
- B12 is one of the most fundamental vitamins for the process of methylation. Methylation helps produce neurotransmitters important for a happy mood, detoxify the body, and initiate metabolism.
- The health of the cardiovascular system depends on vitamin B12 to keep inflammatory homocysteine levels in balance.
- Adequate B12 is vital for skin health, and deficiency has been linked to nail discolouration, hyperpigmentation, vitiligo, and acne.
- B12 is needed to protect the fetal brain and nervous system, ensure proper development, and prevent congenital disabilities like neural tube defects.
- Sufficient amounts of B12 have been linked to better bone density, meaning vitamin B12 is vital for the skeletal system.
- Vitamin B12 is required in conjunction with folate for DNA synthesis. We also need vitamin B12 to absorb folate well.
What Plant Foods are High in B12?
Because bacteria exclusively produce B12, it is almost solely found in animal foods. This is because the bacteria in the animal’s intestines synthesise B12, which the animal then absorbs.
Unfortunately, humans do not operate like animals and must rely on varying animal foods for B12. Meat, poultry, eggs, seafood, and dairy foods are inherently great sources of B12. Vegetarians can meet their minimum daily B12 requirement with four large eggs.
What Fruits and Vegetables Are High in B12?
Given that B12 is either present in animal tissues or produced by bacteria, there is no fruit or vegetable source of vitamin B12 for humans. In addition, while algae contain B12, it is not usable for humans and is, therefore, not considered a B12 food.
How Do Vegetarians Get B12?
Because there are no common vegetable sources, strict vegans must supplement, consume fortified foods, or receive regular Vitamin B12 injections to avoid serious health consequences.
Vegan foods containing B12 are few and far between. Food sources like nutritional yeast can supply some B12, but it might not be a reliable source. For this reason, it is highly recommended to supplement to avoid deficiency.
If you’re a vegetarian, it’s a little easier to get your B12 from food because there are ample amounts of vitamin B12 in dairy.
Symptoms of Vitamin B12 Deficiency
Lower intakes of vitamin B12 are associated with a wide range of conditions, including:
- congenital disabilities,
- macular degeneration,
- cognitive impairment,
- pins and needles (paresthesia),
- a sore and red tongue (glossitis),
- mouth ulcers,
- extreme fatigue,
- memory loss, and
- low energy levels.
Although vitamin B12 is a water-soluble vitamin, it can be stored in the body for up to four years. This can be bittersweet because a deficiency might not be diagnosed or documented until someone is ‘in too deep’, and the symptoms of B12 deficiency may take some time to reverse.
Because deficiency symptoms of vitamin B12 and folate are so similar, it’s essential to ensure you’re consuming enough of both nutrients if you’re experiencing any of the symptoms discussed above.
Factors Increasing Your Risk of B12 Deficiency
The absorption of vitamin B12 mainly depends on the functioning of the gastrointestinal system. First, stomach acid separates B12 from the protein it’s attached to. It is then combined with a protein known as ‘intrinsic factor’ where it is absorbed.
If digestion is subpar or impaired, this process doesn’t happen effectively, and someone could be at risk for B12 deficiency even if they’re consuming enough B12.
Conditions like pernicious anemia result from what is thought to be an autoimmune reaction against parietal cells that create intrinsic factor. In this case, someone will need to take supplemental B12 for the rest of their life.
You may be at risk of B12 deficiency if you:
- are older,
- have poor digestion,
- have pernicious anemia,
- have or had an infection of the GI tract,
- suffer from IBS or IBD,
- have had bariatric surgery,
- follow a strict vegan diet,
- overconsuming folate (often from supplements),
- take H2 antihistamines,
- take metformin for blood sugar control, or
- take proton pump inhibitors for heartburn.
Satiety Response to Foods That Contain Vitamin B12
Our satiety analysis suggests that we have a strong satiety response to foods containing up to around 20 mcg of B12 per 2000 calories.
This amount of B12 is significantly more than the Estimated Average Requirement for vitamin B12 of 2.0 mcg/day and the Daily Reference Intake for vitamin B12 of 2.4 mcg/day. For reference, the median B12 intake of our Optimisers is 10 mcg/2000.
Vitamin B12 Side Effects and Toxicity
Because vitamin B12 is a water-soluble vitamin, no toxic or adverse effects have been associated with large intakes of vitamin B12 from food or supplements in healthy people.
Supplemental doses as high as 2 mg daily by mouth or 1 mg monthly by injection have been used without significant side effects. Because of the low toxicity of vitamin B12, no tolerable upper intake level has been set for this nutrient.
It is important to note that vitamin B12 is an antagonist of B1, and the use of B12 increases the demand for folate. With that being said, it’s essential to consume enough of both B1 and folate if you’re on a plant-based diet and supplementing with high amounts of B12 to avoid deficiencies elsewhere.
Optimal Vitamin B12 Intake
Based on the robust satiety response data, we have set a stretch target of 12 mg/2000 calories for vitamin B12.
Once you start to get the hang of nutrient density, you could ‘level up’ by working to achieve these stretch targets to optimise your nutrition. For more details, see:
Availability of Vitamin B12
Although we began synthesising B12 in 1970 and now use it to fortify foods, the availability of Vitamin B12 in the food system has decreased substantially since the 1977 US Dietary Guidelines, as shown in the chart below (produced using data from the USDA Economic Research Service). As a result, vitamin B12 is a nutrient you may need to pay more attention to ensure you obtain adequate amounts for optimal health.
Interestingly, the decrease in vitamin B12 in the food system has correlated strongly with increased obesity rates.
Synergistic Nutrients with Vitamin B12
Vitamin B12 works synergistically with vitamins A, B1, B2, B5, B6, C, E, biotin, calcium, cobalt, copper, folate, iron, methionine, omega-3 fatty acids, phosphate, and selenium.
These are the nutrients that the body needs alongside B12 to execute its involved functions. For this reason, it is best to consume vitamin B12 from food with the entire spectrum of these nutrients.
The bioavailability of vitamin B12 decreases significantly with an increased intake of vitamin B12. Therefore, although it may seem like a paradox, your body needs to absorb less B12 as it refills its stores as you begin to consume more foods containing this nutrient.
As you can’t stock up on vitamin B12 because it is water-soluble and not stored in fat, you need to consume foods that contain it regularly.
The bioavailability of vitamin B12 from animal products ranges from 42 to 66%. Interestingly, vitamin B12 in eggs seems to be poorly absorbed in amounts less than 9%.
The official Dietary Reference Intake is based on the assumption that healthy adults with normal gastrointestinal function absorb 50% of their dietary vitamin B12.
Some plant foods, such as seaweed, contain substantial amounts of vitamin B12. However, the edible blue-green algae (cyanobacteria) used for human supplements predominantly contain pseudo vitamin B12, which is inactive in humans.
The bacteria residing in the human gut produce B12. However, it is made in the lower intestine, where it cannot be absorbed for use in our body.
B12 has been measured in some plant-based foods. However, this is typically due to using “night soil” or human faeces to fertilise gardens. As a result, the B12-producing bacteria from their stools are consumed with the plants. As you can imagine, this can have more negative health implications than benefits.
Vitamin B12 is unstable in the presence of heat, light, acid, and alkali. Losses in food range from 10 to 90% from these factors, which does not consider the loss of B12 during absorption. Hence, it is important to consume fresh foods regularly to optimise their B12 contents.
Normal Ranges of B12 in the Blood
The normal range for vitamin B12 in the blood is between 200 and 900 nanograms per millilitre (ng/mL). People at the lower end of this range may require follow-up testing, especially if they are experiencing any of the symptoms listed above.
Levels of vitamin B12 are considered low if they are below 200 ng/mL. This suggests a vitamin B12 deficiency, pernicious anemia, or an overactive thyroid.
Those with deficient Vitamin B12 levels often experience neurological symptoms and fatigue.
An abnormally high vitamin B12 status is anything over 900 ng/mL. This result indicates that your body cannot clear B12 effectively and may suggest liver or kidney problems, issues with methylation, diabetes, or certain forms of leukemia.
How Can I Calculate if I am Getting Enough Vitamin B12?
If you’re interested in determining if you’re getting the right amount of vitamin B12 in your diet, you can check your nutrient profile using our Free 7-Day Nutrient Clarity Challenge.
After a week of tracking your current diet in Cronometer, Nutrient Optimiser will give you a prioritised list of foods and NutriBooster recipes that will help you plug your current nutritional gaps, including selenium.
Nutrient Density Starter Pack
We’re eager to make the process of Nutritional Optimisation as simple as possible. So, to help you increase your intake of all the essential nutrients, including vitamin B12, when you join our free Optimising Nutrition Community, you’ll get a starter pack that includes:
- Food Lists – optimised for each essential nutrient, goals, preferences and conditions.
- The Healthiest Meal Plan in the World – see what a week of nutrient-dense eating looks like.
- Recipes – check out samples of each of our NutriBosoter recipe books.
- 7-Day Nutrient Clarity Challenge – identify your priority nutrients and the foods and meals that contain them.
- Biotin (B7)
- Vitamin A
- Vitamin E
- Thiamine (B1)
- Riboflavin (B2)
- Niacin (B3)
- Pantothenic acid (B5)
- Vitamin B6
- Folate (B9)
- Vitamin B12
- Vitamin C
- Vitamin D
- Vitamin K1
- Vitamin K2