Cobalamin (B12) in Focus – FooDosage Nutrition Calculator
Vitamin B12 (due to its cobalt containing nature also known as cobalamin, or the supplemental synthetic forms hydroxocobalamin, methylcobalamin, or cyanocobalamin) is a water-soluble vitamin in the B series, and as such, is needed for energy metabolism and plays a role in protein and fat metabolism, as well as maintaining the functionality of the nervous system.
B vitamins are also needed to maintain a healthy liver, healthy skin, hair, and eyes, as well as normal embryonic growth. Vitamin B12 specifically is essential for proper red blood cell formation (in conjunction with B9), neurological function, and DNA synthesis.
Neither humans, nor other animals, nor plants, nor mushrooms are able to produce cobalamin. Only certain bacteria possess that capability. The substance moves up in the food chain (and is produced by bacteria in the guts of ruminants such as cows and sheep), and accumulates in muscle and organ tissue, but is not absorbed by plants. As such, we can only get B12 from animal sources. Vegetarians, Vegans, and people who do not consume animal products often and regularly must take supplements or eat fortified foods to reach their minimum intakes and stave off a deficiency.
Being water-soluble, it is stored in the liver and heart in small quantities, but excess amounts will be expelled quickly. This means we need an adequate, ongoing (daily) supply to keep B12 levels in the optimal range.
This article will cover the recommended intake levels, why we want to reach those levels, the dangers of overconsumption, and which foods are richest in Cobalamin. As a twist, we sort foods by their nutrient to calorie ratios, as opposed to the more common per 100 gram values. This is because per calorie values correct for water content, and satiation, but more on that later.
Note that all recommended intake figures below are based on the needs of a 31 year old non-pregnant, non-lactating woman on a 2000 kilocalorie diet. Your personal requirements may differ (wildly). One way to figure out your individual needs, including calories per day, is the FooDosage Nutrition Calculator. It’s free, by the way.
Recommended Cobalamin Intake
The recommended intake range for Vitamin B12, as set by the National Academy of Sciences:
Recommended minimum intake (RDA): 2.4 µg per day
Upper limit: –
Note that your personal requirements may differ depending on your age, sex, pregnancy-, and lactation status.
Special Considerations
- Because 10 to 30 percent of older people may malabsorb foodbound vitamin B12, it is advisable for those older than 50 years to meet their RDA mainly by consuming foods fortified with vitamin B12 or a supplement containing vitamin B12.
- Because there are no vegan sources of Vitamin B12, people living on vegan diets and most people living on vegetarian diets need to meet their RDA with the help of fortified foods, or supplements.
Importance of an Adequate Cobalamin Intake (Dangers of a Deficiency)
A Vitamin B12 deficiency can cause severe and irreparable damage to the brain and nervous system. Symptoms include:
- Megaloblastic anemia
- Neurological changes, such as numbness and tingling in the hands and feet (can be irreversible if not treated in time)
- Fatigue
- Lethargy
- Depression
- Poor memory
- Breathlessness
- Headaches
- Pale skin
- Constipation
- Loss of appetite
Risks of an Excessive Cobalamin Consumption (Side Effects)
As a water-soluble vitamin, excess B12 is usually expelled without complication. As opposed to fat soluble vitamins, liver toxicity is not a big danger.
There is no evidence of adverse effects from the consumption of naturally occurring Vitamin B12 in foods or the synthetic forms in supplements. Though data is limited, so caution may be warranted.
Top 12 B12 Food Sources
The highest concentrations of Vitamin B12 are usually found in organ meats such as livers or kidneys (especially beef and sheep), fish, mollusks, crustaceans, and meats, again especially from ruminants such as cows and sheep.
Some choice examples of Cobalamin rich foods:
Note that for this ranking, the foods were sorted by their nutrient/calorie contents, as opposed to the more common nutrient/gram sorting method. This is because per calorie values correct for water content, and satiation. Example: Butter may contain more Vitamin A than Spinach per 100 grams, but eating the 120 grams of spinach necessary to reach the minimum recommended amount of Vitamin A is by far more feasible (and recommendable) than to eat the 100 grams of butter required for the same amount of Vitamin A.
Cobalamin (B12) Leaderboard – FooDosage Nutrition Calculator
Beef Liver (New Zealand)
Cobalamin (B12) per 100g (boiled): 96 µg (4000% of recommended minimum intake.)
Cobalamin (B12) per 100 kcal: 64 µg (Corrects for water content and satiation.)
Beef Liver with Sage
Calories per 100g: 150 kcal
As is the case for many nutrients, livers in general are extremely dense in Folate, cow and sheep livers especially, and New Zealand beef livers take the crown. It’s not the worst idea to incorporate a bit of liver into your diet, but beware:
Apart from B12 and many other nutrients, liver is so rich in vitamin A and manganese, that you should only eat small amounts to not exceed the upper limit. Since vitamin A is fat soluble, this can be taken as a weekly average.
But Vitamin A and manganese are not the only reason to limit liver consumption to very small amounts. Heavy metals such as arsenic, cadmium and lead, as well as pesticides tend to collect in farm animals’ livers. Try to only buy organic meat to get “cleaner” livers, apart from all the other arguments for buying organic foods in general.
Beef liver is also a fantastic source of:
- Vitamin A – at 21014 µg / 100g (3002% of RMI. WARNING: The upper limit is 3000 µg.)
- Manganese – at 328 mg / 100g (18’222% of RMI. WARNING: The upper limit is 11 mg.)
- Copper– at 5.73 mg / 100g (637% of RMI)
- Riboflavin (B2) – at 3.04 mg / 100g (276% of RMI)
- Pantothenic acid (B5) – at 9.8 mg / 100g (196% of RMI)
Oysters
Cobalamin (B12) per 100g (cooked, dry heat): 24.3 µg (1013% of recommended minimum intake.)
Cobalamin (B12) per 100 kcal: 30.8 µg (Corrects for water content and satiation.)
Oysters
Calories per 100g: 79 kcal
Though their supposed potency as an aphrodisiac is up for debate, and their taste and texture isn’t everybody’s cup of tea, what’s unquestionable is how rich in B12 and many other nutrients oysters are. Just ten grams will suffice to reach your daily minimum.
Of course, it doesn’t have to be oysters. Other mussels and mollusks in general also have good or great amounts of Colobalamin, oysters just lead the pack in per calorie rankings (followed by blue mussels).
Please buy only MSC (wild caught), organic (farmed), or at least ASC (farmed) certified fish and seafood
Oysters are also an excellent source of:
- Zinc – at 45.15 mg / 100g (564% of RMI. ATTENTION: The upper limit is 40 mg.)
- EPA & DHA N-3 (Omega 3) Fatty Acids – at 0.44 g / 100g (176% of RMI)
- Copper – at 1.43 mg / 100g (159% of RMI)
- Selenium – at 77.5 µg / 100g (141% of RMI)
- Iron – at 7.77 mg / 100g (43% of RMI)
Example: Crown Prince Natural Smoked Oysters in Pure Olive Oil (Amazon)
Octopus
Cobalamin (B12) per 100g (cooked, moist heat): 36 µg (1500% of recommended minimum intake.)
Cobalamin (B12) per 100 kcal: 22 µg (Corrects for water content and satiation.)
Octopus
Calories per 100g: 164 kcal
Like oysters, octopus can be an acquired taste for many people. Also like oysters, the slightly gummy textured and sucker filled, but delicious arms are a fantastic source of Vitamin B12.
Please buy only MSC (wild caught), organic (farmed), or at least ASC (farmed) certified fish and seafood
Octopus is also an excellent source of:
- Selenium – at 89.6 µg / 100g (163% of RMI)
- EPA & DHA N-3 (Omega 3) Fatty Acids – at 0.31 g / 100g (126% of RMI)
- Copper – at 0.74 mg / 100g (82% of RMI)
- Protein – at 29.8 g / 100 g (61% of RMI)
- Iron – at 9.54 mg / 100g (53% of RMI)
Mackerel
Cobalamin (B12) per 100g (cooked, dry heat): 18 µg (750% of recommended minimum intake.)
Cobalamin (B12) per 100 kcal: 13.4 µg (Corrects for water content and satiation.)
Baked Mackerel
Calories per 100g: 134 kcal
Mackerel is one of the most nutritionally valuable fish in many respects, among them Vitamin B12. Many people think of a very fishy, even rancid taste when they think of mackerel (which some like, of course), but that should mainly be the case if the fish wasn’t very fresh (or if it was smoked). Telltale signs are matted skin, dry-looking flesh, or a darker than off-white color. Fresh, mackerel tastes similar to salmon.
Please buy only MSC (wild caught), organic (farmed), or at least ASC (farmed) certified fish and seafood
Mackerel is also an excellent source of:
- EPA & DHA N-3 (Omega 3) Fatty Acids – at 0.40 g / 100g (160% of RMI)
- Selenium – at 46.8 µg / 100g (85% of RMI)
- Niacin (B3) – at 10.5 mg / 100g (75% of RMI)
- Riboflavin (B2) – at 0.58 mg / 100g (53% of RMI)
- Protein – at 26 g / 100 g (53% of RMI)
Example: Ruegen Mackerel Fillets in Tomato Sauce (Amazon)
King Crab (Alaska)
Cobalamin (B12) per 100g (cooked, moist heat): 11.5 µg (479% of recommended minimum intake.)
Cobalamin (B12) per 100 kcal: 11.9 µg (Corrects for water content and satiation.)
Crab Legs
Calories per 100g: 97 kcal
Today is a good day for seafood lovers. Apart from mollusks and fish, crustaceans also make for a very good source of B12. First among them is the Alaska king crab. A measly 25 grams of its meat will already put you over your daily minimum, but who could stop after just 25 grams? Dig in, those crab legs are not only delicious but rich in many nutrients.
Please buy only MSC (wild caught), organic (farmed), or at least ASC (farmed) certified fish and seafood
King Crab is also an excellent source of:
- EPA & DHA N-3 (Omega 3) Fatty Acids – at 0.41 g / 100g (165% of RMI)
- Copper – at 1.18 mg / 100g (131% of RMI)
- Zinc – at 7.6 mg / 100g (95% of RMI.)
- Selenium – at 40 µg / 100g (73% of RMI)
Emu (Fan Fillet)
Cobalamin (B12) per 100g (broiled): 9.37 µg (390% of recommended minimum intake.)
Cobalamin (B12) per 100 kcal: 6.08 µg (Corrects for water content and satiation.)
Calories per 100g: 154 kcal
Ah, those Emus again. They provide one of the healthiest, most ecological and delicious red meats you can get. If only it was more commonly available. If you can get your hands on some, dig in!
Emu fan fillet is also a great source of:
- Selenium – at 46.1 µg / 100g (84% of RMI)
- Niacin (B3) – at 9.81 mg / 100g (70% of RMI)
- Vitamin B6 – at 0.92 mg / 100g (70% of RMI)
- Pantothenic Acid (B5) – at 3.39 mg / 100g (68% of RMI)
- Protein – at 31.3 g / 100 g (64% of RMI. Completeness: 95%, deficient in Tryptophan)
Moose
Cobalamin (B12) per 100g (roasted): 6.31 µg (263% of recommended minimum intake.)
Cobalamin (B12) per 100 kcal: 4.7 µg (Corrects for water content and satiation.)
Calories per 100g: 134 kcal
Also not exactly widely available in most places, but delicious and rich in Cobalamin: Moose. If you can’t or won’t buy any, game meat in general makes for a good alternative.
Moose is also a great source of:
- Protein – at 29.3 g / 100 g (60% of RMI)
- Zinc – at 3.68 mg / 100g (46% of RMI.)
- Niacin (B3) – at 5.26 mg / 100g (38% of RMI)
- Riboflavin (B2) – at 0.34 mg / 100g (31% of RMI)
- Vitamin B6 – at 0.37 mg / 100g (28% of RMI)
Beef (Chuck Steak)
Cobalamin (B12) per 100g (lean only, grilled): 5.71 µg (238% of recommended minimum intake.)
Cobalamin (B12) per 100 kcal: 3.24 µg (Corrects for water content and satiation.)
Beef Steak
Calories per 100g: 176 kcal
And finally we have arrived at the classic, beef. A lean chuck steak is the most Cobalamin-dense cut, but the differences between cuts are not all that big. You will also get your fill of B12 from fillets, entrecôtes, sirloin steaks, or basically any other part of the cow. The leaner, the denser.
Please buy only organic, or at least grass fed beef.
Beef chuck steak is also a great source of:
- Zinc – at 7.58 mg / 100g (95% of RMI.)
- Selenium – at 44.3 µg / 100g (81% of RMI)
- Protein – at 26.7 g / 100 g (55% of RMI. Completeness: 92%, deficient in Tryptophan)
- Vitamin B6 – at 0.59 mg / 100g (46% of RMI)
- Niacin (B3) – at 5.49 mg / 100g (39% of RMI)
Lamb (Shoulder)
Cobalamin (B12) per 100g (broiled): 3.11 µg (130% of recommended minimum intake.)
Cobalamin (B12) per 100 kcal: 1.48 µg (Corrects for water content and satiation.)
Calories per 100g: 210 kcal
A good alternative to beef, or just for variety, lamb shoulder may not carry as much B12, but a hundred grams will still get you over the minimum.
Please buy only organic, or at least grass fed meat.
Lamb shoulder is also a great source of:
- Zinc – at 6.6 mg / 100g (83% of RMI.)
- Selenium – at 31.3 µg / 100g (57% of RMI)
- Protein – at 27.1 g / 100 g (56% of RMI.)
- Niacin (B3) – at 6.15 mg / 100g (44% of RMI)
- Phosphorus – at 217 mg / 100g (31% of RMI)
Cheese (Swiss)
Cobalamin (B12) per 100g: 3.06 µg (128% of recommended minimum intake.)
Cobalamin (B12) per 100 kcal: 0.779 µg (Corrects for water content and satiation.)
Swiss Cheese
Calories per 100g: 393 kcal
Swiss cheese, or dairy products in general, represents our first vegetarian option, as cows pass on some B12 through their milk.
Swiss cheese is also a good source of:
- Calcium – at 890 mg / 100g (89% of RMI)
- Phosphorus – at 574 mg / 100g (82% of RMI)
- Zinc – at 4.37 mg / 100g (55% of RMI.)
- Selenium – at 30 µg / 100g (55% of RMI)
- Vitamin A – at 288 µg / 100g (41% of RMI)
Example: Emmentaler Cheese AOC (Amazon)
Greek Yogurt
Cobalamin (B12) per 100g: 0.75 µg (31% of recommended minimum intake.)
Cobalamin (B12) per 100 kcal: 0.77 µg (Corrects for water content and satiation.)
Calories per 100g: 97 kcal
When comparing by calories just as good an option as cheese, greek yogurt is a health nut favorite. Though due to it nutrient profile, it will probably never feature in our leading the charts category, it is quite tasty.
Greek yogurt is also a good source of:
- Riboflavin (B2) – at 0.28 mg / 100g (25% of RMI)
- Protein – at 9 g / 100 g (18% of RMI.)
- Phosphorus – at 135 mg / 100g (19% of RMI)
- Selenium – at 9.7 µg / 100g (18% of RMI)
Eggs
Cobalamin (B12) per 100g (boiled): 1.11 µg (46% of recommended minimum intake.)
Cobalamin (B12) per 100 kcal: 0.72 µg (Corrects for water content and satiation.)
Eggs
Calories per 100g: 155 kcal
And for our final vegetarian option, we have eggs. They may not have the highest B12 contents, but that’s not the main reason we want them in our diets anyway. Mainly, they’re delicious and very nutritious in a diverse way, which shouldn’t come as a surprise considering they store all the nutrients for a growing life.
Boiled eggs are also a great source of:
- Choline – at 294 mg / 100g (69% of RMI)
- Selenium – at 30.8 µg / 100g (56% of RMI)
- Pantothenic Acid (B5) – at 1.4 mg / 100g (28% of RMI)
- Phosphorus – at 172 mg / 100g (25% of RMI)
- Vitamin A – at 149 µg / 100g (21% of RMI)
Bonus “per 100 grams” leader: New Zealand Beef Liver
Ooops, we already had that. I like to include the per 100 grams leader for comparison purposes, but in the case of Cobalamin, beef liver is also the top per 100 calorie leader, which you could say confirms it as a great choice. In general, the two rankings look very similar this time.
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Bon Appetit 🙂
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