Vitamin B12 in Foods

Foods which are good sources of B12

Vitamin B12, also known as cobalamin along with a variety of other names, is the largest and most complex vitamin currently known to man. This page contains a wealth of information on this essential nutrient, including a vitamin B12 foods list that highlights the basic everyday foods that contain this important vitamin, and a chart showing your recommended daily intake.

Here on this page we not only answer the question ‘what is vitamin B12?’ but also include sections covering  B12 sources, dosage and side effects. When it comes to this important vitamin, this really is your ‘all you need to know’ source!

What is vitamin B12?

Vitamin B12, or ‘the energy vitamin’ as it is often called, is a member of the family of vitamins known as the ‘B-complex’ family.

It is a water soluble vitamin that is manufactured by bacteria and can only be found naturally in animal products. However, synthetic forms are readily available and added to foods like cereals, which is good news for vegans and those on restricted diets. Excess B12 can be excreted from the body if it has been consumed in large doses, however it it can be stored in the liver for up to a year. This vitamin is therefore unusual because it is possible to take supplements on a weekly basis rather than every day as with most vitamins and minerals.

RDI Vitamin B12

  • 2.4µg Adults
  • 2.6µg Pregnant women
  • 2.8µg Breastfeeding women
  • 2.4µg Children 14-18 years
  • 1.8µg Children 9-13 years
  • 1.2µg Children 4-8 years
  • 0.9µg Toddler 1-3 years
  • 0.5µg Infants 7-12 months
  • 0.4µg Infants 0-6 months

As vitamin B12 can be produced synthetically, you may find it referred to under a variety of different names, including:

  • Aquocobalamin
  • Cobrynamide
  • Cobinamide
  • Cobamide
  • Cobalamin
  • Cyanocobalamin
  • Hydroxocobalamin
  • Methylcobalamin
  • Nitrotocobalamin

You will notice that these names all include part of the word ‘cobalt’ in them, because the mineral cobalt is found at the centre of this vitamin.  This is known as an organometallic compound and B12 is the only essential nutrient to have this structure. The different names refer to the chemical structure of the various forms of this vitamin, and need not concern us here. However, if you have a deficiency you may have to take supplements, so in this case you can look out for any of these names and be reassured that they all refer to vitamin B12.

List of Vitamin B12 Rich Foods

Foods which contain B12

Now we have come to our vitamin B12 foods list that will show you the best things to eat in order to make sure that you are getting enough of this essential nutrient. As you will see from the below list of B12 foods, this nutrient naturally occurs mostly in fish, meats and dairy products. Therefore as we have already said, if you are vegetarian or vegan it’s a good idea to include some fortified cereals in your diet.

The Best Vitamin B12 Foods

All amounts are in micrograms (μg) per 100 g (3.5 oz).


  • Clams, cooked – 98.8 μg
  • Crab – 11.5 μg
  • Haddock – 2.1 μg
  • Halibut – 1.3 μg
  • Herring – 13.1 μg
  • Kippers – 18.7 μg
  • Lobster – 4.0 μg
  • Mackerel – 19.0 μg
  • Mussels – 24.0 μg
  • Oysters, fried 15.6 – μg
  • Salmon- 5.8 μg
  • Sardines, canned in tomato sauce – 9.0 μg
  • Scallops – 2.2 μg
  • Snapper- 3.4 μg
  • Trout – 6.3 μg
  • Tuna – 10.9 μg

Fortified breakfast cereals

  • All bran original – 18.8 μg
  • Corn flakes – 9.5 μg
  • Multigrain cheerios – 20.7 μg
  • Kelloggs Special K – 19.5 μg

Eggs and Dairy products

  • Cheese, camembert – 1.3 μg
  • Milk, skimmed – 0.5 μg
  • Cheese, parmesan – 2.3 μg
  • Chicken eggs- 2.0 μg
  • Cheese, feta – 1.7 μg
  • Milk. powdered – 3.2 μg
  • Cheese, swiss – 3.3 μg
  • Goose eggs – 5.1 μg
  • Duck eggs 5.4 μg


  • Beef – 6.0 μg
  • Beef liver – 83.1 μg
  • Lamb, shoulder – 3.3 μg
  • Lamb liver – 85 μg
  • Liver sausage – 13.5 μg
  • Venison – 3.6 μg

Other sources


  • Rice milk – 0.6 μg
  • Yeast extract (marmite) – 15 μg

Vitamin B12 Benefits

Supplements, dosage and side effects

What does B12 do?

Needed for a healthy nervous system (your nerves, brain and spinal cord), it aids the metabolism of fats, proteins and carbohydrates, helping to turn food into energy. It also helps in the formation of red blood cells and helps your body to use iron and folic acid as efficiently as possible.

There is another way to get a regular amount of this vitamin inside your body and this is through vitamin B12 shots. Some people are unable to absorb this vitamin into their blood stream through vitamin B12 foods, and if your doctor has advised that you are one of these people, then it can be easier to just take a shot straight into the blood stream. This may sound unusual but some people can see this as a regular energy boost! For more information on vitamin B12 shots and other sources of  B12 such as supplements please speak to your doctor or other medical professional.

Vitamin B12 dosage

The recommended daily intake (RDI) of vitamin B12 varies in different countries. While the dosage in our list to the top right of the page states that adults need 2.4 micrograms the recommended level in the UK is 1.5 μg and in Europe is just 1.0 μg! So you can see it’s not difficult to get enough of this nutrient if you are eating items from our vitamin B12 foods list. However as it can be stored in the body for years and excess amounts are excreted, we would recommend following the higher RDI to be sure you don’t risk suffering from a vitamin B12 deficiency.

As we have already mentioned, vegans should get this vitamin through fortified foods or supplements, as plant sources don’t provide this vitamin naturally. Many people over the age of 50 should also use B12 supplements or eat fortified foods, as older adults are less able to absorb this vitamin from foods.

Vitamin B12 Side Effects

So we have covered benefits and sources in our vitamin B12 foods list, but how about side effects? With many nutrients there is a risk of damage if you consume too much but with B12 there is no chance of this as anything that the body does not need or use will just be passed out as urine.

However, for the  minority there are possible side effects and these can include:

  • Allergic reactions
  • Insomnia
  • Skin irritation and itching
  • Anxiety
  • Heartburn
  • Mild diarrhoea

Taking this vitamin should be avoided altogether if:

  • You suffer from Leber’s disease
  • You have any kind of allergy or sensitivity to cobalt or forms of cobalt

If you are unsure about anything when it comes to how much vitamin B12 you should be consuming per day or whether it is safe or not for you to take supplements, you should consult your doctor or a medical professional immediately.

Vitamin B12 Deficiency Symptoms

While this vitamin can be stored in the liver for a year or more, if you do not consume sufficient amounts over a long period of time you will develop a deficiency. Symptoms of slight deficiency include anaemia, fatigue, depression and heart palpitations, whereas a severe deficiency can cause permanent damage to the brain and central nervous system. For a much more detailed explanation that also covers both the causes and treatment of  this, please see our page dedicated to vitamin B12 deficiency symptoms. However if you are concerned, you should speak to a medical practitioner as soon as possible.  The sooner that this problem is addressed the less chance there is of any long term damage being done.