What is Vitamin B12 and where do I get it?

With New Year’s resolutions in their peak and the plant-based movement in full swing, it’s more important than ever to recognize which particular nutrients need a little extra attention if you are cutting out or cutting down on meat and / or animal products. One of these all-important nutrients is Vitamin B12.

Here’s a little about Vitamin B12

Vitamin B12 is a water-soluble vitamin, meaning once consumed it’s carried to the body’s tissues but not stored in the body.

It’s naturally present in some foods, added to others, and available as a dietary supplement as well as a prescription medication.

It plays a variety of roles in the body including:

  • Metabolizing food and producing energy
  • Producing red blood cells
  • Creating DNA
  • Maintaining a healthy nervous system.
  • It also plays a role (along with other nutrients) in keeping levels of a compound in the blood called ‘homocysteine’ low; if homocysteine levels are too high, your risk of cardiovascular conditions and dementia may be increased.

Without sufficient B12 we may develop intense fatigue, anemia, decreased ability to think, or depression. Though deficiency for those starting out with adequate stores may take years to develop, it can occur. In extreme cases B12 deficiency can be devastating, with cases reported of paralysis, psychosis, blindness, and even death.

But the good news is that B12 deficiency is easy to prevent!

Where do I get B12?

Human bodies cannot produce vitamin B12, we must obtain it from our diet. I often hear that “the fact that a vegan diet does not naturally contain B12 is proof that it is not a natural way to for humans to eat”… But B12 is actually produced by microorganisms. While meat is a good source of B12, those animals don’t produce the B12 themselves. It is produced by bacteria and gets stored in animal tissues as they eat unwashed food that get pretty dirty (humans used to get our B12 this way too, but in today’s sanitized, modern world, the water supply is commonly chlorinated to kill off any bacteria!)

There are no whole foods plant sources of B12. This means vegans should most likely supplement with B12. There are some vegan foods which are fortified with B12, but unless your intake of these fortified products is very high and consistent, I would more than likely recommend supplementation.

Foods containing Vitamin B12 :

  • Organ meats (e.g liver, kidney)
  • Beef
  • Pork
  • Lamb
  • Chicken
  • Seafood (fish, oysters, mussels, sardines)
  • Eggs
  • Dairy (milk, yoghurt, cheese)
  • Certain products like vegemite, some breakfast cereals, some varieties of soymilk and some soy-based/vegetarian ‘meats’ are fortified with vitamin B12. Be sure to always read the label to confirm this is the case; look for ‘cyanocobalamin’ – it’s the most absorbable type for your body.
  • Mushrooms are the only non-animal based food that contains small amounts
  • Nutritional yeast

How Much Vitamin B12 Do You Need?

Human requirements for Vitamin B12 are lower than any other nutrient, with most adults requiring only 2.4 micrograms per day (a little more for pregnant and lactating women and a little less for children and younger adolescents). There is no Upper Limit to how much B12 you can safely consume in your diet as our bodies have an ability to slow down absorption rates of Vitamin B12 when we reach adequate amounts- how cool is that!

The following factors may put you at a higher risk of not getting enough vitamin B12 from diet alone:

  • following a vegetarian or vegan diet
  • being over 50 years old
  • gastrointestinal disorders, including Crohn’s disease and celiac disease
  • surgery on the digestive tract, such as weight loss surgery or bowel resection
  • metformin and acid-reducing medications
  • specific genetic mutations, such as MTHFR, MTRR, and CBS
  • regular consumption of alcoholic beverages

Vitamin B12 Supplementation

While I do not push supplements and always advocate for a food first approach, supplementation may be required for certain individuals listed above.

The research indicates that for those not getting enough through their diet, or for people with absorption issues, supplementation is an effective way to achieve adequate intakes. Because there is no upper intake (this basically means that there are no known problems of consuming too much vitamin B12 and you urinate out the excess), supplementation has not found to be harmful to health in any way.

Most individuals will need to take a supplement of 25 mcg a day or or 1000 mcg twice a week. That’s a lot of B12 but you only absorb about 0.5-1% of it.

There are a variety of supplements available including oral supplements, lozenges, oral sprays, injections. I recommend speaking to your dietitian or doctor to find the most appropriate supplement for you.

For more information on vitamin B12, please visit:

Christina Ellenberg is a Registered Dietitian and Strength and Conditioning Specialist located in the Atlanta Metro Area. Check out her website or book a session with her at www.DietitianDish.com