Vitamin B12 is another water-soluble vitamin and one of eight B vitamins. Vitamin B12 is often called cobalamin due to the cobalt found at the centre of the vitamin’s structure. There are four different forms of the vitamin,

    1. Cyanocobalamin
    2. Methylcobalamin
    3. Adenosylcobalamin
    4. Hydroxocobalamin

Role of Vitamin B12 in the Body

Vitamins never have just one role in the body. They support many pathways and systems, from metabolism to our nervous system.

Vitamin B12 plays a crucial for the development and upkeep of the central nervous system. It is also required for red blood cell formation and DNA synthesis. Vitamin B12 also helps folate prevent a particular type of anemia, known as megaloblastic anemia. Cobalamin is also required for the function of two enzymes, with countless roles throughout the body.

How Much Vitamin B12 Do I Need?

Health Canada recommends healthy individuals over the age of 14 consume 2.4 mcg (micrograms) of vitamin B12 each day. Additionally, they recommend pregnant and lactating women and teens consume between 2.6 to 2.8 mcg per day.

You can find a complete list of recommended intakes on Health Canada‘s website.

Am I At Risk of Vitamin B12 Deficiency?

Although vitamin B12 deficiency is rare, some populations have an increased risk of being deficient. People with an increased risk of B12 deficiency include, 

    • Older adults
    • Individuals with pernicious anemia
    • People taking Metformin
    • People with gastrointestinal disorders or surgery
    • People using antacids for prolonged periods
    • People consuming a vegan diet

Some signs of cobalamin deficiency include,

    • Pale or jaundiced skin
    • Weakness and fatigue
    • Pins and needles sensations
    • Changes in balance and coordination
    • Development of mouth ulcers and changes in the shape or colour of your tongue
    • Dizziness and easily short of breath when exerting yourself
    • Changes in vision
    • Shifts in mood and memory

Your vitamin B12 status can be assessed by measuring the amount of B12 in your blood. This is typically done during routine blood draws.


Can I Consume Too Much Vitamin B12?

Cobalamin is a water-soluble vitamin. This means excess amounts of vitamin B12 are not stored in the body but is lost in the urine. As a result, vitamin B12 rarely accumulates in the body or leads to toxicity. 

    Where Can I Find Vitamin B12?

    Many foods contain vitamin B12, which is why deficiency is very rare. Some foods, particularly animal-based foods such as meats and dairy products, naturally contain cobalamin. Other foods are fortified with vitamin B12. This means vitamin B12 is added to these foods during processing to increase their nutrient content.

    Some of the top sources of vitamin B12 include, 

      • Beef liver
      • Bluefin tuna
      • Atlantic salmon
      • Fortified nutritional yeast
      • Plain yogurt
      • Milk
      • Breakfast cereals
      • Bananas
      • Strawberries
      • Kidney beans

    Strawberries are a great source of vitamin B12.

    Dietary Supplements

    Although potassium can be found in some supplements, such as multivitamins or on its own, it is a very limited amount (about 80 to 99 mg). Our diet remains the best source of potassium.

    Interaction with Medications

    Many medications can affect potassium levels in our bodies. Some medications available have even been designed to reduce the amount of potassium absorbed by our bodies. Some medications to be aware of are,

    • Diuretics
      • Both loop diuretics and potassium sparing diuretics
    • ACE inhibitors and angiotensin receptor blockers

    It is important to talk with your health care team prior to starting any supplements to minimize the risk of adverse reactions.

    For more on the role of vitamins and minerals in promoting health and supporting our bodies, check out the Micronutrient Monday series.