Do you need a vitamin B12 supplement?

Some people with an ileostomy or ileal conduit (urostomy) may experience a decrease in their level of vitamin B12. This is because the part of the small intestine that absorbs vitamin B12 may be removed from the digestive system during surgery. People with short bowel and people with inflammatory bowel disease (Crohn’s and colitis) are also at risk for deficiency if damage has occurred to the portion of the terminal ileum (the last part of the small intestine) that absorbs vitamin B12.

The main source of vitamin B12 in our diets comes from animal products such as meat or fish, eggs and milk. People who eat a vegan diet are also at risk for developing a B12 deficiency. (People without an ostomy, or with a colostomy, should know that as we age, some people lose the ability to absorb vitamin B12, therefore some doctors recommend B12 screening people over 50 for deficiency.)

Vitamin B12 is stored in your liver up to 2 years, therefore monitoring for vitamin B12 levels should begin around two years after surgery.

What does Vitamin B12 do?

Vitamin B12 plays important roles in our nervous system and in making new red blood cells.  Vitamin B12 deficiencies can lead to anemia (called pernicious anemia). (Anemia can also be caused by folic acid deficiency, therefore it is important to check with your doctor to discuss bloodwork for folic acid and Vitamin B12.)

You may experience the following symptoms related to deficiencies in Vitamin B12:

  •  Unexplained fatigue (extreme tiredness) due to the reduced oxygen carrying capacity of the blood
  •  Lethargy (lack of energy)
  •  Breathlessness
  •  Feeling faint
  •  Irregular heartbeats (palpitations)
  •  Headache
  •  Tinnitus (ringing in your ears)
  •  Loss of appetite
  •  Numbness, tingling in hands and feet
  •  Difficulty keeping balance
  •  Prolonged deficiency can cause irreversible nerve damage
  •  Psychological issues – depression, memory loss, dementia

Treatment of B12 Deficiency

To treat a vitamin B12 deficiency your doctor may prescribe intramuscular or subcutaneous injections. These are rapidly absorbed by your body to increase your B12 levels quickly. Oral treatment (supplements taken by mouth) is not a reliable way to increase your vitamin B12 levels; only about 1% of B12 taken by mouth gets absorbed, and absorption only happens on the last 3-4 cm of the small intestine (terminal ileum). If this area of the small intestine has been damaged or removed you will not have the ability to absorb this 1% adequately or at all. Nasal Vitamin B12 is very expensive and therefore usually not prescribed, but is available for those who prefer it.