Vitamin B12

Brannick Clinic of Natural MedicineB12 is also known as cobalamin and is a water-soluble vitamin. It plays a key role in the normal function of the brain and nervous system and for the formation of blood.

A deficiency of vitamin B12 can cause severe and irreversible damage—especially to the brain and nervous system. Symptoms of only slightly below normal levels include: 

  • Fatigue
  • Depression
  • Poor Memory

In more serious instances:

  • Mania
  • Psychosis

Many older adults have difficulty absorbing B12 found naturally in food. This is because they don’t have enough hydrochloric acid in their stomachs. People over 50-years of age should get most of their vitamin B12 from fortified foods or dietary supplements. In most cases, this is highly effective.

People who have had gastrointestinal surgery (e.g. weight-loss surgery), or those with digestive disorders (e.g. celiac disease or Crohn’s disease), are also susceptible to low absorption of B12.

Since only animal foods have vitamin B12, vegetarians or vegans are likely to be deficient and should consider taking a high-quality B12 supplement. When pregnant women and women who breastfeed are strict vegetarians or vegans, their babies might also be deficient in the B12 vitamin.

How much B12 Do I Need?

We only require a small amount of B12 to be healthy. The dietary reference intake for an adult ranges from 2 to 3 µg per day. Unlike some vitamins, B12 has extremely low toxicity—even taking enormous doses does not appear to be harmful to healthy individuals. While extremely rare, it is possible to be sensitive or allergic to cobalamin, cobalt or other product ingredients. 

Where Can I Get Vitamin B12?

Vitamin B12 is found naturally in most animal-derived foods, including fish, shellfish, meat (especially liver), poultry and eggs. Vitamin B12 is provided as a supplement in many processed foods. It is also available as a vitamin pill, including multi-vitamins. In addition, it can be supplemented by liquid, transdermal patch, nasal spray or injection. Vitamin B12 is a common ingredient in energy drinks and is often marketed in weight-loss supplements. However, no scientific studies have shown B12 is effective for weight loss.

Consult Your Physician

It’s always best to discuss the taking of any health supplement with your physician. The path to your good health should include a strong partnership with your doctor.

Additional Resources

Office of Dietary Supplements – Nat. Institutes of Health
USDA National Nutrient Database
Harvard Health Blog