By Ruth Ann Clayton, RD:  In the United States, such a plentiful land, you probably aren’t concerned about being deficient in any single vitamin.  Vitamin B12, however, even though needed in small amounts, plays a large role in your quality of life.  You cannot do without B12 and deficiency is common, especially in older adults.

Initial researchers on Vitamin B12 won the 1934 Nobel Prize for Medicine and it was isolated from liver in 1948. This key vitamin is known by its generic name, cobalamin, due to its content of the metal cobalt which gives it a reddish color.  The two active forms in the body are methylcobalamin and adenosylcobalamin.  A stable synthesized form, cyanocobalamine, is converted into these active forms in the body.  Absorption is enabled in the stomach by hydrochloric acid and gastric secretions know as intrinsic factors.

The benefits of this vitamin include nerve health, cognitive enhancement and a reduction of depression as you age.  Along with folate it is proven to decrease artery damaging homocysteine levels, a risk factor in atherosclerosis, Alzheimer’s and dementia.   To prevent nervous system damage you need B12 to protect the myelin coating around your nerves.  Also your brains ability to send messages throughout nerve cells requires B12.  Other benefits include the building of red blood, nerve and bone cells.  Research with methylcobalamin form has shown effectiveness with neurological issues.

Vitamin B12 is different from other water soluble vitamins as it can be stored in the liver and other body tissues causing it to take years for a deficiency to show.  The body stores only about 2-5 milligrams (mg) of B12 if intake and absorption are sufficient.  However levels do decline with age.  A few of the symptoms of deficiency can include fatigue, sleeping problems, dizziness, poor memory and mental function, confusion, depression in older adults, and nerve damage.

Those most likely to need extra B12 are older persons, vegans and women of childbearing years.  A blood test can determine if a B12 deficiency exist.  Folate should also be checked as increased intake of B12 could mask anemia due to folate deficiency.

Animal products are the richest source of B12 including organ meats (liver, kidney), eggs, meat, fish and shellfish, and milk and cheese. Some foods are fortified with B12 but they do not provide a significant source of it. Plants are not a source thus vegetarians should consider supplementing with B12.

The Recommended Dietary Intake (RDI) is 2-3 mcg for adults with some researchers recommending 4-7 mcg for those 4 years through adults.   If you need to supplement Vitamin B12, higher doses may be needed for effective absorption.  Some therapeutic recommendations are for 2000 micrograms (mcg) for one month and then 1,000 mcg with follow-up with your doctor.  Oral B12 can produce good results with no toxicity reported.

If you think you could have a Vitamin B12 deficiency ask your doctor to do a blood test.  The earlier a deficiency is detected the sooner levels can be corrected and severe problems prevented.  Also check with your pharmacists to see if any medication you are taking can affect the absorption of B12.

Ruth Ann Clayton is the Registered Dietitian at Nature’s Way.  She has been featured in and interviewed by nationally published trade journals.   Reach her at  This information is not intended to diagnose, treat, or cure any disease.

Ruth Ann Clayton, Registered Dietitian, is active in both the American Dietetics Association and Dietitians in Integrative and Functional Medicine Dietetic Practice Group. Her nationally accredited Dietetic Internship and her years of experience in public health and hospital settings reflect her commitment to your health and well being.

As the co-owner of Nature’s Way, she uses her comprehensive background to research products, read labels, investigate manufacturers and provide information for her customers.