Vitamin B12 as methylcobalamin or cyanocobalamin
By Reed Mangels, PhD, RD
From a reader: A relative told me that older people (I am in my 70s) should take vitamin B12 as methylcobalamin instead of cyanocobalamin. She also said that I should eat eggs once a week instead of taking a vitamin B12 supplement. Is this correct?
Your relative is correct that vitamin B12 is important – it’s an essential nutrient. You can read more about vitamin B12 on our website.
My favorite source for most items related to vitamin B-12 is veganhealth.org. This website has materials developed by several vegan dietitians including Jack Norris, Ginny Messina, and myself. Jack knows a tremendous amount about vitamin B12. He provides a good discussion of the different forms of vitamin B12 here and here. He concludes, “Cyanocobalamin is a well-studied, reliable, inexpensive form of vitamin B12.” The National Institutes of Health concludes, “Existing evidence does not suggest any differences among forms [of vitamin B12] with respect to absorption or bioavailability.” I think cyanocobalamin is the form that has been shown to reverse a vitamin B12 deficiency in older people and would recommend using that form unless you have a condition that contraindicates use of cyanocobalamim.
Although eggs do contain a bit of vitamin B12, vitamin B12 is poorly absorbed from eggs. Additionally, because 10 to 30% of people older than 50 years are estimated to have low stomach acid which decreases vitamin B12 absorption from food, the Institute of Medicine recommends that vitamin B12-fortified foods or a vitamin B12 supplement be used to meet much of the vitamin B12 requirement for those 51 and older.
The contents of this posting, our website, and our other publications, including Vegetarian Journal, are not intended to provide personal medical advice. Medical advice should be obtained from a qualified health professional. We often depend on product and ingredient information from company statements. It is impossible to be 100% sure about a statement, info can change, people have different views, and mistakes can be made. Please use your best judgment about whether a product is suitable for you. To be sure, do further research or confirmation on your own.
It is NOT the National Institute of Health, it is the National INSTITUTES of Health, a collection of separate disease-oriented and organ system-organized institutes that conduct basic and clinical within their designated fields that often overlaps with the activities of the other institutes. I have been writing and developing research grant proposals for many units of the NIH for almost thirty years. Very disappointing to see that a nutrition professional who must regularly peruse NIH-funded basic and clinical research literature make such a glaring error.
Corrected. Thanks for pointing this out.