Vitamin B12 is a water-soluble vitamin bound to protein in animal foods including meat, fish, chicken, eggs, yogurt, cheese, and milk. As we age, our body is less able to absorb B12 and over time a B12 deficiency can lead to cognitive problems and mood dysfunction.
Vitamin B12 plays an important role in neurological function, making red blood cells, and DNA. Like most vitamins, our body can’t make B12, which means that we need to get it from our food. B12 is found primarily in animal products, including fish, chicken, pork, red meat, milk, yogurt, and cheese. Nutritional yeast is also a good source of B12. Synthetic B12, which often is better-absorbed than the B12 found naturally in foods, is added to breakfast cereals and non-dairy milks such as almond milk, soymilk, and rice milk.
One important yet often overlooked side effect of aging is decreased production of hydrochloric acid in the stomach, which affects 10-30% of adults and leads to decreased absorption of vitamin B12. B12 deficiency can lead to megaloblastic anemia, fatigue, weakness, constipation, loss of appetite, weight loss, numbness and tingling in hands and feet, difficulty maintaining balance, depression, confusion, dementia, poor memory, and sores in the mouth or on the tongue. Since many of these symptoms occur as we age, it’s important to rule out a possible B12 deficiency.
Metformin, a common medication used to control type 2 diabetes, decreases body levels of B12 that can lead to peripheral neuropathy or numbness and tingling in the feet and hands. In fact, 10-30% of people on metformin for more than 6 months experience a B12 deficiency.
The Recommended Dietary Allowance (RDA) for B12 is 2.4 mcg per day for women and men age 14 years and older. The Daily Value (DV) for vitamin B12 is 6.0 mcg. In the United States, the estimated average daily intake of vitamin B12 is about 5 mcg per day for men and 3.5 mcg per day for women, which looks like we get plenty of B12. However, because between 10% and 30% of older people are unable to absorb vitamin B12 from foods, the Institute of Medicine recommends that people older than 50 years of age consume foods fortified with B12 or supplements containing B12 to improve absorption.
Use these 4 tips to make sure you’re consuming optimal amounts of vitamin B12:
- Include protein foods that contain B12 (like fish, chicken, beef, cheese, yogurt, or milk) at every meal.
- If you don’t use dairy products, choose non-dairy milks that are fortified with B12.
- Include 1-2 servings of breakfast cereal fortified with B12 in your daily food choices. Add cereal to yogurt or enjoy a bowl of cereal and milk as a snack.
- Talk with your physician about your B12 status.
By Lynn Grieger RDN, CDE, CPT, CWC
National Institutes of Health, Office of Dietary Supplements. Vitamin B12 Dietary Supplement Fact Sheet. https://ods.od.nih.gov/factsheets/VitaminB12-HealthProfessional/ Updated 2-11-2016. Accessed 1-15-17.
Ryan-Harshman M, Aldoori W. Vitamin B12 and health. Canadian Family Physician. 2008;54(4):536-541.
Roy RP, Ghosh K, Ghosh M, et al. Study of Vitamin B12 deficiency and peripheral neuropathy in metformin-treated early Type 2 diabetes mellitus. Indian Journal of Endocrinology and Metabolism. 2016;20(5):631-637. doi:10.4103/2230-8210.190542.
Stephanie Ronco has been editing for Food and Health Communications since 2011. She graduated from Colorado College magna cum laude with distinction in Comparative Literature. She was elected a member of Phi Beta Kappa in 2008.