During a time of upheaval in our nation, Lou Gherig, America’s baseball iron horse, received a diagnosis that completely changed his life. In the face of his own uncertain future Lou Gherig stood before over 60,000 people and delivered a speech in which he shared the “bad break” of his recent diagnosis with ALS. Yet, in the face of his own personal, uncertain future, he stated, “I am the luckiest man alive.” He died a little over two years later.
While there is no cure for Lou Gherig’s disease, some researchers have found high dose injections of a form of vitamin B12 (methylcobalamin) has a protective effect on neurons and slows down progression of the disease.1 Supplementing with vitamin B12 can be very important for many, though, not just those diagnosed with ALS.
To supplement or not to supplement?
The Institute of Medicine (IOM) recommends that everyone over 50 years of age ensure adequate B12 intake by supplementing and/or consuming fortified foods. Vitamin B12 is easier to absorb from these sources.
Individuals taking medications for acid reflux, such as proton pump inhibitors (PPIs) or metformin would do well to supplement. Metformin is a medication typically given to manage type 2 diabetes. It’s been found to impair the body’s ability to absorb vitamin B12.2 This can go unrecognized, though, as blood levels of B12 can be reduced within the first three months of metformin use even though symptoms may not appear for over a decade. Two thousand individuals with type 2 diabetes were divided into two groups who took either vitamin B12 or metformin. After three years, low levels of B12 were much more common in the metformin group than the placebo group.3Diabetics taking this medication would do well to have these levels checked periodically or to proactively/preventively supplement.Vitamin B12 deficiency may be especially pronounced in elderly diabetics taking metformin.
It’s estimated that 25-35 percent of Americans take PPIs or a similar medication to treat acid reflux. Even more shocking is the 2009 statistic of 2.6 million prescriptions given to children for PPIs. Aside from their impact on proper digestion, PPIs limit the body’s ability to properly metabolize B12 so it can benefit us.
Many omnivores have suboptimal levels of B12.
Various countries have documented the common occurrence of subnormal vitamin B12 status in vegetarians or vegans. A study in Hong Kong found that when vegans and those living in underprivileged communities in northern rural China supplemented with vitamin B12, risk factors of cardiovascular disease improved.4
It has also been observed that when dietary changes are made from being an omnivore to a strict plant-based diet for five years, serum B12 levels do decrease. When supplements or vitamin B12-fortified foods are included in the diet, this reduction doesn’t occur. However, evidence seems to indicate that a steady decline over a five-year study period still occurs when fortified foods alone are the source of B12, indicating that additional supplementation may be needed in addition to the fortified foods. Eating small amounts of animal products does not guarantee sufficiency. Many omnivores have suboptimal levels of B12.
Injectable or sublingual?
Vitamin B12 supplements can be swallowed, chewed, dissolved under the tongue, absorbed in the mouth via toothpaste, or injected in the muscle. Injections are commonly given in doctor’s offices when deficiencies are identified. Studies have found, however, that sublingual or oral doses can be just as effective in raising serum B12 levels in the long run. Evidence from some studies has found that treating symptoms of deficiency, such as neurological deficits, in individuals with 1,000-2,000 mcg of oral B12 may be as effective as injections.5 Injections, however, are necessary for those with genetic defects in B12 metabolism. Other research using doses as low as 350 mcg per week (50 micrograms per day) of vitamin B12 supplementation showed equal improvement to those taking 2000 micrograms per week in vegans and vegetarians with borderline deficient levels.6
The recommended daily allowance (RDA) is only 2.4 mcg. While B12 is water soluble, it’s stored in the liver for a long time and therefore daily ingestion is not necessary. Smaller doses can be taken daily, or larger doses if you supplement a few times a week. In their book Vegan for Life, dietitians Jack Norris and Virginia Messina recommend the following:
• Consume two servings per day of fortified foods providing 1.5 to 2.5 mcg of vitamin B12 each.
• Take a daily vitamin B12 supplement of at least 25 mcg (25 to 100mcg is a good range).
• Take a supplement of 1,000 mcg of vitamin B12 three times a week.
B12 exists in four forms. It is beyond the scope of this article to properly address the forms but in a nutshell, cyanocobalamin or methylcobalamin are two forms typically found in supplements. Cyanocobalaminis a stable form and converted in the body to more active forms. It does contain trace amounts of cyanide, which, if taken in correct dosages, is considered within safe limits. However, individuals with kidney disease should supplement with methylcobalamin instead. Methylcobalamin is a more active form of B12 that doesn’t require any conversion for some of its uses. The stability of methylcobalamin is unsure, so supplements contain higher amounts to ensure adequacy.
I would encourage supplementation for those over 50 years of age, those taking certain medications, those thriving on a plant-based diet, those with digestive concerns, and those who’ve tested and have marginal or suboptimal levels. I have a general preference for sublingual and even recently purchased the toothpaste just to B sure.
In a world of so much uncertainty, I’m so thankful that Jesus is a sure Foundation. In Him we are the luckiest in the world, to B sure!
1. Y. Izumi & R. Kaji, “Clinical trials of ultra-high-dose methylcobalamin in ALS,” Brain Nerve, October 2007, https://www.ncbi.nlm.nih.gov/pubmed/17969354.
2. A. Strong et al., “Sublingual vitamin B12 compared to intramuscular injection in patients with type 2 diabetes treated with metformin: a randomised trial,” N Zeal Med J, 2016, https://www.nzma.org.nz/journal/read-the-journal/all-issues/2010-2019/2016/vol-129-no-1436-10-june-2016/6920.
3. 3. V. Aroda, S. Edelstein, R. Goldbert, et al., “Long-term Metformin Use and Vitamin B12 Deficiency in the Diabetes Prevention Program Outcomes Study,”J Clin Endocrinol Metab,https://www.ncbi.nlm.nih.gov/pubmed/26900641.
4. S. Woo et al., “Vegan diet, subnormal vitamin B-12 status and cardiovascular health,” Nutrients,https://www.ncbi.nlm.nih.gov/pubmed/25195560.
5. J. Vidal-Alaball et al., “Oral vitamin B12 versus intramuscular vitamin B12 for vitamin B12 deficiency,” Cochrane database of systematic reviews, July 20, 2005, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5112015/.
6. C. Del Bo’ et al., “Effect of two different sublingual dosages of vitamin B12 on cobalamin nutritional status in vegans and vegetarians with a marginal deficiency: A randomized controlled trial,” Clin Nutr, February 14, 2018, https://www.ncbi.nlm.nih.gov/pubmed/29499976.
Risë Rafferty, RDN
Risë is a Registered Dietitian Nutritionist (RDN) and has been writing and teaching about health for many years. She loves the health message and takes great pleasure in seeing people thrive by the application of its principles. Her research and down-to-earth manner allow her to offer up the health message in both an intelligent and accessible manner. She and her husband, James Rafferty, have two children.
