Can vitamin b12 cause acne?
For a long time there have been reports that a small share of people develop acne-like symptoms after receiving high doses of vitamin B12, especially after B12 injections. This has also been reported in people who had never had acne before. [1, 2, 3, 5, 5, 7] After all, these symptoms are not common acne but inflammatory skin eruptions with similar appearance. In this article, I will explain what it is all about.
But first the basics ...
Background
What is vitamin B12 and what do we need it for?
Vitamin B12 denotes a group of bioactive molecules from the group of cobalamins. It is a water-soluble vitamin that is important for cell division, blood formation and nerve function. Like any other vitamin, it is essential for our body. Without it, we cannot survive.
Where does vitamin B12 come from?
Vitamin B12 is only produced by some microorganisms, not plants nor animals. Herbivores can either use B12 from B12-producing bacteria in their digestive tract, or they consume vitamin B12 through contaminations of their plant food with stool, soil, and insects. Deliberate consumption of their own stool is also common in some types of animals such as rodents and lagomorphs (rabbit etc.) as a necessary mean to get vitamin B12 and other nutrients produced by the gut flora.
B12 is then stored in the meat and organs of herbivores. Omnivores and carnivores mainly consume vitamin B12 via the meat of the herbivores they prey.
In our modern society, we source our B12 almost exclusively from animal products and fortified foods.
Who needs to supplement B12?
Vegetarians, and especially vegans who do not eat animal foods, must use fortified foods or supplements for adequate nutrition. If this is taken into account, vegetarian and vegan diets can be very health promoting and also positively affect acne, as I will show in future articles.
People who consume animal products can also become B12 deficient, for example due to poor B12 absorption. The likelihood of such absorption issues increases with age.
In addition some types of disease or surgical procedures lead to the need of B12 supplementation. One such example is the surgical removal of the stomach and / or parts of the small intestine after which people are at very high risk of B12 deficiency which is also due to impaired absorption.
Connection of vitamin B12 and acne
When does vitamin B12 lead to acne?
Only at very high doses does B12 lead to acne-like symptoms in some people. In some cases, symptoms may occur immediately after a high dose of B12, in some cases only after prolonged supplementation, when high amounts of vitamin B12 accumulate in the body.
High doses of B12 can be administered either orally or by injection. Via injection, almost 100% of the B12 is absorbed, via oral administration only about 1% (+ 1-2 mcg. The details of B12 absorption are complex and will not be discussed here). Due to the much higher absorption from injection, it is not surprising that most reports of B12-induced acne occur after an injection. [1,2,4,5] There are also two reports of acne-like outbreaks after oral B12 supplementation. [3,7] However In both cases B12 was not taken by its own but in combination with B6 or B1, B2 and B6. Therefore B12 cannot definitely be identified as the sole cause.
We know that only a minority of people are susceptible for B12-induced “acne”. Unfortunately though, the current data does not allow to give a good estimate of the exact proportion of people who develop acne-like symptoms due to high vitamin B12 supply.
We also cannot say exactly at what dose this side effect starts to occur. In the only interventional study on the topic, one in ten participants who received B12 developed acne-like symptoms.[5] However, this was a 1000 mcg injection (with methylcobalamin) leading to a significantly higher B12 level in the blood than high dose oral supplementation does.
Women seem to be affected more often than men. [4,7]
How does B12 cause acne?
Although researchers have known for decades that very high B12 supply leads to acne-like symptoms in a small proportion of people, it was only recently discovered why. With modern gene analysis, it has been discovered that some people have a specific strain of the common skin bacterium Cutibacterium acnes (formerly Propionibacterium acnes), which increases its production of pro-inflammatory porphyrins when it is supplied with sufficient vitamin B12 by the human it lives on. [5,6] The researchers from Los Angeles write:
"[...] vitamin B12 supplementation increases P. acnes production of porphyrins, a group of proinflammatory metabolites important in acne development."6
These bacteria can produce their own vitamin B12. However, if the human being on which they live provides a high amount of B12 (after a high-dose supplementation as injection or pill), the bacteria will reduce their own B12 production and increase the production of proinflammatory substances that they exude onto the skin. These so-called porphyrins then lead to the acne-like inflammation.
Who is affected?
In addition to the above-mentioned groups that need to supplement B12, people who actually have no need for supplementation can also be affected when (unknowingly) consuming very high amounts of B12. Supplements that are advertised for various purposes may contain high-dose B12. In one study, it was a weight loss product. [7]
What can you do?
Therefore, when developing acne symptoms after the introduction of high-dose vitamin B12 supplementation, one should switch to lower-dose supplements, which are then taken more frequently (about 4-10 mcg B12 twice a day). Alternatively, B12-fortified foods (such as some soy yoghurts) must be consumed with each meal.
This only works if the normal uptake mechanism via the stomach and small intestine is intact. If you suffer from B12 malabsorption, you should find another option in consultation with a doctor. Here, options such as fortified toothpaste or a mouth or nasal spray may be useful. The research on such methods is still limited and therefore the B12 supply should be monitored by your doctor. Here, an MMA test (methylmalonic acid) or HoloTC test (holotranscobalamin) should be used, not a serum B12 test, since serum B12 test often times this does not reveal a deficiency.
If one experiences acne symptoms after having used high dose B12 supplementation for a prolonged period one should get checked for very high B12 status. If such is found discontinuation of supplementation until B12 levels have normalized should be advised. After that adequate supplementation needs to be continued if no other reliable B12 source is used in the diet or B12 cannot be absorbed.
High-dose B12 supplementation via pill or injection generally makes sense if one suffers from B12 malabsorption, as high doses via pill or injection use other uptake mechanisms than regular amounts of B12 in food.
If you experience acne symptoms after B12 injection, high-dose oral supplementation is still worth a try, as it is likely to cause fewer problems than an injection. The reason for this is, as mentioned above, that from high-dose oral supplementation only a very small proportion of B12 (about 1%) is absorbed while almost 100% of B12 is absorbed from injection. In order to meet the normal B12 requirement via high-dose oral supplementation, 2500 mcg B12 once a week is a usual dosage. Via injection 100 mcg once a month are usually sufficient.
Bibliography
[1] Brescoll J, Daveluy S. A review of vitamin B12 in dermatology. At the J Clin Dermatol. 2015; 16 (1): 27-33. https://www.ncbi.nlm.nih.gov/pubmed/25559140
[2] Balta I, Ozuguz P. Vitamin B12-induced acneiform eruption. Cutan Ocul Toxicol. 2014; 33 (2): 94-5. https://www.ncbi.nlm.nih.gov/pubmed/23815241
[3] Sherertz EF. Acneiform eruption due to "megadose" vitamins B6 and B12. Cutis.1991; 48 (2): 119-20. https://www.ncbi.nlm.nih.gov/pubmed/1834437
[4] Braun-falco O, Lincke H. [The problem of vitamin B6 / B12 acne. A contribution on acne medicamentosa (author's transl)]. MMW Munch Med Wochenschr. , 1976; 118 (6): 155-60. https://www.ncbi.nlm.nih.gov/pubmed/130553
[5] Kang D, Shi B, Erfe MC, Craft N, Li H. Vitamin B12 modulates the transcriptome of the skin microbiota in acne pathogenesis. Sci Transl Med. 2015; 7 (293): 293ra103. https://www.ncbi.nlm.nih.gov/pubmed/26109103
[6] Johnson T, Kang D, Barnard E, Li H. Strain-Level Differences in Porphyrin Production and Regulation in Propionibacterium acnes Elucidate Disease Associations. mSphere. 2016; 1 (1). https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4863617/
[7] Veraldi S, Benardon S, Diani M, Barbareschi M. Acneiform eruptions caused by vitamin B12: A report of five cases and review of the literature. J Cosmet Dermatol. 2018; 17 (1): 112-115. https://www.ncbi.nlm.nih.gov/pubmed/28594082