Can Vitamin B12 Cause Acne? What the Research Says
Short answer: yes, in some people. High doses of vitamin B12, especially injections and high-dose supplements, can trigger a sudden breakout of small, uniform red bumps on the face, usually within days of starting. Researchers have found that extra B12 changes how skin bacteria behave, pushing them to make inflammatory compounds linked to acne. For most people, B12 from food does not cause breakouts.
Can vitamin B12 cause acne?
Doctors have reported acne flares from vitamin B12 since the 1970s, when German dermatologists described 14 patients whose acne appeared or worsened during B6 and B12 treatment, most of them women (Braun-Falco and Lincke, 1976). Case reports have continued since. In a 2024 report, a woman developed an acne-like eruption two days after her first high-dose B12 injection, and it cleared within about two weeks (Owen et al., 2024).
This is not common. Most people take B12 without any skin change. But if your breakouts started or got worse after you began a B12 supplement, B12 shots, an energy drink, or a high-dose B-complex, the timing is worth paying attention to.
Why does B12 cause breakouts in some people?
The clearest explanation comes from a 2015 study in Science Translational Medicine. Researchers found that when people took B12, the acne-associated skin bacterium C. acnes (formerly P. acnes) switched off its own B12 production and started making more porphyrins, compounds known to drive inflammation in acne. One of the ten healthy volunteers developed acne about a week after starting B12 (Kang et al., 2015).
In other words, the extra B12 does not clog pores directly. It changes what the bacteria already living on your skin are doing.
What does B12 acne look like?
| B12-triggered breakout | Typical acne | |
|---|---|---|
| Onset | Sudden, usually days to a couple of weeks after starting high-dose B12 | Gradual, often over months or years |
| Look | Many small, similar-looking red bumps and pustules (called "monomorphic") | A mix of blackheads, whiteheads, pimples and sometimes cysts |
| Blackheads | Usually absent | Common |
| Where | Face (forehead, nose, cheeks, around the mouth), sometimes chest and back | Face, chest and back; jawline and chin in hormonal patterns |
| What makes it go away | Often improves within weeks once the high dose stops | Depends on the underlying cause |
Who is most likely to break out from B12?
- People getting B12 injections or taking high-dose B12 (often 1,000 mcg or more daily)
- People stacking several products that each contain B12: a multivitamin, a B-complex, an energy drink, a "hair, skin and nails" supplement
- People who already have acne-prone skin
Check your labels. It's common to be taking far more B12 than you realize, spread across products you'd never think of as a "B12 supplement".
Does low B12 cause acne?
There isn't good evidence that low B12 causes acne. The research points the other way: too much B12 is the known trigger. That's why guessing is risky. People with stubborn acne often add B vitamins "for their skin" without knowing their level, and if it was already normal or high, the extra may be making things worse, not better.
What to do if you think B12 is breaking you out
- Add up your intake. List every supplement, drink and shot that contains B12, with the dose.
- Talk to your doctor before stopping anything prescribed. If you get B12 injections for pernicious anemia or another deficiency, you need that B12. Your doctor can adjust the dose or route and treat the breakout.
- Know your level. A blood test shows whether your B12 is low, normal or high, so you're not guessing about whether you need a supplement at all.
- Give it time. In reported cases, B12-triggered eruptions usually settle within a few weeks after the high dose stops.
How BreakoutLabs measures B12
Vitamin B12 is one of the 12 biomarkers in the BreakoutLabs Acne Root Cause Test, alongside hormones (Free and Total Testosterone, SHBG, DHEA-S, Albumin), stress and inflammation markers (Cortisol, hsCRP), other nutrients (Vitamin D, Ferritin, Creatinine) and blood sugar (HbA1c). You collect a small blood sample at home with a painless device on the back of your upper arm, it's processed in a CLIA-certified lab, and results are ready 5 business days after the lab receives it. Your Clear Skin Blueprint shows where your B12 sits, so you can see whether your supplement stack is helping or getting in the way. Learn more about the test.
Frequently asked questions
How long does B12 acne last?
In published cases, B12-triggered eruptions usually improve within a few weeks after the high dose is stopped or reduced. If breakouts continue well beyond that, something else is likely involved.
Can B12 in a multivitamin cause acne?
It can if the total dose is high or you're combining it with other B12 sources. Standard food-level amounts are rarely a problem; the reported cases mostly involve injections and high-dose supplements.
Does biotin cause acne too?
Biotin is also commonly linked to breakouts, though the evidence is weaker than for B12. If you started a biotin or "hair, skin and nails" supplement around the time your skin changed, mention it to your doctor.
Should I stop taking B12 if I have acne?
Not without talking to your doctor, especially if B12 was prescribed. The better first step is finding out whether you actually need it by checking your level.
Sources
- Kang D, Shi B, Erfe MC, Craft N, Li H. Vitamin B12 modulates the transcriptome of the skin microbiota in acne pathogenesis. Science Translational Medicine. 2015.
- Owen JJ, Youssef RM, Altman K. Vitamin B12–induced acneiform eruption. Baylor University Medical Center Proceedings. 2024.
- Braun-Falco O, Lincke H. The problem of vitamin B6/B12 acne. MMW Münchener Medizinische Wochenschrift. 1976.
This article is for educational purposes and is not medical advice. Talk to your healthcare provider before changing any prescribed treatment.
