Noticing more hair coming away when you wash or brush can be unsettling, especially when you’re unsure why. The connection between vitamin B12 and hair loss raises plenty of questions: could low levels be involved, and would taking more help? Understanding what B12 does—and what the research tells us—can help you decide where to turn for advice while continuing to care for your hair and scalp. Here's the lowdown.
Vitamin B12 and hair loss: The short answer
Vitamin B12 deficiency may be relevant to hair shedding in some people, but there is no smoking gun; the evidence is limited. Taking extra B12 has not been shown to improve hair growth when levels are already adequate. B12 is one possible part of the nutritional jigsaw, rather than a straightforward explanation for shedding.
A 2024 study involving 108 women with diffuse hair loss found no significant relationship between B12 levels and measurements of hair density and growth-cycle activity.
A retrospective study of 467 patients found lower B12 levels in the telogen effluvium group than in other hair-loss groups. But neither study tested B12 treatment, so these mixed findings cannot tell us whether supplementation improves hair.
Understanding that distinction helps you make informed choices about your health and haircare. Hair loss can also involve hormones, genetics, illness, stress, medication, or other nutritional issues. Our guide to vitamin deficiencies and hair loss explores the wider picture.
What does vitamin B12 do?
Vitamin B12 helps your body make red blood cells and supports a healthy nervous system. It also plays a role in DNA synthesis, which matters for cells throughout the body.
Hair follicles need nutrients to produce hair, but that doesn’t mean extra B12 will improve growth when you already have enough of it!
B12 comes from foods including meat, fish, eggs, and dairy, alongside fortified foods. It can be tricky for vegans: they need to find a reliable source through fortified foods or appropriate supplementation.
What signs could suggest low B12?
Changes in your hair can prompt you to look more closely at how you’re feeling, but shedding alone won’t tell you whether B12 is low. The NHS lists symptoms including:
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Unusual tiredness
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Pins and needles
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A sore tongue
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Muscle weakness
Nerve-related symptoms can occur even without anaemia.
It’s about more than diet, too. Some people struggle to absorb B12 because of conditions such as autoimmune gastritis or coeliac disease, certain medicines including metformin, or previous stomach or bowel surgery.
Talk to your GP about symptoms you’ve noticed, along with your diet, medicines and any supplements. Of course, seek prompt medical advice for new or worsening numbness or balance problems.
How is B12 deficiency checked?
A GP appointment gives you a chance to talk through your concerns about vitamin B12 and hair loss. Your GP will ask about your symptoms and health history, then decide which blood tests you need. Sometimes further tests help clarify the picture; a B12 result alone won’t explain why your hair is shedding.
Blood samples should usually be taken before B12 replacement begins, but don’t stop prescribed treatment or delay urgent care. Your GP can guide you.
What happens if you are deficient?
The priority is treating the deficiency and understanding its cause. Treatment may involve tablets or injections, depending on factors such as absorption and the clinical circumstances. The choice is based on your medical needs, rather than a promise of better hair growth.
Vitamin B12 and hair loss: will treatment help?
There is no reliable B12-specific timetable or guaranteed result. But if deficiency could be contributing to your hair changes, addressing it is important. And remember, shedding may have several causes, and correcting a blood result doesn’t necessarily resolve them all.
Hair changes take time to assess. If shedding continues or worsens, a further review can help identify other causes. For personalised hair and scalp guidance, meet Samantha Stewart MIT, Consultant Trichologist and Hair Gain Ambassador. Drop Samantha a question through her Hair Gain page for expert advice alongside any medical assessment or treatment.
Support your hair and scalp with Hair Gain
Understanding the cause of shedding and caring for your hair go hand in hand. Healthy-looking hair needs a complete approach: nutritional support from within, care for the scalp, and protection and hydration for the strands you already have. That’s the thinking behind Hair Gain’s inside-and-out approach to hair longevity.
Our Hair Capsules and Hair Gummies offer a choice of daily nutritional support. Both combine our signature AnaGain™, derived from the small but mighty organic pea shoot, with biotin and zinc, which contribute to the maintenance of normal hair. Choose the format that fits your day, alongside a varied diet.
Build on that foundation with our Hydrating Shampoo & Conditioner. Cleansing away build-up and conditioning the lengths helps keep wash days focused on hair that feels soft, hydrated and manageable.
Give the scalp its own dedicated step with our powerful yet lightweight, leave-in Scalp Foam, formulated to moisturise and care for the skin where hair grows. For lengths needing extra attention, our Hair Mask delivers a richer conditioning treatment to improve moisture, softness and shine.
Together, these different forms of care let you build a routine around your hair and scalp’s needs. Nutritional support, scalp care and conditioning each have a part to play.
Frequently asked questions
Can I have B12 deficiency without anaemia?
Yes. A normal blood count does not by itself rule out B12 deficiency. Discuss persistent symptoms with your GP.
Are B12 injections a hair-loss treatment?
They treat B12 deficiency when clinically appropriate. They are not a general treatment for every cause of thinning hair.
Should I start B12 because my hair is shedding?
Before choosing B12 or other hair vitamins, speak to your GP if you suspect a deficiency. Shedding has many possible causes, and choosing support is easier once you understand yours.
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