Hair loss can be unsettling at any age. Most people are right to assume it comes down to hormones, age or genetics. However, few realise that nutritional factors can also play a crucial role. Vitamin deficiencies are not the most common cause of hair loss. However they are still an important correctable cause of increased shedding. They can also worsen existing hair thinning. They’re also difficult to diagnose as deficiencies are often subtle. Their symptoms can also overlap with many other triggers such as stress, illness or changes in hormones. In this article, we look at which vitamin deficiencies genuinely affect hair growth and how to recognise them. We’ll also review how to correct them and what you can realistically expect.
How Does Hair Grow & Why Does Nutrition Matter?
The hair follicles are highly active structures that move through repeated cycles of growth, rest and shedding. In the anagen phase, follicles produce new hair continuously. They then transition through catagen before entering the telogen phase, where the hair eventually sheds. This cycle is sensitive to stress, illness, hormonal changes and nutritional status. When the body is low in certain nutrients, it may divert resources away from non-essential functions like hair growth. This does not usually cause bald patches, but it can increase shedding or worsen existing hair thinning. It can also weaken the structure of the hair itself and lead to breakage which can give a thinner appearance.
Unlike more common causes of hair loss, vitamin deficiencies tend to be correctable. However, if they co-exist with genetic or hormonal causes of hair loss then correcting the deficiency still won’t reverse these underlying triggers. It cam however, improve overall hair quality which may reduce the fall out so to speak from things like androgenetic alopecia.
Vitamin Deficiencies vs Pattern Hair Loss
Nutritional deficiencies can cause diffuse shedding but they do not follow the distinct patterns seen in androgenetic hair loss. Male and female pattern hair loss is driven mainly by genetics and hormones. Supplements will not reverse miniaturisation of the hair follicle. Correcting deficiencies can optimise the environment for hair to grow but regrowth still requires targeted treatments such as minoxidil or DHT blockers if appropriate.
Which Vitamin Deficiencies are Linked to Hair Loss?
Thankfully, only a handful of mineral and vitamin deficiencies have good evidence linking them to increased shedding or reduced hair quality. Below are the main nutritional deficiencies that can cause hair loss:
- Iron Deficiency: This is the most common and well recognised nutritional cause of hair loss, especially in young women. Low iron stores, reflected by reduced ferritin levels, are linked to increased shedding and may worsen telogen effluvium hair loss. Iron deficiency usually occurs due to heavy periods, low dietary intake or certain medical conditions. Supplementation can help only if ferritin is genuinely low. Self-supplementing also carries risks so testing iron levels beforehand and medical monitoring is essential.
- Vitamin D Deficiency: Low vitamin D levels are widespread in the UK and less sunny countries. Emerging research suggests a link with increased shedding and possibly more severe androgenetic hair loss. It seems that vitamin D receptors play a role in the hair follicle growth cycle. Correcting a vitamin d deficiency or even prophylactically taking a dose in the winter is usually worthwhile for skin, hair and overall health.
- Vitamin B12 Deficiency: This can cause diffuse shedding and is more common in vegans, vegetarians, older adults and people with absorption issues. It often coexists with tiredness, neurological symptoms or anaemia. Supplementation is useful when levels are low.
- Folate Deficiency: This is less common but may contribute to hair shedding when present. It often accompanies vitamin B12 deficiency and so levels for both should be tested together before correcting.
- Zinc Deficiency: Low zinc levels can trigger diffuse thinning and affect the skin’s ability to heal. It is uncommon unless intake is low or specific medical issues are reducing absorption. Excess zinc supplementation can reduce copper levels and worsen hair loss, so prior testing is essential.
- Biotin Deficiency: Severe biotin deficiency is extremely rare and usually due to underlying medical disorders. If present, then correcting can help reduce hair loss. However, there is no evidence that biotin supplements improve hair loss in people with normal levels.
When Should You Get Tested?
Testing is helpful when hair loss symptoms or history suggest a higher likelihood of vitamin deficiency. It can however be hard to tell and so generally a good idea to see your doctor for blood tests if you develop hair loss especially if you notice the below:
- Persistent shedding: Especially if it lasts longer than three months.
- Heavy periods or postpartum hair loss: Iron deficiency is common.
- Fatigue or low energy: May indicate B12, folate or iron issues.
- Restrictive diets: Vegan, vegetarian or low-protein diets may reduce nutrient intake which can cause a number of vitamin and mineral deficiencies.
- Digestive conditions: Coeliac disease, inflammatory bowel disease or gastric surgery can impair absorption and cause nutritional deficiencies.
- Medical symptoms: Tingling of fingers or toes, brittle nails or frequent illness may hint at a vitamin or mineral deficiency.
In general your doctor will base testing on your medical history and examination. Common blood tests usually include ferritin, full blood count, B12, folate, vitamin D, TSH and in select cases zinc. Interpreting these with a clinician is important because some “low-normal” levels may still be adequate for hair health and do not require correction. Also some vitamins and minerals may also cause hair loss or other problems if you overcorrect.
How to Treat Hair Loss Caused by Vitamin Deficiencies
Treating deficiency-related hair loss requires a targeted and measured approach rather than taking multiple supplements at once. The best place to start is firstly getting blood tests to check whether or not you are deficient. your doctor will at the same time review of there are any other causes for your hair loss. If you have a vitamin or mineral deficiency then the best approach usually involves:
- Correct the deficiency: Use appropriate doses of supplements and/or make dietary based on blood tests and your doctor’s recommendation. It may take three to six months to see improvement in shedding if the hair loss is due to a mineral or vitamin deficiency.
- Address the underlying cause: Heavy periods, gut issues or dietary gaps need proper management to address the cause of the deficiencies. If you don’t resolve these then your hair shedding may return.
- Support the hair follicle: A balanced diet, adequate protein intake and stable general health will help the hair cycle recover.
- Use proven treatments when needed: Other treatments like minoxidil, spironolactone, finasteride or microneedling may be necessary if there is another cause of hair loss in addition to the mineral or vitamin deficiency.
- Avoid unnecessary supplements: Remember, excess levels of nutrients like zinc, iron or biotin can be harmful. Use supplements only when they are necessary.
Do Multivitamins Help Prevent Hair Loss?
Multivitamins are widely marketed for hair growth but the truth is they rarely improve hair loss if there is no deficiency to correct. They also do not treat genetic, autoimmune, scarrring or hormonal causes of hair thinning. Nor can they do anything about chronic stress or mechanical damage from tight hairstyles which all cause hair loss. However they can be useful for preventing hair loss in people with restrictive diets, postpartum depletion or on weight loss drugs. In short, it’s best to consider your health and lifestyle as a whole if you are experiencing hair loss. If there’s a vitamin or mineral deficiency then correct it. At the same time investigate whether there is an alternative explanation or additional cause of your hair loss. In all cases, reducing stress, eating a healthy diet and deploying good gentle haircare practices will help improve the health and growth if your hair.
Vitamin and mineral deficiencies can cause or worsen hair loss. However, they are rarely the main cause of hair loss and most people do not need large amounts of supplements to treat or prevent them. It is vital to test levels, correct genuine deficiencies, address underlying issues and support overall hair growth. It’s generally a good idea to seek medical help as soon as you notice hair loss especially if there’s rapid hair shedding, patchiness, itching or scaling of the scalp or loss of eyebrows or body hair. Medical assessment is also necessary if hair loss persists despite correcting deficiencies or when there are other medical symptoms to suggest an underlying health condition.
We believe that hair loss needs a personalised and targeted approach which is why we offer personalised hair loss and regrowth treatments through our online skin clinic. Our doctors create custom hair growth treatments using actives such as Minoxidil, Finasteride, Spironolactone, Melatonin, Caffeine and Tretinoin where appropriate for each and every patient. Start your virtual consultation and begin your journey to great hair today.
This article is intended for general informational purposes only and is not a substitute for medical advice, diagnosis or treatment. Always consult a qualified medical professional with any concerns about your skin or treatment options.
