Causes

What vitamin deficiency causes hair loss?

People often ask whether a vitamin or mineral deficiency can cause hair loss. There is no doubt that having a deficiency can wreak havoc on the body, with a range of often non-specific symptoms. Although the science community has yet to conclusively prove whether a vitamin or mineral deficiency can cause hair loss, there are studies which suggest you are likely reduce your hair loss by supplementing the appropriate vitamin or mineral. In this article we'll cover the common deficiencies associated with hair loss, how you can test for them, and what to do if you think it’s causing your hair loss.

How to test for deficiencies

If you believe that you have a vitamin or mineral deficiency, you should get in touch with your doctor who will be able to help identify which deficiency you may be suffering from. However, it is common for doctors to either fail to recognise the symptoms of a deficiency, or worse still, dismiss the patient as imagining these symptoms. The problem with deficiencies is that the symptoms are often non-specific, vague, and difficult to pinpoint to any particular illness.

If you find yourself in a situation where you believe you are suffering from a deficiency but you are not getting help, please do not give up! Depending on which country you live in, you can pay for a private blood test without the need for a referral from a doctor. We have listed some common services below:

Which deficiencies should I test for?

There are so many vitamins and minerals that it isn't possibly list out every one in this article. However, we will focus on the deficiencies most commonly associated with hair loss. As stated above, research on this area has mixed and conflicting results, and so this article may be updated in the future.

If you are getting a private blood test, it will be more cost-effective to get a comprehensive blood test covering multiple vitamins and minerals, rather than paying for each one separately. We have listed some common tests below:

United States

Comprehensive Vitamin Panel

Comprehensive Mineral Panel, Urine

United Kingdom

Vitamin & Minerals Home Test Kit

Vitamins & Minerals Complete Home Test Kit

Comprehensive Mineral Panel, Blood

We will now discuss some of the most common vitamin and mineral deficiencies associated with hair loss, which includes iron, vitamin D, and zinc deficiency.

Iron deficiency

Iron deficiency is the most common deficiency in the world, with various estimates suggesting it affects between 25-30% of the world’s population. Iron is a mineral required by the body to make haemoglobin, which carries oxygen around the body. If you don’t have enough iron in your body, your muscles and tissues will not get enough oxygen, which is a condition known as anaemia. Iron deficiency is not the only cause of anaemia – there are other reasons why you may be anaemic, but iron deficiency is the most common cause of anaemia.

Iron deficiency develops when you take in too little iron, or your body is losing it too quickly. Your diet might not contain iron-rich foods, and good sources of iron include red meat, beans, nuts, dried fruits, spinach, and shellfish. This is not a comprehensive list, and if you believe you are not taking in enough iron, you should discuss having a meal plan with a dietician to help boost your iron intake. The more serious issue is when your body is losing iron too quickly. This may be caused by blood loss, absorption issues, or pregnancy. If you believe your iron deficiency might be caused by ones of these issues, you should seek further advice from your doctor.

Symptoms of iron deficiency may include unexplained tiredness, pale skin, depression, and rapid heartbeat. You should note down all your symptoms, and discuss these with your doctor to confirm whether you have an iron deficiency. The focus of this article is to identify vitamin and mineral deficiencies linked to hair loss, and should not be used to self-diagnose a deficiency.

Although iron deficiency has not been overwhelmingly proven to have a clear link to hair loss, there are some patients who report hair loss when suffering from iron deficiency. The science explaining the hair loss is that when you are iron deficient and your body is not getting enough oxygen, any available oxygen supply will be diverted to the most critical organs. Your hair follicles are not considered critical and so will not receive any oxygen. This will cause them to stop working properly, and your hair may start falling out. It is worth noting that some patients with iron deficiency do not experience any hair loss.

It is recommended that if you have an iron deficiency, you should consult with your doctor who will be able to guide you on how to safely supplement to get your iron levels back to normal. If you suffered from hair loss while iron deficient, it is more than likely that this is only temporary and once your levels are back to normal, your hair will recover.

Warning: Always consult with your doctor before taking iron supplements. Iron is available in multiple forms, including over-the-counter iron supplements, high-dose prescribed iron supplements, intramuscular injection etc. Your doctor will be able to confirm whether you have an iron deficiency, and the safe level to supplement for your body.

Where to buy iron supplements?

If your doctor has confirmed that it is safe for you to take iron supplements, then check out some of the below links for iron supplements:

Vitron-C High Potency Iron Supplement with 125mg Vitamin C, 60 Count (paid link)

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Floradix Liquid Iron and Vitamin Formula 500ml (paid link)

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Solgar Gentle Iron Dietary Supplements, 25mg, 90/240 capsules (paid link)

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Vitamin D deficiency

Vitamin D is the sunshine vitamin. Vitamin D is produced when your skin is exposed to sunlight, and is also found in some foods such as oily fish, red meat, egg yolks, and breakfast cereals. This is not a comprehensive list of foods containing vitamin D, and you should be aware that it is very difficult to get enough vitamin D from food. The best source of vitamin D is the sun. Vitamin D deficiency is very common across the world, particularly in areas of the world with limited sunlight. It is estimated that 1 billion people in the world have vitamin D deficiency.

There are a number of reasons why a vitamin D deficiency might develop. For some people, a restricted diet means they do not get enough vitamin D from their food. Many nutritional sources of vitamin D are animal-based, and so those following a vegan diet may be more likely to develop this deficiency. You might also not be getting enough sun exposure. Your skin needs to be exposed to sunlight to make vitamin D, and this is not always possible in certain parts of the world where sunlight is limited. There are a variety of medical conditions that can cause vitamin D deficiency, such as digestive tract issues which can prevent your body from absorbing vitamin D from the food it processes.

Vitamin D is critical for your body to function. If you have a vitamin D deficiency, you may suffer from muscle weakness, fatigue, frequent infections, depression, bone loss, and many other frightening symptoms. As is the case with other deficiencies, the symptoms of vitamin D deficiency can often be non-specific and vague. The easiest way to confirm if you have this deficiency is through a blood test. You should not use the above symptoms to self-diagnose a deficiency. See information about the different types of tests you arrange.

Vitamin D plays a role in stimulating new and old hair follicles. It can therefore be expected that a vitamin D deficiency may reduce or prevent new hair growth. Vitamin D deficiency has also been linked to alopecia areata, which we mentioned in the article Why is my hair falling out.

Alopecia areata is an autoimmune disorder, in which the body attacks its own hair follicles which may reduce or stop hair growth. Alopecia areata literally means patchy baldness. Low vitamin D is often found in patients suffering from alopecia areata. If you are suffering from a vitamin D deficiency, you should consult with your doctor who will be able to guide you on how to safely supplement to get your vitamin D levels back to normal. You may find that this helps with your hair loss, and patients with alopecia areata are likely to see an improved outcome and enhanced response to treatment.

Warning: Always consult with your doctor before taking vitamin D supplements. Vitamin D is available in multiple forms, including over-the-counter vitamin D supplements, high-dose prescribed vitamin D supplements, intramuscular injection etc. Your doctor will be able to confirm whether you have a vitamin D deficiency, and the safe level to supplement for your body.

Where to buy vitamin D supplements?

If your doctor has confirmed that it is safe for you to take vitamin D supplements, then check out some of the below links for iron supplements:

Vitafusion Vitamin D3, 50mg, 150 Count (paid link)

Solgar Vitamin D3 1000 IU Softgels, 100/180/250 Count (paid link)

NatureWise Vitamin D3 1000 IU, 30/90/360 Count (paid link)

Buy now

Zinc deficiency

If you are not getting enough zinc in your diet, you may be at risk of suffering from zinc deficiency. Zinc is a trace element, which means that your body cannot make it on its own. Your body cannot store zinc, so you need to take it in every day to ensure you have optical levels of zinc. The top zinc rich food sources include red meat, fish, legumes, seeds, nuts, cheese, and eggs. Zinc is so important because it plays a key role in fighting infections and producing new cells.

There are many reasons why you might develop a zinc deficiency. If you have a poor diet, you may be at risk of developing a zinc deficiency. As a significant amount of zinc is absorbed from meat and fish, people on a restricted diet (such as vegetarians) may be more likely to develop a zinc deficiency. If you have stomach absorption issues (such as Crohn’s Disease), you are also more likely to develop a zinc deficiency as your body is unable to fully absorb zinc from your diet. There are many other reasons why you may be at risk of developing a zinc deficiency, and you should speak to your doctor to try to identify the cause. The easiest way to confirm if you have this deficiency is through a blood test. You should not use the above symptoms to self-diagnose a deficiency.

Given the role of zinc in cell production, it is not surprising that a zinc deficiency can cause hair loss. This is because zinc plays a key role in hair tissue growth and repair. It is worth noting that hair loss is only likely with a severe zinc deficiency, and it is very unlikely that a poor diet can result in such a level of deficiency. However, there is positive evidence to suggest that supplementing with the recommended daily intake of zinc, especially in those people with lower zinc levels, may prevent hair loss associated with zinc deficiency. You should speak to your doctor to discuss whether you may have a zinc deficiency, and whether it could be linked to your hair loss.