5 health conditions that can cause hair loss – and how to treat them

4th February, 2022 • 10 min read

Losing your hair, or noticing it becoming thinner, can have a big effect on your self-esteem and mental wellbeing. In many cases, addressing the cause can be the best way of managing it – but with many possible causes, this may feel difficult.

There are some common

reasons for hair loss in women
– including hormonal changes around the menopause, and stressful events such as childbirth or surgery, which can cause a type of hair loss called
telogen effluvium

But hair loss may also happen because you have an underlying health condition. In some cases, this hair loss can be permanent – but if the condition is treated, your hair can often grow back.

Keep reading to discover 5 of the most common health conditions that can cause hair loss, and the treatment options available. And because some treatments can take weeks or months to work, rest assured that there are things you can do to help your hair look its best while you wait.

Thyroid problems and hair loss

About 1 in 20 people in the UK is thought to have a thyroid problem.

Your thyroid is a gland in your neck that makes hormones to help your body function. They manage the speed at which you burn calories, how fast your heart beats and how quickly your old cells get replaced by new ones.

But if you have thyroid disease, your thyroid doesn’t make the right amount of hormones, which can cause various symptoms – including hair loss.

Hair loss symptoms caused by thyroid problems

Thyroid problems can cause different types of hair-related symptoms. You’ll usually get hair thinning that happens evenly across your head, but symptoms can include:

  • thinning of the hair on your head, or bald patches
  • thinning or absence of the outer edge of your eyebrows
  • hair that breaks easily
  • coarse or dry hair
  • hair that grows slowly or, in some cases, more quickly
  • less hair on your body, such as your arms or legs

Underactive and overactive thyroid

If you have an

underactive thyroid (hypothyroidism)
, your thyroid doesn’t make enough hormones, while if you have an
overactive thyroid (hyperthyroidism)
it makes too much. If they’re severe and left untreated, either of these problems can lead to hair loss.

In most cases, these thyroid problems are caused by an ‘autoimmune’ reaction – when your immune system mistakenly attacks your thyroid gland.

Having 1 autoimmune disease can mean you’re more likely to get another, including a different type of autoimmune hair loss called

alopecia areata
. This usually causes your hair to fall out only from certain areas, leading to small, round bald patches on your head.

Common causes of underactive and overactive thyroid:

  • Hashimoto’s disease – the most common type of autoimmune reaction that causes an underactive thyroid. Your immune system attacks your thyroid gland, causing it to become inflamed and sometimes damaged, reducing its ability to make hormones
  • Graves’ disease – the most common cause of an overactive thyroid. It’s another autoimmune condition, which in this case causes your thyroid gland to become enlarged and make too many hormones

How is thyroid hair loss treated?

If a thyroid problem is causing your hair loss, you’ll usually also have other symptoms of an over- or underactive thyroid (see the links above for details about symptoms). Your doctor can order a blood test to measure your thyroid hormone levels, which will show how your thyroid is working.

If needed, treatment can help bring your thyroid levels back to normal – but it might take a few months to work out the right dose for you. Options include:

  • for underactive thyroid – a daily tablet called levothyroxine, which replaces the hormone your thyroid doesn’t make enough of
  • for overactive thyroid – medicines such as carbimazole or propylthiouracil, which stop your thyroid making too many hormones. Sometimes other treatment is also needed, such as radioactive iodine or surgery

In most cases, once your hormone levels are under control, your hair should grow back. But it can take a few months to get the dose right and for the medication to stimulate regrowth. Be kind to yourself and give it time. You may notice your hair grows back in spurts, or that it’s a different texture or colour.

Lupus and hair loss

Many people with the autoimmune condition

– which affects about 1 in 1,000 people in the UK – notice hair loss or thinning. This can be either temporary or permanent, depending on the type of hair loss it causes.

There are 2 types of lupus that cause hair loss:

  • systemic lupus erythematosus (SLE) – this is what most people mean when they use the term ‘lupus’, where your immune system attacks your body and causes inflammation and
    such as fatigue and pain. When SLE causes hair loss, it’s usually telogen effluvium, with your hair tending to thin or shed more at the front of your hairline. This type of hair loss is ‘non-scarring alopecia’, which means it’s usually temporary. (As with autoimmune thyroid problems, it’s also possible that having SLE may mean you’re more likely to get alopecia areata)
  • discoid lupus erythematosus (DLE) – this type of lupus only affects your skin, usually in areas that are more exposed to sunlight, such as your head, neck and hands. It can lead to scaly, red or thickened patches, and if this happens on your scalp, it can stop hair follicles from growing hairs. This type of hair loss is called ‘scarring alopecia’, which is usually permanent once scarring appears – so it’s best to treat the inflammation early

Learn more about how DLE hair loss and how it’s treated in our

hair loss and scalp conditions

How is SLE hair loss treated?

Treatments for SLE don’t specifically target hair loss; rather, they help to manage the condition by reducing inflammation, which can encourage new hair growth.

Treatments for SLE include:

  • hydroxychloroquine medication – for fatigue and joint problems
  • steroid
    tablets, injections and creams – for kidney inflammation and rashes
  • rituximab and belimumab medications – for helping your immune system reduce the number of antibodies in your blood

In most cases, once treatment brings SLE under control, your hair will grow back.

In the meantime, there are certain styling techniques and other

self-care tips
you can follow to care for your hair and help it look its best.

If your hair loss is permanent, which it can be with DLE, it can be difficult to come to terms with. Remember that you’re not alone and there are support groups and resources available – try

Alopecia UK

Iron deficiency anaemia and hair loss

When you have

iron deficiency anaemia
, a lack of iron causes a lack of healthy red blood cells. This means your body struggles to carry oxygen to important organs, such as your heart. It’s the most common cause of anaemia, which affects about 2 billion people worldwide.

It can lead to iron being taken from tissues that aren’t essential to keeping you alive – such as your hair follicles – to make new red blood cells. So you may notice your hair is dry and brittle, and that more of it falls out when you brush or wash it, alongside symptoms such as tiredness, pale skin and heart palpitations.

How is iron deficiency anaemia hair loss treated?

If you think your hair loss might be caused by iron deficiency anaemia (you’ll usually have other

, too), see your doctor. They can order a blood test, and if iron deficiency anaemia is found they may:

  • prescribe iron tablets to replace your lost iron stores
  • suggest you eat more iron-rich foods, such as red meat, eggs and leafy green vegetables
  • monitor your iron levels regularly

You may need further tests to find out what’s causing you to have low iron. Treating the cause is also important – for example, if it’s caused by

heavy periods
, this might need to be investigated. Once your iron levels return to normal, your hair should start to grow again.

Polycystic ovary syndrome (PCOS) and hair loss

Polycystic ovary syndrome (PCOS)
is a common condition that affects how your ovaries work. It’s thought to happen to about 1 in 10 women in the UK.

PCOS often causes a hormonal imbalance that leads to you having higher levels of androgens, or ‘male hormones’, such as testosterone. This can cause hair growth on your face and hair loss on your head. Read more about hair loss and PCOS, and how it’s treated.

Syphilis and hair loss

is a bacterial infection that develops in stages, and is mostly passed on through sex – a
sexually transmitted infection (STI)
. It’s less common than some STIs, but it’s on the rise in the UK (more than 8,000 people were diagnosed in 2018). The first
are often sores on your genitals, rectum or mouth – known as primary syphilis.

Hair loss can happen as part of secondary syphilis, which happens a few weeks later. This stage may stop after a few weeks, or come and go for a year or so.

Your hair usually sheds in what’s known as a ‘moth-eaten’ pattern, which appears either as small patches of hair loss, or evenly across the whole of your head. It’s non-scarring alopecia, so it usually grows back with treatment.

A routine blood test can check for syphilis as part of a sexual health check, so it’s worth getting tested if you think you could be at risk.

How is syphilis hair loss treated?

If caught early, the infection itself can be easily treated with an injection of penicillin

. If you've had syphilis for more than a year, you may need more doses.

Your hair should return to normal within 3 months of treatment, and other symptoms should also improve.

When to see a doctor

If you think you might have any of these health conditions, or you’re worried about hair loss, see a doctor. They can find out what’s causing you to lose your hair and recommend the best treatment.

In some cases, lifestyle changes – including using kinder shampoos, brushes and styling techniques – will help keep your hair looking and feeling as healthy as possible.

Underlying health conditions aren’t the only possible reasons for hair loss – read about other

causes of hair loss
hair loss treatments

Or try our

Symptom Checker
to get more information about your health.

Find useful information on other areas of female hair loss with our

complete Guide

Your health questions answered

Does fibromyalgia cause hair loss?

Answered by:

Healthily’s medical team

“There’s little evidence to prove a link between hair loss and

, which is a long-term condition that causes widespread pain and extreme tiredness (fatigue). Hair loss does seem to be a common symptom listed by people with the condition, but more research is needed. Fibromyalgia itself isn’t well understood, which means it’s difficult to know whether any reported hair loss is caused by the condition itself or other things it can lead to, such as sleep problems and stress.”

Does liver disease cause hair loss?

Answered by:

Healthily’s medical team

“There are many different types of

liver disease
. In some cases, hair loss can develop when the liver is more seriously damaged. This can happen alongside other symptoms, such as coughing up blood, yellowing of your skin (
), very itchy skin and weight loss. See a doctor right away if you have these symptoms.”

Important: Our website provides useful information but is not a substitute for medical advice. You should always seek the advice of your doctor when making decisions about your health.