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29th August, 201812 min read

5 common medical causes for female hair loss

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Losing some hair each day is normal, and most women know what is typical for them. In fact, most of us shed between 90-150 hairs a day, which can sound like rather a lot but isn't anything to worry about. However, losing considerably more than this could be a sign of a bigger problem.

If you’re concerned that you're losing your hair, your first instinct may be to panic. Hair loss can be scary, and you may find that your self-esteem is affected. Try not to worry too much though. The good news is that there is usually a cause for rapid hair loss, and in some cases it can be reversed with treatment.

The first thing to ask yourself is if you've recently changed your shampoo or conditioner. Certain products just may not agree with your scalp, and you should stop using any product you think might be causing hair loss immediately.

There are some other natural causes of female hair loss including a genetic predisposition, the menopause, or old age. Since there is less that you can do to correct these causes it’s worth ruling out the things that you can change first.

Questions to ask yourself

Have you recently been under more stress than usual? If so, this can have a physiological effect on your body, which may include abnormal hair loss.

Some women find that they suffer from heavy periods regularly. This excess blood loss can lead to iron deficiency anaemia, which can in turn cause hair loss. This can sometimes be the case even when you've always experienced heavy periods, as the effect can build up over time.

If your hair loss is accompanied by excessive hair growth in other places, such as your face, or if you find that your weight has suddenly increased or decreased without explanation, then this can point to a hormonal imbalance.

A recent change in your diet can lead to a deficiency in essential vitamins and minerals required for healthy hair growth. If you're trying to lose weight, then you may be lacking some important nutrients.

Finally, ask yourself if you've taken any new medications in the last few months, or if a prescription you've been taking for some time has recently changed. Many medications can have side-effects, including hair loss, in some women.

Read more below about the different possible causes for preventable hair loss and what you can do to stop it from happening. And remember, if you're worried you may be losing your hair then you should always consult your doctor before making any further changes yourself.

Stress-induced hair loss

What is it?

Your hair’s natural growth cycle has three distinct stages: the anagen phase, where hair is actively growing; the catagen phase, where growth halts; and the telogen (or resting) phase, where the hair cuts itself off from the follicle and prepares to fall out so that a new hair can grow.

According to an article published in the American Journal of Pathology, stress triggers the release of a hormone called corticotropin-releasing hormone (or CRH), which inflames your hair follicles and encourages your hair to move straight into the resting phase. This causes your hair to thin and shed much faster than it would normally.

You are unlikely to lose hair as the result of a single, stressful episode, but long-term or chronic stress can result in patchy or thinning hair.

What can cause it?

Stress is a natural reaction to high-pressure situations. Unfortunately, prolonged exposure to difficult situations can lead to chronic stress, which may cause symptoms such as hair loss.

The exact triggers for a stress response vary from person to person, but research conducted by The Physiological Society shows that the most common causes are:

  • Starting a new job
  • Going through a divorce / separation
  • Bereavement
  • Unexpected money problems
  • A long-term illness
  • Losing your job

What to do

Stress management techniques can help to manage your body’s response to difficult situations, and prevent the release of stress hormones like CRH.

Some effective ways to cope with stress include:

  • Regular exercise
  • Exploring mindfulness
  • Using calming breathing exercises
  • Scheduling time to relax and unwind
  • Setting yourself goals and challenges
  • Developing time management techniques

The Royal College of Psychiatrists recommends sharing your problems with friends and family too. This might be difficult to do at first, but it has been shown to reduce stress levels, and it might even help you to fix the situation that’s causing your stress.

Once your body stops releasing stress hormones, your body’s growth cycle will slowly regain its natural rhythm and your hair will start to grow back on its own.

Iron deficiency anaemia

What is it?

Articles published in the Journal of the American Academy of Dermatology show a strong link between iron deficiency anaemia and hair loss.

This is because iron deficiency anaemia reduces your red blood cell count and inhibits your body’s ability to deliver oxygen to vital organs like the heart. To counteract this process, your body will scavenge iron from non-essential tissue like your hair follicles and use it to produce new red blood cells.

Over time, this process stops your hair from developing properly and causes it to fall out. There is also some evidence to suggest that iron deficiency anaemia inhibits the expression of certain growth enzymes which would further explain why the two conditions appear to be connected.

What causes it?

Iron deficiency anaemia is a condition that occurs when the body’s iron stores are depleted, which causes a reduction in red blood cell production. Common causes of iron deficiency include:

  • Blood loss (e.g. from frequent, heavy periods)
  • Insufficient dietary iron intake
  • A gastrointestinal disorder like coeliac disease

According to statistics published by both the BMJ and the American Family Physician, iron deficiency anaemia affects between eight and nineteen percent of women - depending on factors like race, age and lifestyle.

You may be at more risk of developing iron deficiency anaemia if you have heavy periods or don’t eat enough iron-rich food.

What to do

Treatment for iron deficiency anaemia depends on the underlying cause. For many young women, heavy periods, pregnancy or a gastrointestinal disorder are the most likely causes. In some cases, you may simply not be getting enough iron in your current diet.

Most treatments will centre around correcting these issues, and replacing lost iron through iron supplementation and/or by adding more iron-rich foods to the diet.

Some examples of these iron-rich foods include:

  • Dark green vegetables like kale or spinach
  • Breads or cereals that are fortified with iron and other minerals
  • Brown rice
  • Nuts and seeds
  • Pulses and beans

If you have iron deficiency anaemia, or you think your hair loss might be caused by this condition, it is important that you see your doctor as soon as possible. The condition requires careful management and you will need to have your iron levels monitored regularly. Your doctor may also want to prescribe an iron supplement if your levels are very low.

Once your iron levels return to normal your hair should start to grow back on its own.

Hormonal imbalance

What is it?

An article published by the American Hair Loss Association shows that an overabundance of androgen hormones like testosterone or DHT can cause female hair loss. When they are not kept in check by sufficient levels of oestrogen these hormones start to bind themselves to your hair follicles, causing them to shrink.

Over time, this reduces the width of the individual hairs produced with each growth cycle - causing your hair to become fragile and thin. If you are suffering from hair loss as a result of a hormonal imbalance you may also notice a paradoxical increase in facial hair, which is triggered by the presence of DHT.

What causes it?

Your hormones can become imbalanced for a number of different reasons. Certain medications can cause fluctuations in oestrogen production, as can pregnancy, the menopause or the natural aging process. This creates an artificial ‘spike’ in androgen hormones, and causes DHT to start binding to your hair follicles.

Conditions like polycystic ovary syndrome (PCOS) and hypothyroidism can also cause the kind of hormone fluctuations that trigger female hair loss. In fact, PCOS actually stimulates the release of excess testosterone, and the link between PCOS and female hair loss is quite strong.

What to do

Hormone imbalance caused by pregnancy normally evens out after giving birth. In the case of conditions like PCOS or hypothyroidism, treatment is needed. This normally involves taking prescribed medications that are designed to rebalance your hormones.

Oestrogen and progesterone replacement therapies (HRTs) can also help to slow hair loss caused by a hormonal imbalance, particularly if your hair loss is a result of the menopause.

If you are worried that you are suffering from a hormone imbalance you should book an appointment with your doctor. They will be able to diagnose the condition correctly and start an appropriate treatment plan.

Unfortunately, hair follicles damaged by DHT cannot be returned to their natural state. This means that hormone-related hair loss is best avoided by treating any imbalances as soon as they occur.

Hair loss due to weight loss

What is it?

An article published in Dermatology Practical and Conceptual describes a strong connection between hair loss and a number of different nutrient deficiencies, including zinc deficiency, protein deficiency, niacin deficiency and inadequate amounts of both vitamin A and vitamin D.

This is because your hair - like any other part of the body - has complex nutritional needs. If these needs aren’t met your body will not be able to form strong hairs or prolong the anagen (or growing) phase for long enough.

Over time, you may notice your hair becoming more brittle to the touch. You may also notice an increase in hair shedding or the emergence of bald spots.

What causes it?

A number of diets are known to cause nutrient deficiencies. This is particularly true of the low calorie diets that people use to lose weight quickly, but it is also true of certain fad diets which recommend cutting out one or more food groups.

According to the article mentioned above, any diet that could significantly decrease your intake of protein, zinc, vitamin E, vitamin D or vitamin A or niacin could cause hair loss.

Rapid weight loss as the result of an illness can also cause nutrient deficiencies.

What to do

If you are worried you might be losing hair as the result of a nutrient deficiency you should book an appointment with your doctor as soon as possible. Nutrient deficiencies may occur as the result of a more serious medical condition, which only a doctor can diagnose.

In most cases, your doctor will recommend moving towards a balanced and healthy diet to begin correcting your nutrient deficiency.

In particular, your doctor may recommend a diet rich in:

  • Oily fish, walnuts or chia seeds
  • Spinach, kale and other dark green vegetables
  • Dairy produce or eggs
  • Lentils, pulses and beans

These foods are all rich in a variety of vitamins, minerals and macronutrients that can help to restore natural growth. Increasing your protein intake may also help to improve the quality of your hair.

Once your body has access to the nutrients it needs, you should find that your hair starts to grow back on its own.

Hair loss and medication

What is it?

An article published in Drugs - Real World Outcomes shows that some prescription drugs cause hair loss by interfering with the delicate chemical processes that regulate your hair’s natural growth cycle.

Any drug that lists hair loss as a side effect can, in some cases, trigger a condition called telogen effluvium, where individual hairs are prompted to move into the telogen (or resting) phase too quickly.

This causes your hair to thin and shed. You may also notice some bald spots if you have been using the medication for a long time.

Exceptions include examples like chemotherapy drugs, which actively attack fast-growing cells like the ones found in your hair follicles.

What causes it?

A number of different medications list hair loss as a potential side effect. This includes anticoagulants like warfarin or heparin, cholesterol lowering medications like Lopid, antifungal treatments, chemotherapy drugs, antidepressants and some birth control pills.

An overabundance of vitamin A has also been linked to hair loss, implicating some supplements, and the majority of acne treatments.

What to do

If your medication is causing hair loss as a result of telogen effluvium, there is no reason to worry. The effects are not permanent, and your hair should resume its natural growth pattern once you have finished taking the medication.

Unfortunately, many of the medications that cause hair loss are needed to treat serious medical conditions, and you may need to use them permanently in order to manage an illness.

In these cases, you may be able to switch to an alternative medication. Remember, you should never stop taking a medication without consulting your doctor first. If you think you are suffering from hair loss as a result of your medication, book an appointment as soon as possible so that you can discuss your options safely.

Other causes of hair loss

If you do not think that your hair loss is a result of the 5 common causes outlined above you should consult with your doctor. They will be able to help diagnose the problem and recommend appropriate treatment options.

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