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Hair Loss Reasons and Causes

Hair Loss Reasons and Causes

Types of hair loss

When you think about hair loss, does the image of a balding middle-aged man spring to mind? It's a common stereotype, after all. But the truth is there are about 50 different hair loss disorders, and women are affected too. The medical term for hair loss is alopecia, and some types of alopecia are more common than others. Male-pattern baldness, for instance, is thought to affect around half of all men by the time they reach their 50th birthday (i). Meanwhile, another type of hair loss  - alopecia areata - is thought to affect one to two in every 1,000 people in this country (ii).

Here's what you should know about the main types of alopecia:

Androgenetic alopecia

Also known as male-pattern baldness, androgenetic alopecia is the most common type of progressive hair loss. It also affects women, and according to the National Institute of Health and Care Excellence (NICE), about a third of white women over the age of 70 are affected by what's commonly known as female-pattern baldness (iii).

In men, androgenetic alopecia runs in families, though whether or not there is a genetic link in women with female-pattern baldness is less clear. It's caused when the male sex hormone testosterone converts to another hormone called dihydrotestosterone (DHT), which affect the hair follicles on the scalp, making them produce thinner hairs and eventually stopping hair production altogether.

The pattern of hair loss is different in men than women. Men usually start to be affected in their late 20s or early 30s, starting with a receding hairline and thinning hair at the top and front of the head. In women, on the other hand, the hair line is usually unaffected, and thinning usually happens around the crown area.

Alopecia areata

Alopecia areata can affect men and women of any age, though according to Patient about half of cases develop in children, with 80 per cent of cases starting in people younger than 40 years old (iv). Alopecia areata causes small round patches of hair loss on the scalp, but other types of alopecia include alopecia universalis – which affects hair anywhere on the body (including eyebrows and under-arms) – and alopecia totalis, which is when all of the hair of the head is lost.

Many cases of alopecia areata are caused by problems with the immune system, such as diabetes, overactive thyroid and lupus, and experts believe some people may be genetically predisposed to developing it if they have family members who are affected (according to experts anything up to 8.6 per cent of adults with alopecia areata have a family history of the condition (v) ).

It has also been linked with stress. The good news is in many cases, the hair grows back without any treatment.

Telogen effluvium

Unlike some types of hair loss that causes bald patches, telogen effluvium is characterised by general shedding from all over the head. It's normal to lose 100 or so hairs a day, but this shedding can increase when your body reacts to things like physical and emotional stress, illness, hormone changes, dietary changes or certain medicines. Telogen effluvium is usually temporary, and hair starts to grow back within six months.

Anagen effluvium

This is the type of hair loss mainly seen in people having chemotherapy treatment. As well as affecting the scalp, it may cause loss of hair from other parts of the body and face. Like telogen effluvium it's usually temporary, and hair grows back within a few months of finishing treatment.

Hair loss in men

In men, the most common type of hair loss by far is male-pattern baldness. Indeed, for the majority of men, hair loss or thinning hair is an inevitable fact of life. Male-pattern baldness is thought to affect 7.4 million men in the UK (vi), with Caucasian men the most likely to be affected.

This pattern of hair loss varies, from a slightly receding hairline or hair that's generally less thick than it used to be to a bald patch on top, advanced receding from the front of the head or generally very thin hair, including the familiar rim of hair around the back and sides of the head. Some men lose all their hair, leaving them with nothing on their scalp. Discover more about the causes of hair loss in men

What causes it?

Hormones are involved in the changes that cause hair to stop growing. When testosterone the main male sex hormone is converted into another hormone called dihydrotestosterone (DHT) in the hair follicles, the affected follicles start to become smaller than normal, and the hair they produce starts to thin at the same time. In time, the affected hair follicles are so small that they only produce a fine hair that grows below the surface of the skin.

As to why some men have hair follicles that are sensitive to these hormonal changes while others don't, it's now accepted that male-pattern baldness is a genetic condition. At the same time, many men who lose the hair on their scalp have much more hair on their bodies than others. This again is a result of hormonal activity (though it doesn't mean men who are affected by male-pattern baldness produce more testosterone than those who aren't).

What can you do?

If you have a genetic predisposition for male-pattern baldness and your hair is starting to thin, there is some medication you can try.

In the meantime, making sure your diet has a good supply of certain nutrients may be a good idea to keep your hair and scalp as healthy as possible for as long as possible:

Don't pass on protein

Your body needs a good supply of protein to make new hairs (hair is, after all, made mostly from protein). So make sure you're getting the protein you need, including fish, chicken and lean cuts of meat, as well as low-fat dairy products, eggs and beans. Eating meat, chicken, fish and beans also keeps your iron levels topped up (not having enough iron can also cause hair loss).

Eat more carrots

Foods rich in beta-carotene, which your body converts to vitamin A, may help to keep your cells healthy, including those on your scalp. Red, yellow and orange fruit and vegetables are good sources, plus some dark green leafy veg. Similarly coloured foods, including oranges, peppers and tomatoes, are also rich in vitamin C, a nutrient your body needs to make collagen (collagen is found in your hair as well as your skin).

Think zinc

Zinc is a mineral that helps to keep the sebaceous glands attached to your hair follicles healthy, so make sure you're getting enough foods that contain it, such as seafood, poultry, eggs, nuts and seeds.

Boost your Bs

Vitamins B6, B12 and folic acid help to carry oxygen around your body, including to your hair follicles. Low-fat protein foods such as chicken, fish, eggs and beans may help increase your levels of B6 and B12, while eating green leafy vegetables and fortified cereals may boost your folic acid intake.

Hair loss in women

Hair loss may be thought of as less common in women than it is in men, but you may be surprised to find out how many women are affected. Before the menopause, fewer than 10 per cent of women have some degree of hormone-related hair loss (iii). But after the menopause, this figure is thought to rise to a third in those aged 70 and older (iii).

However, hormones aren't always the cause of hair loss. For women as well as men, taking certain medicines can cause hair loss, including anticoagulants (medicines that thin your blood), some antidepressants and some heart and blood pressure medicines. If you suspect you have a problem with hair loss that's linked to a medicine you're taking, speak to your GP, as an alternative may be available.

Here are some of the other things that may be causing your hair loss:

Thyroid disease

If your thyroid gland produces too much or too little thyroid hormone – that is, if you have an overactive or underactive thyroid – one of the symptoms could be hair loss. Other symptoms of hyperthyroidism and hypothyroidism include hyperactivity, irritability and insomnia (overactive) and feeling cold and tired all the time (underactive).

Women are 10 times more likely to have an overactive thyroid gland than men (vii) and are more likely to have an underactive thyroid too (viii). So if you suspect you have a problem with your thyroid, ask your GP for a blood test. The good news is both conditions can be easily treated with medicines, which usually help to restore your hair to normal.


In women of child-bearing age, iron-deficiency anaemia can be caused by heavy periods and pregnancy. Anaemia is a condition caused by a reduced number of red blood cells or haemoglobin in your bloodstream, which means your body's cells and organs don't receive the amount of oxygen they need (as red blood cells carry oxygen in the blood). Common symptoms include tiredness, shortness of breath and palpitations. Hair loss is also a symptom (chronic telogen effluvium). Eating more iron-rich foods may help, including fish, eggs, poultry, red meat, beans, tofu and dark green leafy vegetables.


After having a baby, it may seem as if you're losing far more hair than normal. This is because most women lose less hair than normal when they're pregnant, and when your body's oestrogen levels decrease after childbirth, all that extra hair starts to fall along with your normal hair shedding. The good news is this is usually temporary, and your hair should start to settle back to its normal shedding pattern once your hormone levels become more balanced.

Weight loss

Losing a dramatic amount of weight can result in thinning hair, especially if you have been following a strict weight-loss diet and you haven't been getting the right amount of nutrients, including protein, vitamins and minerals. If you're losing weight and your hair is thinning, it could also be a sign that you have an eating disorder such as anorexia. If, on the other hand, you have lost a lot of weight without trying, see your GP as it could be a symptom of a medical condition.


This impulse control disorder causes people to pull out their own hair. It’s more common in teenagers and young adults, says the NHS, and tends to affect more girls than boys (ix). It can leave you with bald patches on your scalp, as well as on other parts of your body such as your eyelashes and eyebrows. If diagnosed with trichotillomania, you may be offered cognitive behavioral therapy or another type of psychotherapy as part of your treatment.

Polycystic ovary syndrome

Millions of women in the UK are affected by PCOS (according to the PCOS charity Verity, one in 10 is affected (x)). If you have PCOS, you may develop cysts on your ovaries, you may have high levels of androgens (male hormones) or your ovaries may not release an egg on a regular basis. One of the symptoms of PCOS is thinning hair and hair loss. Weight gain, excessive hair growth and acne are among the other symptoms. Treatments include diet, exercise and hormone therapy. For more information Polycystic Ovary Syndrome, why not have a look around our dedicated Hub. 

Learn more about the causes of hair loss in women in our helpful guide.

Hair loss myths and facts

The subject of hair loss has more of its fair share of old wives' tales. Here are some that are true and some that are just myths:

TRUE: Steroid abuse is linked to hair loss

Anabolic steroids are often taken illegally by athletes, weightlifters and bodybuilders to boost muscle mass. But it’s thought they may also increase levels of male hormones that trigger baldness (xi).

FALSE: Hair styling can make you bald

Using hair products such as gel, mousse and styling cream doesn't have an affect on how much hair you have. And while too much heat styling can burn or dry your hair and cause some of your hairs to fall out, they grow back normally. However, certain types of extreme styling such as hair weaves or using chemical relaxers may harm the roots of your hair, causing it to fall out permanently.

TRUE: Stress causes hair loss

This is probably true, but usually only in major cases of psychological stress, such as after the death of a loved one. Physical trauma such as a severe illness or an accident may also cause temporary hair loss.

FALSE: Going bald is passed down through mothers

Baldness does run in families, but experts think you can inherit the hair loss gene from your mother or your father or both (xii).

TRUE: Colouring your hair can weaken your hair

The chemicals in many hair dyes may harm your hair if you don't use them properly, and can make your hair break more easily or even cause temporary hair loss. Treating your hair more gently can help reverse the damage.

FALSE: Scalp massage can stop you going bald

It may boost your circulation, but there's no link between increased blood circulation and hair growth. The same goes for washing your hair in cold water and standing on your head neither has any effect on thinning hair.

Remedies for hair loss

There are several pharmacy and natural remedies for hair loss available, but choosing the one that will be effective for you will depend on the type of hair loss you're experiencing:


This pharmacy product for male-pattern baldness (hormone-related hair loss) is available without prescription. Minoxidil foam or lotion is available in two strengths: five percent and two percent. When applied to the scalp every day, it may slow down or reverse hair loss in some men though any improvement may not be noticeable for a couple of months. Two percent minoxidil is also available as a treatment for female-pattern hair loss in women.


If your hair loss is caused by iron-deficiency anaemia (chronic telogen effluvium), taking an iron supplement to boost your blood level of haemoglobin may help to reverse the problem with your hair. However, as some people experience constipation when taking iron tablets, it's advisable to take a form of iron that's easily absorbed, such a citrate form.

Nutrients that help increase the absorption of iron include vitamin C (xiii) and the amino acid l-lysine. Indeed, an analysis of several studies suggests 90 percent of women with hair loss are deficient in both iron and lysine (xiv)

General hair maintenance nutrients

Taking a multivitamin and mineral supplement to support overall health may also be recommended, especially if it contains nutrients approved by the EU's European Food Safety Authority (EFSA) for the maintenance of normal hair. These include biotin (vitamin B7), selenium, zinc and copper (the EFSA confirms that deficiencies in two of these nutrients selenium(xv) and zinc(xvi) may result in hair problems).

Tackling hair loss, whatever your age or gender, can be difficult, but this guide should help to make it a little easier. For more information on a variety of other common health concerns, our health library has a number of helpful articles.


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Disclaimer: The information presented by Nature's Best is for informational purposes only. It is based on scientific studies (human, animal, or in vitro), clinical experience, or traditional usage as cited in each article. The results reported may not necessarily occur in all individuals. Self-treatment is not recommended for life-threatening conditions that require medical treatment under a doctor's care. For many of the conditions discussed, treatment with prescription or over the counter medication is also available. Consult your doctor, practitioner, and/or pharmacist for any health problem and before using any supplements or before making any changes in prescribed medications.

Our Author - Christine Morgan


Christine Morgan has been a freelance health and wellbeing journalist for almost 20 years, having written for numerous publications including the Daily Mirror, S Magazine, Top Sante, Healthy, Woman & Home, Zest, Allergy, Healthy Times and Pregnancy & Birth; she has also edited several titles such as Women’ Health, Shine’s Real Health & Beauty and All About Health.

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