Fleabag said it, and many believe it: hair is everything. Whether or not that's true, we cannot deny that hair, more than all other features of our bodies, is inextricably linked to our identities.

For centuries, it's been one of the key metrics by which society measures femininity, fertility and youthfulness in women and virility and strength in men.

Now in 2022, the landscape of fashion and self-expression has changed dramatically, and one's hair or lack thereof doesn't have to be the yardstick by which we measure beauty.

Going bald, shaving our heads, getting mohawks or wearing hats; there are many ways to express ourselves that don't involve having and maintaining long locks. But, this doesn't mean it can't be deeply upsetting, disconcerting and confusing when we start noticing hair loss, especially when we're in our 20s.

You might notice clumps of hair coming out in your hair brush, losing hair on your pillow after a night's sleep, or larger than usual amounts of hair clogging your shower drain. Maybe you're now seeing noticeable hair loss after wearing a tight ponytail for a few days.

You also might be aware that the top of your scalp starting to show, with hair disappearing along the middle of your head. Changes in your hair can be difficult for your self-esteem, driving you to style, straighten, curl, bleach, darken or cut it back into submission.

If hair is "everything", then premature thinning and shedding can be devastating for women who take pride in their tresses. Watching your hair fall out in your 20s, long before menopause, feels like a raw deal.

We believe all heads are beautiful and worthy of high-quality care, so naturally, we're interested in understanding the causes and treatments of female hair loss.

What is considered to be normal hair loss?

On average, we lose roughly 50-150 hairs a day [1]. Now, we don't expect anyone to sit down and count out the hairs on their pillow every morning. But, you know your body more than anyone else, and hair loss is extremely individual.

If you feel like you are losing more than 50-150 strands of hair a day and your hair density is decreasing, then this is outside the normal level and needs to be investigated.

Before you think about how to treat hair loss, it's important to understand the cause.

Certain medical conditions and medications can cause hair loss, as well as poor mental health, poor diet, vitamin deficiencies and even stress.

How do I tell if my hair is shedding or thinning?

Thinning

If you are experiencing hair thinning, the hair across your scalp will become diffuse and you will start to be able to see your scalp [2]. This will happen slowly and in stages.

Hair thinning across the scalp is a sure sign of female pattern baldness and is also known as androgenic or androgenetic alopecia. Normally, it appears in the later years of our lives: women usually start to notice thinning hair after menopause.

Women who have androgenic alopecia will rarely go completely bald and won't experience a receding hairline, which makes it quite different to male pattern baldness. Rather, it starts in the middle of the part and spreads.

Shedding

Hair shedding or hair fallout is triggered as a result of a shock to the body [3].

Unlike pattern baldness which is thinning hair across the scalp, hair shedding is when you notice that you quite literally have less hair — you will have more hairs in your hairbrush or on your pillow in the morning than you usually do.

Excessive shedding is also known as telogen effluvium. Luckily, this kind of hair loss in females is temporary and usually sorts itself out on its own after the cause is identified and treated.

What are the causes of female hair loss?

Excessive shedding or thinning of hair can occur for a number of environmental, physical and even mental factors.

Healthy hair growth is characterised by 3 different stages:

1. The anagen stage: where hair is growing;
2. The catagen stage: where hair stops growing; and
3. The telogen stage: where you shed dead hair. This is also known as the "resting" phase [4].

This healthy hair cycle is a long-term process with the growth stage lasting for 1-3 years, the resting stage just a few months and the shedding stage completed within days or weeks.

On a healthy scalp, up to 95% of your hair will be in the anagen or growth phase and only 5% should be shedding [5]. If it's more than 5%, it may be due to the following common causes.

Hormonal imbalances

Those pesky hormones and their imbalances are the cause of female pattern baldness. Androgenetic alopecia refers to our androgens, which are an essential hormone in male sexual development and hold important functions for females too.

Androgenic alopecia is characterised by the loss of hair along the line of the part first. An androgen increase can be caused by:

• Taking a combined contraceptive pill, or other contraceptives (including the Mirena IUD), with a high androgen index [6].
• A diagnosis of polycystic ovary syndrome. PCOS is a condition in which the ovaries start producing higher than necessary androgens in the body and can cause irregular periods, acne and even excess body hair (e.g. on the face, arms, legs etc.) [7]. PCOS accounts for around 70% of cases of hyperandrogenism [8].
• Other androgen-heightening health issues (e.g. Cushing's disease).
• A genetic predisposition to androgen sensitivity.

And just to further blame our hormones, telogen effluvium can also occur thanks to a hormonal shift that shocks the body, such as going on or coming off birth control.

Hypothyroidism can also be a hair loss culprit: if your thyroid is underactive, metabolism slows down, and the lesser important body functions like hair and skin suffer first.

Genetics

It looks like you can blame your parents for something! Androgenic alopecia can be a hereditary condition [9]. Female pattern baldness can come from either the maternal or paternal side.

Giving birth

After pregnancy, you may notice more hairs on your pillow, in your hairbrush or in your shower drain than you did while pregnant. Some hair loss after giving birth is normal, but once again, it all comes back to hormones.

Estrogen levels will plummet once the baby is out, and having high estrogen levels is what's responsible for our shiny, healthy skin, hair and nails during pregnancy.

The unruly hormonal swings going on in the bodies of postpartum women will cause more strands of hair than usual to enter the resting stage, and then fall out a few weeks later.

Stress

Yes, there is a stress-tress connection. And we get it: if you're experiencing high levels of stress, the last thing you probably want to be dealing with is hair loss. Unfortunately, stress-related hair loss is another common reason for hair to fall out and comes under the telogen effluvium umbrella.

Major stress hormones push hair follicles into their resting phase, stopping them from regenerating and moving back into the anagen phase as a way of preserving energy [10].

"Stress" can also refer to a traumatic event that occurs in the body, including childbirth, excessive weight loss or a bout of illness.

Autoimmune disease

One of the most common culprits behind hair loss, especially when it happens before age 50, is an autoimmune disease [11]. With these types of conditions, your immune system mistakenly attacks parts of the body including hair follicles.

People with autoimmune conditions will be all too familiar with excessive thinning, shedding or even small bald patches that appear on different parts of the head.

Alopecia areata is a common autoimmune disorder that can cause hair loss of varying levels:

• Alopecia areata "patchy": The most common form, with one or more 20-cent piece-sized patches on the scalp or other areas of the body
• Alopecia totalis: The total loss of hair on the scalp
• Alopecia universalis: The complete loss of hair on the scalp, face and body

It's important to get checked out by your GP if you believe you might be experiencing an autoimmune disease.

Vitamin deficiency

In general, vitamin deficiencies can cause a range of health problems if they go unaddressed.

Vitamin D, iron, zinc, vitamin A, vitamin B7, vitamin F and vitamin E deficiencies are all linked to unhealthy hair follicles and subsequent hair loss in both men and women [12].

How can I prevent hair loss in my 20s?

No one likes the idea of losing their hair, and that's especially true for those under 60.

But if you already know you're sensitive to androgens, or if you have recently been diagnosed with an autoimmune condition, or if female pattern baldness already runs in your family, then you have knowledge on your side: you can start to take steps in preventing hair loss.

Hair loss prevention is certainly achievable. Some of the actions you can take now to preserve flowing hair are:

Maintaining a balanced diet

Keep up with all the right vitamin and mineral levels to help premature hair loss.

Nutritional deficiencies are very preventable when you're equipped with the right knowledge of the right foods to eat to keep your hair at a normal level.

Avoid extreme dieting

Losing an excessive amount of weight in a small amount of time is one of the common stressors that can trigger hair loss in females.

Stopping smoking

Smoking has so many negative health effects and our hair follicles are no exception.

Smoking inhibits blood flow to the scalp, causes oxidative stress, depletes collagen (leaving hair dehydrated and damaged) and raises our cortisol levels, which can lead to stress-related hair loss.

Avoiding a tight ponytail

Tying your hair every day in a tight ponytail, braid or bun can pull on the hair follicle. Doing this repeatedly will damage and eventually break your hair follicles, starting at the hairline.

Using hair extensions or weaves can also put stress on the hair follicles, as will using too much heat.

Not over-washing or under-washing

Use good-quality cleansing products for your hair type, keep the water warm (not hot), clear away dried skin, dead hair and other dirt, and be gentle with your hair and scalp.

This will ensure that your scalp and hair follicles are at their healthiest, promoting healthy hair follicles and therefore, healthy hair growth. Massaging your scalp can also help increase blood flow, improving hair health overall.

Taking time out to manage stress

Treating stress on the body and mind also means treating hair loss. Stress-related hair loss can be prevented by listening to your body, noticing when you are stressed, what those triggers are and learning how to cope.

There will be times when telogen effluvium will occur as a result of stress and there won't be much you can do about it, like after giving birth.

But if you are losing hair thanks to consistently rising stress hormones, you should speak to your GP about how to manage ongoing stress.

How can I stop losing my hair in my 20s?

Sometimes, we cannot prevent hair loss no matter how old we are — even if we're perfectly healthy. This is especially true if you live with an autoimmune disease or if you are genetically predisposed to alopecia — some of us, even those of us in our 20s, might end up with temporary hair loss or long-term baldness.

But, there is a range of highly effective medications that can help combat thinning hair — consider talking to your doctor about your concerns and they'll be able to help you find the right treatment for you.

Can hair grow back after thinning?

It depends! Female pattern baldness often responds well to medications, and there is a wide range of treatment options to help promote hair regrowth including light therapy and even plasma injections.

If you have a history of androgenetic alopecia or thinning hair, you should make an appointment with your dermatologist and discuss the best prevention or treatment methods.

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