I vividly remember the moment my hair began to fall out.
I was kneeling over a bath, washing it in a hotel room one Saturday evening, getting ready for my friend's 40th birthday celebration. Seventeen days earlier, I'd had the first of six chemotherapy sessions to treat my breast cancer, but days had gone by with no hair loss.
I'd convinced myself I might be one of the lucky ones.
But as I held the shower over my head, suddenly the stream of water turned dark, as long strands of brown hair began coalescing around the plug hole in front of my eyes. And there was nothing I could do to stop it.
"Oh wow," I said to myself, because I honestly hadn't expected it.
During chemotherapy, I had been wearing a cold cap – the freezing helmet designed to help preserve hair during treatment. I was told it didn't work for everyone.
It may sound dramatic, but for me, losing my hair was worse even than losing a breast through a mastectomy. Why? Because without my hair, I wasn't me. I had no idea until I started losing it that my hair was part of my identity.
Now, scientists in Japan believe they may be a step closer to changing the reality of hair loss for millions of people.
In what researchers are calling a "major breakthrough", a team, led by Prof Takashi Tsuji, say they have managed to recreate the full cycle of hair growth in mice - meaning hair could grow, fall out and grow back again naturally. While transplanted hair can already grow, recreating follicles that can behave like the natural hair inside the body - repeatedly growing, shedding and regrowing over time - has proved far more difficult.
For women living with hair loss - whether through cancer treatment, alopecia or ageing - breakthroughs like this hint at something once thought impossible: that hair loss can be reversed.
It affects millions of people worldwide, with studies suggesting around one-third of women will experience hair loss at some point in their life. So why is the emotional impact of hair loss still often underestimated and what does our reaction to losing it reveal about our identity, sense of control, and the way we see ourselves?
Across history, hair has rarely just been hair.
In Ancient Egypt, pharaohs and noblewomen wore embellished braided wigs to show power, and in the Middle Ages, women's long hair became associated with femininity and virtue. Men in the 17th century wore the "periwig" - long, voluminous artificial curls - to denote wealth and high social status. And by the 1920s, women with bobbed hair came to represent female independence and rebellion.
"Hair shapes our identity", says psychiatrist Sylvia Karasu. "It is a biological, physiological and social marker of stages of our life."
And of course it can be the first thing we notice about other people. "It's a way you can often tell gender, race and religion. It's so much tied with identity that it ends up being quite significant in terms of how we categorise people," she says.
Hair is also linked to our dignity. The forcible removal of hair has often been used to strip away identity and humanity. In German concentration camps, Jewish people had their heads shaved and their clothes replaced with prison uniforms. After France's liberation in 1944, thousands of women accused of collaborating with German occupiers had their heads shaved publicly as a form of punishment and humiliation. One of the most famous images, Robert Capa's The Shaved Woman of Chartres, shows a young mother walking through a jeering crowd with a swastika painted on her forehead.
If hair can hold so much social and emotional meaning, it seems no surprise scientists have spent years trying to understand why losing it can feel so devastating, and whether it may one day become reversible.
I've interviewed women about their relationship with their hair for my podcast with the Future Dreams charity, And Then Came Breast Cancer. Again and again, women told me the same thing: it was nothing to do with being vain.
Nicky Elkington, a hairdresser, told me she was determined not to lose her hair when going through chemotherapy. "It's not a vanity thing… and I think people think that, but it's your identity and I didn't want to look like I had cancer," she says.
For her, the worst thing anyone could say to her was, "It's only hair, don't worry about it".
School nurse and mother of two, Natasha Anderson, said she loved messing about with her hair while growing up - "one week having a big afro, then having hair extensions," she remembers.
"It wasn't just hair, it was my culture."
Faced with the prospect of losing it through chemotherapy, she asked her brother to shave it off for her.
"I felt liberated when it was being shaved," she says. "I had taken control of the situation… it was more painful and upsetting seeing it just falling out."
One of the hardest parts of cancer is how little control you have over any of it - the diagnosis, treatment, or the side effects. For some women, choosing to shave their hair before it falls out becomes a way of taking back a semblance of control in their life.
What surprised me during my treatment was how often concern about hair loss was dismissed as superficial.
"Why are you worried about your hair? You're alive." It's a legitimate question. And yes, I was lucky to survive. But surviving illness and grieving the loss of part of your identity are not mutually exclusive things.
As Sylvia Karasu told me, losing your hair for a lot of us is a "marker of being a sick person".
Between 50% to 75% of my hair fell out during chemotherapy.
It was unbelievably dispiriting. I remember sitting in a wig salon in Richmond as the owner, Amy Holt, gently brushed though my tangled hair as it was falling out in large lumps. I just cried.
According to Diane Trusson, a medical researcher at the University of Nottingham, hair loss on top of a diagnosis is "a double whammy".
"You've been told you've got cancer and then you start the treatment and then you've got this brutal thing to happen and it changes the way people see you. It's just that extra thing to deal with on top of having surgery and quite horrible treatments."
For me, getting a wig was important. I could carry on presenting a daily TV news programme. I didn't want viewers to be distracted from the stories we were covering by me either having a bald head, or wearing a scarf. A wig was the best option.
Amy made one for me with real hair sourced from women who donated or sold it. Seeing the wig for the first time felt surreal.
It looked so much like my own hair: the colour, cut, length. In my head there was disbelief, and my emotions were volatile – one moment in tears, the next elated because it was going to allow me to go about my daily routine.
Yet still, scientists don't fully understand the biology of hair loss.
According to Claire Higgins, a professor of tissue engineering at Imperial College London, studies into hair loss have struggled for many years to get funding and attention, particularly when it comes to women.
"The women side is definitely under researched", she says.
She says much of the work has focused on male hair loss, partly because men are more likely to get hair transplant surgery, which has made scalp samples easier to access for scientists.
"Men and women are often tackled the same because people assume it is the same, but I don't think it should be," she says.
She points to large genetic studies into male male pattern hair loss - typically characterised by a receding hairline and thinning at the crown - known as genome-wide association studies, which identified several genes linked to the condition. But all were done on men.
More recently, researchers in Germany have investigated the genetics of female pattern hair loss, which typically involves hair loss at the top of the head. Scientists expected to find at least some overlap in the genes involved.
"But there wasn't," Higgins says. The findings showed that male and female hair loss may be caused by different things (though scientists still aren't totally sure what those causes are).
"We know cells are lost in the follicles but we don't know if they die or just migrate away. We know very little about the mechanism of why [hair loss] occurs."
That's why the work of Prof Tsuji in Japan is important. He and his team think they have found a missing piece of the puzzle.
For a long time, scientists believed there were two key types of cells responsible for growing hair: epithelial stem cells, which create the hair follicle in the first place, and dermal papilla cells, which tell the hair when to grow.
Those cells cannot grow hair in a lab, only when they are transplanted into skin and connected with underlying tissue.
But Tsuji says his study identified a "novel third cell type", called a hair follicle regenerative-supporting cell.
And crucially, the new cell could bring scientists a step closer to the possibility of growing hair in a lab.
"In simple terms," Tsuji says, "our study identified a [cell] which supports the development, growth and regeneration of hair follicles."
Tsuji says the findings are "a major breakthrough", a potential game-changer in treating alopecia.
Claire Higgins, who was not involved with the study, agrees it is significant. She says previous research has only managed to create partial hair follicles in the lab.
"No one had managed to get fully cycling hair follicles like this before," she says. "That's a really big step." In other words, the follicles were able to repeatedly grow, shed and regrow hair in the way natural hair does.
The study was only carried out on mice, mostly via cells taken from their whiskers. Translating the findings so they can be used on people remains difficult because human hair growth is far more complex.
Still, Tsuji is hopeful. "We believe we are now much closer than before."
Last year, I saw a post from someone on social media which featured a close-up photo of Catherine, Princess of Wales at an event. The words simply read, "that's a bad wig". I found it particularly cruel and upsetting.
None of us knows what cancer treatment she underwent, whether she lost her hair, or whether she wore a wig at all. If someone had said that about me during chemotherapy, I would probably have wanted to hide indoors.
Indeed, hair loss through illness is not something anyone would choose. It's imposed upon us and that's why it was so hard, for me at least, to come to terms with.
And that matters, because hair is never really just hair.
For many of us, it is our identity, our privacy, our way of feeling in control and feeling confident. So forgive me when I say that's why hair matters so much.
Top image credit: Getty Images
Additional reporting: Florence Freeman
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