Jada Pinkett Smith's history with alopecia after Chris Rock Oscars upset

Watch: Will Smith slaps Chris Rock after insensitive joke on Oscars stage

A joke made at the expense of Jada Pinkett Smith, who suffers from alopecia, became the biggest talking point at last night's Oscars 2022. Will Smith stormed the stage and appeared to hit Chris Rock after the comedian made a crass joke his wife's short haircut, comparing the shaved hairstyle of Pinkett Smith to Demi Moore's buzzcut G.I. Jane.

But the quip clearly touched a nerve with Smith after his wife had previously opened up about being diagnosed with alopecia.

Pinkett Smith, 50, has been vocal about dealing with hair loss for some time, first revealing that she was living with the autoimmune disorder publicly in 2018 on her Red Table Talk series.

"A lot of people have been asking why I've been wearing turbans. Well, I haven't talked about it. It's not easy to talk about, but I am going to talk about it," she said.

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The actor went on to say she found it "terrifying" to deal with when she first started losing her hair.

"I was in the shower one day and had just handfuls of hair in my hands and I was just like, 'Oh my God, am I going bald?'" she added.

"It was one of those times in my life where I was literally shaking in fear. That's why I cut my hair, and why I continue to cut it."

The Matrix star has also used her social media platform to open up about the subject.

Back in December she shared a video of herself to Instagram pointing out a bald line on her otherwise closely-shaven hair.

Read more: Eight-year-old with alopecia defies bullies to embrace being bald

Explaining her reasons behind drawing attention to the condition, Pinkett Smith said: “Now, at this point, I can only laugh. You all know I’ve been struggling with alopecia and just all of a sudden one day, look at this line right here. Look at that.

“Now this is going to be a little bit more difficult for me to hide so I thought I’d just share it so y’all not asking any questions.

“Mama’s gonna put some rhinestones in there, I’m going to make me a little crown.”

Watch: Jada Pinkett Smith opens up about hair loss and 'wants to be friends with alopecia’

In the accompanying caption the actor wrote: “Mama’s gonna have to take it down to the scalp so nobody thinks she got brain surgery or something. Me and this alopecia are going to be friends … period!”

Though she previously wore a head wrap when she first started experiencing hair loss, Pinkett Smith switched to a buzzcut last year after encouragement from her daughter Willow Smith.

Commenting at the time, she wrote on social media: “Willow made me do it because it was time to let go BUT … my 50s are bout to be Divinely lit with this shed.”

Read more: Woman who lost 90% of her hair is hoping to become first model with alopecia to win Miss GB

What is alopecia?

Alopecia is a health condition that causes hair to fall out.

According to Alopecia UK, Alopecia Areata is thought to be an autoimmune condition, which often starts with isolated patches of hair loss on the scalp and/or across the body including the beard, eyebrows, eyelashes or body hair, including pubic hair.

"In Alopecia Areata, cells from the immune system (a specific type of T cell, known as NKG2D+ T cells) gather around the hair follicles," the site explains. "These cells attack the follicle, stopping it from producing more hair. The exact way in which this happens is not yet understood."

Sometimes Alopecia Areata can develop into either Alopecia Totalis (hair loss across the entire scalp) or Alopecia Universalis (hair loss affecting the whole body), but in most cases the hair loss remains patchy and eventually regrowth occurs.

While the condition is often associated with stress and anxiety, it still isn't fully understood what triggers the immune system to attack healthy hair follicles when people have Alopecia Areata.

The condition can also have an impact on mental health.

“We see a lot of patients troubled by alopecia (hair loss), which can be either in patches or spread across the whole scalp described as thinning or shedding," explains Dr Abha Gulati, consultant dermatologist at Stratum Clinics.

"Alopecia areata is one of the commonest causes of patchy alopecia we see and has a huge impact on self esteem and mental wellbeing."

At the moment there is no cure for the condition, but treatments are available to slow down the loss of hair.

Common treatments for Alopecia Areata include corticosteroids (designed to dampen down the immune response) and topical immunotherapy (to distract the immune response).

"Many patients respond to treatment with topical or intralesional steroids but there is no cure so recurrence is common for some.” Dr Gulati adds.

If you are experiencing hair loss, visit Alopecia UK for advice and support.