Adele suffers from 'Impostor Syndrome' - what is it, and how do you overcome it?

Watch: Adele breaks down in tears as she is reunited with her old English teacher

Adele shone in her special homecoming concert, to celebrate her new album, 30. The star sang hits to a hand-picked audience of celebrities and key workers, including her 'inspirational' teacher, and chatted openly to the audience in answer to their questions, admitting that her tights were falling down, and that she had been "s***ing herself" with fright about her ability to perform.

But she revealed the most when she answered a question about when she had felt proud of herself. She told the audience that it was when she agreed to headline at Glastonbury, despite being terrified. She added: "Because I've got Impostor Syndrome."

It may be hard to believe that the multi-millionaire global star suffers from feelings of inadequacy, but 'Impostor Syndrome' can strike anyone.

It was originally recognised in women, particularly high-achieving ones. The term was first used in 1978, to describe the feelings of some of the women entering traditionally male-dominated professions such as banking or science.

The phrase was coined by psychologists Suzanna Imes and Pauline Rose Clance, who detailed the 'coping' and 'protective' mechanisms used by people suffering from Impostor Syndrome. They included over-preparing for meetings and presentations, procrastination, fear of applying for promotion and shyness about speaking up in meetings. According to mental health experts, it's also linked with perfectionism and can lead to stress, anxiety, low self-confidence, and low motivation.

It's been more openly spoken about in recent years, as our focus has turned to mental health. It's now understood that it can affect anyone, regardless of sex, status or skill level and experience.

According to Dr. Valerie Young, an internationally-renowned expert on impostor syndrome and author of The Secret Thoughts of Successful Women: Why Capable People Suffer from the Impostor Syndrome and How to Thrive in Spite of It:

"Impostor syndrome describes a difficulty in internalising one's accomplishments or abilities, and instead attributing their success to other factors. Factors such as luck, timing, 'someone helped me', 'I had connections' are common examples," she recently told recruitment organisation Stem Women.

"Sometimes people plant the seed in our mind that perhaps we are only here because we were a diversity pick in some way, for example, 'They were looking for a woman', or 'I'm included to increase the racial diversity'. We externalise our success, and we are left with a fear of being found out."

Read more: Dave Gahan has impostor syndrome

Health organisation BUPA explains the signs include, "feeling like a fake or a fraud" and that you:

• never feel good enough

• feel like you don’t belong

• are filled with self-doubt

• feel uncomfortable when people praise you

• have a habit of playing down your strengths

• find it hard to take credit for your accomplishments

So if that all rings an enormous, impostor-shaped bell, no matter how well you do at work, what can you do to overcome the feelings that are holding you back or getting in the way of allowing you to celebrate your success?

Olivia James is a Harley Street therapist specialising in performance and confidence. She tells Yahoo,

"Imposter Syndrome is the feeling that it’s only a matter of time before you’re 'found out'. That you don’t deserve your position, job, acclaim, awards and salary. There’s been a big mistake. Essentially, it’s a self-worth issue."

She goes on: "When we hear an accomplished celebrity admit they feel like an imposter it can land in two ways: We can feel better because even Adele, Michelle Obama, Meryl Streep and author Neil Gaiman - who have all talked about this - sometimes feel like their success has been a fluke.

Read more: How To Overcome Imposter Syndrome

"We can also feel worse because if they feel like that, what hope do we mere mortals have?"

Sometimes, she adds, we may struggle to believe it.

"Depending on the celebrity, it can also strike us as totally unfathomable and frankly like fake vulnerability. Vulnerability is very fashionable.

"Pauline Clance, the psychologist who coined the term now wishes she’d called it the Imposter Experience," adds James. "She said, 'if I could do it all over again, I wouldn't call it the Impostor Syndrome, because it's not a syndrome or a complex or a mental illness. It's something almost everyone experiences."

Olivia James agrees. "Calling it a syndrome pathologises it and seems to make it more like a permanent affliction or “disorder”, but most people have the occasional 'imposter moment'."

Despite popular belief that women are more likely to report 'impostor syndrome', James adds, "It's a total fallacy that women suffer more. Imposter syndrome is an almost universal experience.

"I see just as many men as women with this issue in my clinic. It's (just that) it's more socially acceptable for women to admit they have imposter syndrome. Women are more likely to publicly admit they have it and are often are blamed for the lack of gender equality, the gender pay gap, the lack of female leaders in boardrooms - 'women should be more ambitious and confident'.

Reality is a lot more complex than that."

Watch: Why Impostor Syndrome gets worse when working remotely

How to deal with imposter syndrome

Olivia James says:

"The more stressed we are, the more our minds can spin out of control. I teach my clients calming techniques and we deal with the causes of their insecurity.

"The key is to determine whether your concerns are based on facts.

Is it objectively true that your skillset doesn't match what's required? Is it objectively true that you don’t belong and you are a fraud?

"Imposter syndrome is trying to keep you safe, it's trying to stop you from making a fool of yourself. The trick is to determine whether your feelings are based on reality. What is your skill set, what experience and qualifications do you have? There's a huge difference between feeling nervous and being completely out of your depth.

"The problem is that performance anxiety and confidence issues often aren't rational. When your nervous system is in fight-flight it prioritises safety and survival.

"In this acute stress state, your rational brain is not fully accessible. (Most of the blood goes to your vital organs and arms and legs in case you are coming under attack and need to fight or run.)

The trick is to calm your nervous system response and remind yourself you DO know what you're doing and you DO belong."

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