Loose Women host Janet Street-Porter says she was even grumpier when she began her TV career – until Sir Elton John told her she was being “a nightmare”.

And the notoriously outspoken broadcaster, who has been friends with the Rocket Man singer for more than four decades, has revealed she changed her ways after his intervention.

“When I was in my 40s and I was really a whingey cow, Elton wrote me a letter and told me I was absolutely a nightmare, and I had to lighten up,” said Janet. “And I think I took that on board. I stopped moaning.”

Speaking on Loose Women: The Podcast, the 78-year-old added: “I’ve had other people tell me, ‘you crossed the line, you said too much’.

“But I probably do it less now than I used to. That makes everyone feel a little bit happier and more comfortable.”

Janet, first met Sir Elton, also 78, when she was in her 30s. She was at his first wedding to German recording engineer Renate Blauel in 1984 and made the speech at his civil partnership to David Furnish in 2005. When she ran out of money while refurbishing her house, Sir Elton ripped out his own purple kitchen and gave it to her. More recently he has confided in her about his health woes, after losing sight in his right eye after an infection.

But broadcasting veteran Janet admitted that even despite his warning, her straight-talking has still got her “into trouble on numerous occasions”.

She said: “I can’t stop myself. If something’s rubbish I just say it. But I realise now in modern society you can’t criticise. You have to do constructive criticism. What a waste of time that is.

“We live in an age where everybody spends far too much time worrying about hurting other people’s feelings. It’s exhausting.”

Janet began her career as a fashion writer in the 1960s, before moving into TV. She has been a regular panellist on the ITV lunchtime talk show since 2011. Married four times, she is known for speaking her mind. Most recently she had a heated row with fellow panellist Denise Welch, 66, branding her “selfish” during a debate on immigration.

She has also clashed with Katie Price in a discussion about lip fillers, with Penny Lancaster over prison sentences and with Davina McCall about fitness. But Janet revealed that despite her tough appearance, she was actually scared about joining Loose Women.

“I had to be persuaded because I found it very intimidating to go into a room with a group of women who had worked together for many years.”

She also insisted that when she’s not on screen she’s actually quite shy: “The misconception is that I’m a kind of brash extrovert, who likes making noise. But the truth is there are two Janets. There’s a Janet that’s on TV. And there’s the real Janet, which is shy – don’t like meeting new people, very cautious about making a friend, don’t like change.”