Actress Meryl Streep says she never touches her face to avoid spreading bacteria. Photo / Getty Images
With her youthful glow and blemish-free skin, she does not look like a woman approaching her seventies.
And although you might assume Meryl Streep's porcelain skin is the result of using expensive lotions and potions, the actress' biggest beauty secret doesn' t cost a penny.
"When she was in the Iron Lady playing Margaret Thatcher [2011], her film company decided to do something different because of that junket thing that's just so bloody tedious and everyone just goes through the motions", Miss Glover said.
"So the director had a dinner party at Meryl Streep's house where she cooked an extremely nice cauliflower curry. And Meryl was there with her daughter and obviously places were limited."
Miss Glover, who was at the party alongside Woman's Hour presenter Dame Jenni Murray, told her Fortunately podcast: "Do you know what Meryl told me that evening?
"We were talking about beauty tips, it was a fascinating evening full of political discussion and engagement.
"She said that her one beauty secret was never to touch her face. She never touches her face."
Repeatedly touching your face can spread bacteria and can cause infection, according to Dr Nicole Chiang.
The consultant dermatologist said: "I would agree with Meryl Streep's advice and I would advise people not to touch their face too much."
"When you touch your face you are transferring germs which can potentially cause infections on the face.
"And if your skin barrier function is impaired, such as with dry skin or eczema, it can allow organisms to get into the skin.
"If you have acne, touching your face can make the condition worse and picking your skin can cause spots."
Dr Chiang also warned that rubbing the skin can result in pigmentation and wrinkles.
She said: "If you're rubbing you your eyes and face, a lot of rubbing can thicken the skin and cause lines. This can cause inflammation of the skin and can affect its pigmentation."
Other celebrities who refrain from touching their faces include supermodel and it-girl Kendall Jenner, who said she was told from an early age to keep her hands away from her skin.
She said: "My sisters and my mum always told me ... to never touch your face because your hands are dirty."
Streep, who won an Oscar for her role in the Iron Lady, has opted to age naturally and has previously said she doesn't believe in plastic surgery because it 'freezes' your face.
She said in 2010: "To each his own. I really understand the chagrin that accompanies ageing, especially for a woman, but I think people look funny when they freeze their faces."