Fans have been excited about the home cook joining the Channel Seven program this year alongside Manu Feildel after controversial chef Pete Evans was axed from the show.
In light of her appearing on the program, fans have taken to Twitter to express their shock over Nigella's age-defying looks.
Many were floored to learn the cook is 62 years old, with many saying she looked 20 years younger.
"Can someone explain to me how Nigella Lawson can look so stunning ALL THE TIME?" one said.
"She's 62 and looks 42. What kind of witchcraft is she performing!"
Another said: "Nigella Lawson is 62 years old??? Holy moley!! I don't trust my own Google search."
"There is no way Nigella Lawson is 62," a third added.
"I thought this woman was in her 40s," somebody else commented.
In an interview with Good Housekeeping in 2020, Nigella revealed she doesn't dwell on her age.
"My mother died at 48 and my sister at 32. And then John [her late husband] at 47. So, even if I were the sort of person who planned ahead, I don’t think I would have seen myself here… I kind of think you can’t do anything about [ageing] so why complain?" she said.
MasterChef stuns fans with real age
"No way! If you said 27, I would’ve believed you!" one fan said.
"Sorry I think you had a typo; you mean 37 right?!" another commented.
"You are so eternally youthful Poh," a third added.
The now 49-year-old told Yahoo Lifestyle that she found it both funny and flattering people were surprised by her age before revealing her secret.
"I live a really vibrant life," she said. "And I fight really hard for it."
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