updated 09/08/2012 AT 11:00 AM ET
•originally published 09/08/2012 AT 11:50 AM ET
“When my father was diagnosed with cancer, it really changed the way that I lived – it changed my whole lifestyle,” Paltrow, who executive produced the multi-network Stand Up to Cancer broadcast Friday night, tells PEOPLE.
“I completely changed my diet, and I got very serious about exercising and about exposure to toxins.”
“It really changed the way that I thought,” says the actress, 39. “I think I had more of a laissez-faire attitude about my health, and when he got cancer it was a real shock. … It was sort of like the break of my adolescence.”
“This is my one life, and I need to invest in myself and my family and make sure that we can do what we can to stay healthy,” she added.
Remembering her father – who produced television series like St. Elsewhere and directed his daughter in the 2000 film Duets – by producing the Stand Up to Cancer show turned out to be an emotional experience for both Paltrow and her mother, actress Blythe Danner.
“It’s emotional for me because I keep getting emails from my mother saying how proud she is of me that I’m doing it, and she keeps talking about my father, Paltrow, whose husband Chris Martin and his band Coldplay also participated in the event, told reporters.
“It’s emotional to be in front of the cameras and encouraging people to join the fight against cancer,” she said. “Especially when you’re doing it in memory of someone that you loved so much.”