Former President Joe Biden said he would not have run for a second term in 2024 if he had known he had cancer at the time.

Biden made the comments in an interview with People magazine ahead of the release of his White House memoir. He was diagnosed with metastatic prostate cancer months after leaving office in January 2025.

"If I had known that I was feeling lousy because I had cancer, I would’ve not gone forward" with the reelection bid, Biden said. The 83-year-old added that an 80-year-old man with cancer should not run for president.

Biden maintained he did not know about the cancer while in office and felt the June 2024 debate with Donald Trump was not a major factor in his decision to exit the race. He said he expected another debate and viewed the performance as inconsequential despite accelerating Democratic concerns over his age and fitness.

Biden withdrew weeks after the debate and endorsed Vice President Kamala Harris, who won the Democratic nomination but lost the general election to Trump.

The former president's health has faced renewed scrutiny since his diagnosis became public in May 2025. His last known PSA test occurred in 2014, according to aides. Biden has said he disclosed the diagnosis promptly upon learning of it.

The memoir and interview come as questions persist about Biden's decision to seek reelection at age 81 amid later revelations of his condition.