"I have been through the mill emotionally and physically the past three weeks, cried more tears than ever, vented more frustration and at the same time calmly tried every direction and avenue available to heal myself," Radcliffe said in a statement. "As desperate as I was to be part of the amazing experience of the London Olympics, I don't want to be there below my best."
An announcement on the UK Athletics website on Sunday confirmed that a foot injury sidelined the 38-year-old, who was looking for her first Olympic medal.
"This is obviously a disappointing day for Paula and our sport, but it was important to her that if she made the start line it would be in the best possible shape," Athletics Team Leader Charles van Commenee said."It wasn't meant to be and she has taken the right decision to withdraw at this stage.
"I think it is important that we don't look at Paula's career in Olympic cycles. She is undoubtedly one of the greatest female distance runners of all times and still holds the marathon World Record.
"When we look back at her career it should be in the context of what she has achieved and not what she hasn't. I wish her all the very best for her recovery."
Previous Olympic Games have provided nothing but heartbreak for Radcliffe; she failed to finish at the 2004 Athens Olympics and placed 23rd in Beijing — where she was still recovering from a stress fracture in her thigh.
"From the day when it was announced that London had won the bid, taking part and performing well in the London Olympic Games has been a major goal in my life," Radcliffe said. "The goal of a fifth Olympics in my home country, what better? The chance to make amends to myself for bitter disappointments at the previous two Olympics."
After a world championship win in 2005, Radcliffe endured injuries to her back, hip and toe.
"However hard today is, finally closing the door on that dream, at least I can know that I truly have tried absolutely everything. Not one day was wasted in getting treatment, scans or interventions that might help," she said. "I cross-trained as hard as I could whenever I was unable to run to give myself every chance should the pain settle."Suggest a correction