(CNN) -- The California runner who was lost in a forest for three days without water had barely a few hours to go before she would have died, her doctor said Thursday. Runner Maria "Gina" Natero-Armenta, 36, survived for three days without water in a California forest. Maria "Gina" Natero-Armento, 36, not only survived 72 hours with only a slice of apple in her stomach and a little bit of water for nourishment, she also has only one functioning kidney, Dr. Derrick Hong said. He spoke with CNN on Thursday afternoon, along with Natero-Armento and her husband, Armando Armento, in a conference call interview from her room at Mission Hospital in Mission Viejo, California.
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Maria "Gina" Natero-Armento, 36, had no food or water for days
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She and her running partner say they got lost in Cleveland National Forest
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She was found in a ravine Wednesday by a rescue helicopter
She didn't bring food with her, but @placeholder said she ate a piece of apple before she started, and that was the only food in her stomach.
And @placeholder said she also made another, more serious bad decision.