Food Safety Report: Natural Grocers, 3165 Central Park Blvd, Denver, CO 80238, USA 2 years ago • details 6 Comments Comment Suspected food poisoning. Symptoms: Diarrhea, Vomiting, Chills Suspected source: Blue cheese or endive Onset: 4 to 12 hours Duration: 12 to 24 hours Sick: 3 people Additional information: One person with symptoms is 5 months pregnant