What is the difference between cellulose and fiber?
                                
                                
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                                    4 min read                                
                            
                                Cellulose is the most abundant organic polymer on Earth, making up the primary structure of plant cell walls. Despite this ubiquity, humans cannot digest pure cellulose, which is why it is an important component of insoluble dietary fiber. This inherent indigestibility is the key distinction in the relationship between cellulose and fiber.