Getting enough fiber is crucial for optimal health, yet more than 90% of Americans don’t. Federal dietary guidelines recommend 25–34 grams of fiber per day for adults, depending on age and gender—but the average American adult eats only about 8 grams a day , “which is far below recommended intake regardless of age or sex,” says Dr. Michelle Hughes, medical chief of quality and safety for digestive health at Yale New Haven Health and Smilow Cancer Hospital. Advertisement Advertisement Should