Many fruits, vegetables, legumes, and seeds are good sources of fiber, including avocados, lentils, and berries. Fiber is an indigestible nutrient that's concentrated in most plant foods. High-fiber ...

Meat, cheese, yogurt, and other animal products are famously filled with protein, but the vital nutrient can turn up in plant-based places, too—and yes, there are even some high-protein grains out ...