This is not necessarily the most popular among foods that offer plentiful fiber, but it certainly is a good one. Barley is a grain most often associated with cereal and it is highly popular with its association with beer, although there is no fiber in beer. A one-third cup of barley offers a whopping 42 percent of your daily fiber requirements, making this one of the best and healthiest of options to increase your fiber intake. Find this whole grain option in your grocery store in the natural foods section and consider having a serving every day for best results. You can also supplement your barley intake with the consumption of cereal, but usually there are small amounts with each cereal serving.