Acorn, or oaknut, is the nut of the oaks and their close relatives. It usually contains a single seed, enclosed in a touch,leathery shell.and borne in a cup-shaped cupule. Acorns served an important role in early human history and were a source of food for many cultures around the world. Raw acorns are considered unsafe due to their tannins, which are toxic if consumed in high amounts. However, you can remove the tannins by boiling or soaking. Properly prepared acorns are perfectly edible and full of nutrients like iron and manganese. Delicious roasted, they can also be ground into flour. Acorns are a great source of fiber, which nourishes your beneficial gut bacteria. Additionally, acorns have long been used as an herbal remedy to treat stomach pain, bloating, nausea, diarrhea, and other common digestive complaints.