Bilberry Leaves, 1 lb. Bilberry is often said to improve night vision, and the story is told of RAF pilots in World War II using bilberry for that purpose. A recent study by the U.S. Navy found no effect, however, and the origins of the RAF story are unclear; it does not appear to be well known in the RAF itself. Studies have shown that bilberry can reduce or reverse effects of degenerative eye disorders such as macular degeneration. The overall therapeutic use of bilberry is still clinically unproven. It may have other beneficial effects on capillaries due to the strong antioxidant properties of its anthocyanidin flavonoids. The leaves have historically been used to treat gastrointestinal ailments, applied topically or made into infusions. The effects claimed have not been reproduced in the laboratory, however. Billberries were also collected at Lughnassadh, the first traditional harvest festival of the year, as celebrated by the Gaelic people. The crop of billberries was said to indicate how well the rest of the crops would fare in their harvests later in the year.