Analysis of data from the Nurses' Health Study published online in the January 14 edition of JAMA found that consuming a diet high in green leafy vegetables resulted in a 21% lower risk for primary open-angle glaucoma (POAG). Nitrates are naturally found in relatively high amounts in green leafy vegetables, but also in other vegetables such as beets and carrots. Nitrates are converted to nitric oxide (NO) in the body. NO is important for optimal blood flow, which may play a role in glaucoma. As an aside NO is important for healthy arteries. Hypertensive people would also be well-served by eating lots of green leafy vegetables, beets, and carrots.