Greater intake of dietary nitrate and green leafy vegetables is associated with a 20-30 percent lower risk of primary open-angle glaucoma (POAG), according to a study.Jae H. Kang of Brigham & Women's Hospital and Harvard Medical School, Boston, and colleagues evaluated the association between dietary nitrate intake, derived mainly from green leafy vegetables and POAG.They looked at a followup study involving 63,893 women and 41,094 men over a period of more than 35 years.During the follow-up, 1,483 incident cases of POAG were identified.
The researchers found that greater intake of dietary nitrate and green leafy vegetables was associated with a 20 percent to 30 percent lower POAG risk.The association was particularly strong (40 percent-50 percent lower risk) for POAG with early paracentral visual field loss (a subtype of POAG linked to dysfunction in blood flow autoregulation).POAG is caused by optic nerve damage that is chronic and progresses over time.The findings were published in the journal JAMA Ophthalmology.