To assess whether dietary habits can be associated with the presence of primary open angle glaucoma (POAG), while taking into account hereditary factors and metabolic disease. A case-control study of 100 POAG patients and 100 controls who were queried on their dietary habits. A nonlinear canonical correlation analysis is employed to assess and plot the relationships between the measured variables. Controls had lower consumption of sweets containing processed sugar and avoided eating visible fat on their meat or meat sausages (which tend to contain high amounts of meat fats not plainly obvious) while consuming pure fruit juice and pears more frequently. Dietary habits and practices may have both research and clinical significance in POAG; Caffeine, processed sugar and animal fat appear to have noteworthy negative effects and while caffeine has been researched extensively, more research is needed in the negative role of the other two factors. Other important dietary factors that may be implicated is fruit fiber and various fruit antioxidants and flavonoids.