There is growing evidence of metabolic deficiencies and defects playing a crucial role in causing glaucoma.
Certain genes, such as ATP binding cassette subfamily A member 1 and phosphomannomutase 2, are involved in carbohydrate and lipid metabolism/anabolism. These genes are expressed in the retina and optic nerve, where functional disruptions to the retinal ganglion cells (RGCs) and their networks have been identified in glaucoma. Variations in the aforementioned genes could contribute to development of glaucoma.
A genome-wide association study of normal-tension glaucoma (NTG) in Japan reported strong associations with elongase of very-long fatty acid 5 (ELOVL5), a gene involved in lipid metabolism pathways.
Researchers have found that serum cholesterol and triglycerides are closely associated with primary open-angle glaucoma (POAG). They hypothesize the role of hypertriglyceridaemia in causing vascular dysfunction, ischaemia and RGC degeneration.
Complementary and alternative medicine (CAM) has been explored as a means to preserve or regain the visual health of patients with glaucoma.
CAM is holistic in approach, and includes diet, exercise and general health measures. ‘Complementary’ interventions are those that are added to conventional therapy, while ‘alternative’ interventions are used in place of conventional treatment. ‘Dietary supplements’ provide nutrients, while ‘food supplements’ are concentrated sources providing nutrients.
In patients with glaucoma, CAM aims to address both IOP-dependent and IOP-independent factors in the development of glaucoma. A study from Canada revealed that nearly one in nine patients with glaucoma use some form of CAM treatment, while a study from India reported that 5–10% of patients with glaucoma use CAM.
Dietary agents that are useful in managing glaucoma include antioxidants, ginkgo biloba, saffron, peaches, egg plants and, possibly, tea. Conversely, certain foods are probably best avoided by patients with glaucoma, such as alcohol in large measures, coffee and foods that acutely increase blood pressure (BP).
Our review, published in touchREVIEWS in Ophthalmology. 2022;16(1):22–9, analyzes how different diets can be useful or detrimental to the visual health of patients with glaucoma. It also aims to shed light on the effect of dietary intervention on the epidemiology of glaucoma.
