January is National Glaucoma Awareness month
In The News:
A Recent Study Suggests Glaucoma May Be an Autoimmune Disorder
A new study from MIT and Massachusetts Eye and Ear has found that glaucoma may in fact be an autoimmune disorder. In a study of mice, the researchers showed that the body’s own T cells are responsible for the progressive retinal degeneration seen in glaucoma. Furthermore, these T cells appear to be primed to attack retinal neurons as the result of previous interactions with bacteria that normally live in our body.
Nutritional Guidance for Glaucoma and other diseases:
The Physicians Committee for Responsible Medicine PCRM’s Nutrition Guide for Clinicians provides free, expert, evidenced based support to healthcare professionals. The guide can be found at www.nutritionguide.pcrm.org
The following nutritional considerations for glaucoma are from the PCRM.
Nutritional Considerations For Glaucoma
Metabolic syndrome, obesity, blood pressure abnormalities, and diabetes are risk factors for POAG.[1] A diet that helps maintain normal blood pressure and blood glucose concentrations may help reduce the risk for this disease, although no controlled trials have investigated this possibility.
Nitrate-rich leafy greens. A large prospective study showed that a greater intake of nitrates from green leafy vegetables was associated with 20% to 30% lower risk of POAG.[2] Dietary nitrates
increase Nitric Oxide (NO) production via the ‘nitrate- nitrite- NO’ pathway.[3] Nitric oxide has
emerged as a POAG therapeutic target, as it may help to regulate intraocular pressure. The endogenous NO pathway may be compromised in POAG and dietary nitrates from leafy greens offer an alternative pathway to increase NO production.[2]
Antioxidant-rich fruits and vegetables. A study with 584 African-American women found that those who consumed 3 or more servings of fruit or fruit juice per day were 79% less likely to have glaucoma than those who consumed less than one serving. Fruits and vegetables high in vitamins A and C and carotenoids were especially protective.[4]
The Rotterdam Study, including 3500 participants aged 55 years and older, showed that those with a higher retinol intake had half the risk of POAG compared to those with the lowest intakes.[5] The benefits come from food sources; supplemental antioxidant vitamins do not appear to be beneficial.[6] More evidence is needed before specific recommendations can be made.
Studies have noted an association between obesity and both intraocular pressure and ocular hypertension.[7] ,[8] The links between obesity and intraocular pressure have been thought to be the result of excessive intraorbital adipose tissue, increased blood viscosity and episcleral venous pressure, and impairment of aqueous outflow.[7] Evidence does not yet indicate that losing excess weight reduces the risk for glaucoma, although significant decreases in intraocular pressure have been reported in humans during weight loss (0.4 kg- 1.5 kg)[9] and reduced waist circumference[10] associated with fasting.
References:

1. Davis BM et al: Glaucoma: the retina and beyond. Acta Neuropathol 132:807, 2016 [PMID:27544758]
2. Kang JH et al: Association of Dietary Nitrate Intake With Primary Open-Angle Glaucoma: A Prospective Analysis From the Nurses' Health Study and Health Professionals Follow-up Study. JAMA Ophthalmol 134:294, 2016 [PMID:26767881]
3. Lidder S, Webb AJ: Vascular effects of dietary nitrate (as found in green leafy vegetables and beetroot) via the nitrate-nitrite-nitric oxide pathway. Br J Clin Pharmacol 75:677, 2013 [PMID:22882425]
4. Giaconi JA et al: The association of consumption of fruits/vegetables with decreased risk of glaucoma among older African-American women in the study of osteoporotic fractures. Am J Ophthalmol 154:635, 2012 [PMID:22818906]
5. Ramdas WD et al: Nutrient intake and risk of open-angle glaucoma: the Rotterdam Study. Eur J Epidemiol 27:385, 2012 [PMID:22461101]
6. Bussel II, Aref AA: Dietary factors and the risk of glaucoma: a review. Ther Adv Chronic Dis 5:188, 2014 [PMID:24982753]
7. Cheung N, Wong TY: Obesity and eye diseases. Surv Ophthalmol 52:180, 2007 Mar-Apr
[PMID:17355856]
8. Wang S et al: Major eye diseases and risk factors associated with systemic hypertension in an adult Chinese population: the Beijing Eye Study. Ophthalmology 116:2373, 2009 [PMID:19815279]
9. Dadeya S et al: Effect of religious fasting on intra-ocular pressure. Eye (Lond) 16:463, 2002 [PMID:12101455]
10. Hassan MB, Isawumi MA: Effects of fasting on intraocular pressure in a black population. Middle East Afr J Ophthalmol 21:328, 2014 Oct-Dec [PMID:25371639]