2005

J Fr Ophtalmol. 2005 Mar;28(3):312-6.
[Hypothesis on the role of nutritional factors in ocular hypertension and glaucoma]. [Article in French].
Desmettre T, Rouland JF.
Centre d'Imagerie, Laser, et Readaptation Basse Vision, Lambersart.

Recent notions in connection with oxidative stress and the fat balance of long chain polyunsaturated fatty acids (PUFA) families have brought new insight to a probable role of nutritional factors in glaucoma and intraocular hypertony. The modifications of the extracellular matrix of the trabecula could be influenced by oxidative stress. On the one hand, collagen apoptosis and remodeling (associated with an increase in intraocular pressure) are mainly influenced by hydrosoluble antioxidants such as glutathione. On the other hand, elastin apoptosis and remodeling (correlated with the occurrence of optic atrophy) are particularly influenced by liposoluble antioxidants such as vitamin E. In addition, the dietary ratio of omega3/omega6PUFA intake could influence the balance of intraocular pressure. Omega-3 PUFA could influence cyclooxygenase competition. A diet with increased omega-3 and decreased omega-6 could thus favor an increase in intraocular pressure reducing synthesis of PG-F2, leading to a decrease in uveoscleral outflow. The true importance of these factors has not yet been solidly determined and studies are in progress to clarify the real implication of these nutritional factors.

Arch Ophthalmol. 2005 Apr;123(4):517-26.
Long-term nutrient intake and 5-year change in nuclear lens opacities.
Jacques PF, Taylor A, Moeller S, Hankinson SE, Rogers G, Tung W, Ludovico J, Willett WC, Chylack LT Jr.
Jean Mayer USDA Human Nutrition Research Center on Aging, School of Nutrition Science and Policy, Tufts University, Boston, Mass, USA.

OBJECTIVE: To determine if usual nutrient intake is related to a 5-year change in the amount of lens nuclear opacification assessed by computer-assisted image analysis. DESIGN: A sample of 408 Boston, Mass-area women from the Nurses' Health Study aged 52 to 74 years at baseline participated in a 5-year study related to nutrition and vision. Usual nutrient intake was calculated as the average intake from 5 food frequency questionnaires that were collected over a 13- to 15-year period before the baseline evaluation of lens nuclear density. Duration of vitamin supplement use before baseline was determined from 7 questionnaires collected during this same period. We assessed the degree of nuclear density (opacification) using computer-assisted image analysis of digital lens images with amount of nuclear density measured as a function of average pixel gray scale, ranging from 0 (clear) to 255 (black). RESULTS: Median (range) baseline and follow-up nuclear densities were 44 (19 to 102) and 63 (32 to 213). The median (range) 5-year change in nuclear density was 18 (-29 to 134) and was positively correlated with the amount of opacification at baseline (Spearman correlation coefficient = 0.35; P<.001). Geometric mean 5-year change in nuclear density was inversely associated with the intake of riboflavin (P trend = .03) and thiamin (P trend = .04) and duration of vitamin E supplement use (P trend = .006). CONCLUSION: Our results suggest that long-term use of vitamin E supplements and higher riboflavin and/or thiamin intake may reduce the progression of age-related lens opacification.

Dev Ophthalmol. 2005;38:120-47.
Nutrition and retina.
Schmidt-Erfurth U.
Universitatsklinik der Augenheilkunde und Optometrie, Vienna, Austria.

The impact of nutrition on manifestation and progression of retinal diseases has become an important, controversial topic within recent years. The awareness of this topic in the general population has increased partially due strong commercial advertisements of supplements and diets. However, many potentially beneficial nutritional effects on retinal diseases have not been proven in prospective clinical trials. It is only for a few relatively rare diseases, such as retinitis pigmentosa or gyrate atrophy, that adjustments in nutrition have been proven effective and widely accepted. However, for the majority of patients with retinal diseases the impact of nutritional factors is still insufficiently understood. Theoretically, supplementation of antioxidants could have a beneficial impact on a wide variety of retinal diseases or as a preventive measure by limiting the degree of oxidative damage. The only prospective, controlled, clinical trial providing proven benefit of antioxidant supplementation for a retinal disease is the Age-Related Eye Disease Study (AREDS). Patients with at least intermediate age-related macular degeneration (AMD) were shown to have a significant benefit with regard to disease progression by supplementing with high-dose antioxidants and zinc. It is however unclear whether other antioxidants, such as lutein or zeaxanthin, may be better and whether a preventive supplementation is useful. Especially studies on patients with diabetic retinopathy have implicated an impact of higher cholesterol levels on the progression of the disease. High-fat diets have been overall associated to a number of retinal diseases. With the current knowledge it seems prudent to advise everyone a balanced, low-fat diet as well as vitamin supplementation within the recommended daily allowance. Smoking is an essential factor for oxidative stress, and its cessation should be recommended to everybody in order to prevent or slow down progression of retinal disease. High-dose antioxidant supplementation according to the AREDS trial should currently only be recommended to non-smokers with at least intermediate AMD. Based on results from experimental studies, further prospective clinical studies are warranted on the prevention and inhibition of disease progression in the most common retinal diseases by nutritional means.

2002

Eye. 2002 Jul;16(4):463-5
Effect of religious fasting on intra-ocular pressure.
Dadeya S, Kamlesh, Shibal F, Khurana C, Khanna A.
Guru Nanak Eye Centre Maulana Azad Medical College New Delhi 110002, India.

AIM: The objective of this study was to find out the effect of religious fasting on intra-ocular pressure. METHODS: Intra-ocular pressure by applanation tonometer was measured four times a day in 38 healthy young adult male patients. The mean age of patients was 29 years. Body weight was measured to assess the extent of dehydration caused by fasting. RESULTS: There was a statistically significant difference between the intra-ocular pressure during fasting and the non-fasting period (P < 0.001). There was weight loss ranging from 0.4 to 1.5 kg. CONCLUSION: Fasting alters the diurnal intra-ocular pressure in the study population, ie young males 22-38 years.