Antioxidants Help Glaucoma Patients

Glaucoma’s progress can be slowed as the result of taking the antioxidants vitamin E and N-acetyl cysteine.

A study published in Investigative Ophthalmology and Visual Science describes how reducing or reversing oxidation within the eyes may lead to the healing of the trabecular meshwork or outflow pathway in glaucoma patients.  As the name suggests, antioxidants (like vitamin C and N-acetyl cysteine, which is found in eggs) combat the natural process of oxidization.

According to the study, the free radicals that result from the oxidation process lead to the destruction of the trabecular meshwork, which can lead to increased ocular pressure and glaucoma.  (Issue: 49:1447-58, 2008)

Neuroprotective Agents

Medscape Today’s 2010 article addresses  slowing or halting the development of glaucoma by shielding undamaged nerve cells and restoring or rescuing nerve cells that have already been damaged.  In addition to describing more traditional pharmaceutical options for fighting glaucoma, the review includes a discussion of several antioxidants including melatonin, Coenzyme Q10, vitamin E, and ginkgo biloba.  Antioxidants, a more natural approach than the pharmaceuticals in the study, may be helpful neuroprotective agents.

Neuroprotective: Melatonin

According to an article published in The Journal of Pineal Research, evidence from a number of sources supports the assertion that increased free radical generation and altered nitric oxide (NO) metabolism contribute to glaucoma and uveitis. Data indicates that melatonin is an efficient antioxidant that has the ability to fight free radicals and break down nitric oxide and plays ” a promising role in the treatment of these ocular dysfunctions.”  Melatonin has few side effects even at high doses and can potentially do a great deal to protect ocular tissue.


Glaucoma in Black Women & Antioxidants

At the American Glaucoma Society meeting, Dr. JoAnn A. Giaconi reported that women who reported eating greater amounts of fruits and vegetables appeared to have a lower likelihood of developing glaucoma.

The foods that seemed especially protective included fresh oranges, peaches, spinach, collard greens, and kale.

Dr. Giaconi presented results from a review of data from the Study of Osteoporotic Fractures.  In this study involving a subset of 584 black women, glaucoma was diagnosed in at least one eye in 77 participants.  Disc photos and supra-threshold visual fields were evaluated in conjunction with Block Food Frequency Questionnaires on the participants’ daily food consumption.

The results?

  • Eating three or more servings of fruit or fruit juices daily decreased the odds of black women developing glaucoma by 79%
  • Eating one serving of collard greens or kale decreased the odds of glaucoma by 57%
  • Eating more than two servings per week of fresh oranges and peaches also significantly decreased the chance of developing glaucoma.

Researchers believe that the antioxidants in fruits and vegetables (vitamin A, alpha- and beta-carotene, folate, lutein, zeaxanthin) can potentially block oxidation stress that can lead to cell damage in glaucoma.

SOURCE:  Giaconi JA, et al. Nutritional associations with glaucoma among older black women. Paper presented at: The 18th Annual AGS Meeting; March 8, 2008; Washington, DC.

Fruits and Vegetables

Researchers at the Department of Ophthalmology and Jules Stein Eye Institute, University of California-Los Angeles, recently studied the association between consumption of fruits and vegetables and the presence of glaucoma.

1,155 women located in multiple centers in the United States participated in this cross-sectional cohort study. Glaucoma specialists evaluated the women for glaucoma; consumption of fruits and vegetables was assessed using a food frequency questionnaire.

Among the 1,155 women studied, 95 (8.2%) were diagnosed with glaucoma. Analysis of the relationship between selected fruit and vegetable consumption and glaucoma showed:

  • Glaucoma risk was decreased 69 percent in women who consumed at least one serving per month of green collards and kale compared with those who consumed fewer than one serving per month.
  •  Glaucoma risk was decreased 64 percent in women who consumed more than two servings per week of carrots compared with those who consumed fewer than one serving per week.
  • Glaucoma risk was decreased 47 percent in women who consumed at least one serving per week of canned or dried peaches compared with those who consumed fewer than one serving per month.

Although researchers note that more studies are needed to investigate the relationship between nutrition and glaucoma, research to date does indicate that a higher intake of certain fruits and vegetables may be associated with a decreased risk of glaucoma.

SOURCE: “Glaucoma risk and the consumption of fruits and vegetables among older women in the study of osteoporotic fractures”, Coleman, et al, Am J Ophthalmol. 2008 Jun;145(6):1081-9.