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An Ounce of Prevention | Glaucoma control

Published:Monday | July 10, 2017 | 12:00 AM
Regular exercise can reduce eye pressure.

Glaucoma is a rather mysterious eye disease and a leading cause of blindness worldwide. The pressure inside the eye is called intra ocular pressure (IOP). In glaucoma, a raised IOP has been blamed for damaging the optic nerve and causing the loss of vision that occurs with this disorder.

However, while a high IOP is indeed often associated with glaucoma, this disease can also occur when the IOP is normal (normal-tension glaucoma). On the other hand, some people with elevated IOP may never develop glaucoma.

Glaucoma researchers report that long before there is an elevation in the IOP, nerve cells in the brain and eye responsible for vision are being damaged. UK based experts have discovered a build-up of an abnormal protein in the eyes and the brain of glaucoma as well as Alzheimer's disease sufferers. Our current understanding and treatment of glaucoma is quite incomplete as clearly, glaucoma is not just about a high eye pressure!

Glaucoma is a slow progressing disease. Early diagnosis is important as with treatment, vision loss may be controlled. It is a serious condition, requiring diagnosis, treatment and monitoring by a qualified ophthalmologist. Screening for glaucoma should involve not just checking for high IOP, but also an evaluation of individual risk factors.





Besides old age, other known risk factors include family history, ethnicity, diabetes and high blood pressure. The US National Eye Institute estimates that glaucoma is four to five times more common among blacks compared to white Americans, and that diabetics are almost twice as likely to have glaucoma as non-diabetics. Individuals with severe farsightedness or nearsightedness have an increased risk of developing glaucoma. The problem is very common in Jamaica.

The Physicians' Desk Reference, a manual on prescription drugs, lists close to 100 medications that can cause glaucoma, including blood pressure drugs, antidepressants and antihistamines used for allergies and steroids, such as Prednisone.

Current glaucoma treatment focuses on medication (eye drops and tablets) and surgery to reduce IOP. However, it is vital to also provide ongoing protection to the delicate cells of the optic nerve to prevent progression of vision loss.

Additional benefits may be derived from strategies that improve blood flow to the eye and maintain the integrity of the optic nerve. The following lifestyle practices should be a part of an anti-glaucoma programme.




Regular exercise can by itself reduce eye pressure, while impacting positively on other glaucoma risk factors such as diabetes and high blood pressure. In one study, a group of people with glaucoma rode stationary bikes for 40 minutes, four times per week for three months and reduced their IOPs by an average of 20 per cent. This benefit was maintained by continuing to exercise at least three times per week, but was lost if exercise was discontinued for longer than two weeks.




A diet rich in antioxidants and carotenoids is generally beneficial for eye health. The glaucoma sufferer's diet should emphasise fresh fruits, especially citrus and berries, and leafy green and yellow vegetables rich in the antioxidants vitamins A, C and E. Cherries, guavas, grapes and blueberries that contain bioflavonoids should be emphasised as these compounds help to prevent free radical damage and promote healthy blood flow to the eye.

Foods rich in magnesium and chromium like apples, brewer's yeast and kelp are also beneficial. Eat whole grains, nuts and seeds regularly. Studies indicate that regular green tea consumption helps protect the eyes from glaucoma damage, because the antioxidants in green tea are particularly concentrated in the eye.




An eye drop containing the antioxidant N-acetyl-L-carnosine (NAC) marketed under the trade name Brite Eyes is useful for eye health. NAC not only protects the eye against free radical damage and cataracts, but it also lowers IOP. One drop to the eyes twice daily is beneficial for glaucoma and cataract sufferers, as well as for general eye health.




Vitamin C in high doses, two to six grams daily, may assist in lowering IOP and maintaining the health of the blood vessels in the eye. It should be taken in divided doses throughout the day to maintain optimal levels of the vitamin in the blood.

Vitamin B12 has a specific ability to protect the delicate cells of the optic nerve. Vitamin B12 supplementation at higher-than-usual dosages helps protect against neurological damage to the eye from glaucoma.

Fish oil: The omega 3 fatty acid found in fish oil called docosahexaenoic acid (DHA) helps to protect an important structure in the eye known as the retina. DHA is concentrated in the retina and is useful in optimising vision. Three or more grams of DHA daily may be necessary for glaucoma.

Alpha-lipoic acid is another antioxidant that has attracted attention in the treatment of glaucoma as it appears to improve intra ocular pressure and visual function. Glaucoma research suggests a daily dose of 150 to 300 mg.

Pycnogenol is a supplement that, along with vitamin C, supports the health of blood vessels and prevents free radical damage. Two hundred to 300mg daily are recommended for glaucoma. Bilberry is often referred to as the 'eye herb' and it works in a similar way to pycnogenol.




Relaxation exercises and biofeedback sessions have shown promise in lowering IOP in some glaucoma patients. The reduced blood pressure, heart rate and muscle tension achieved with relaxation and biofeedback may be responsible for the improvements. Regular yoga practice may also be helpful.

It is important to minimise stress and cultivate a relaxed and restful lifestyle as glaucoma is aggravated by stress. Avoid excessive television viewing and prolonged computer use without regular breaks as such habits can lead to eye strain.

- You may email Dr, Vendryes at or listen to An Ounce of Prevention on POWER106FM on Fridays at 9:00pm. Visit