How To Prevent Glaucoma Through Your Lifestyle And Diet
Although the primary focus of glaucoma management in intraocular pressure (IOP) lowering, many patients want to know what else can be done to reduce their glaucoma risk or help control their disease. There are a few diet and lifestyle measures that can help with glaucoma; however these are to be used alongside regular glaucoma treatment, not instead of it.
How Your Diet Affects Glaucoma
As always, moderation is the best approach and this should be applied to the dietary suggestions outlined below.
1. Fruit and Vegetables:
Antioxidants and nitrates found in fruits and vegetables may reduce glaucoma risk. It is good to eat plenty of fruit and vegetables, especially those rich in Vitamin A and C, carotenes and nitrates. These include carrots, green leafy vegetables, cruciate vegetables, citrus fruits, berries and peaches. [1,2]
2. Vitamin B3
Vitamin B3 might be beneficial in preventing glaucoma, according to some lab-based evidence, and low levels of B3 might be harmful. [3,4] This does not mean oral supplements need to be taken – a healthy, balanced diet is sufficient for most people to get sufficient B3. Foods rich in B3 include turkey, chicken, mushrooms, peanuts, tuna, liver and Vegemite.
3. Omega-3 acids
Omega -3 fatty acids, found in oily fish (eg. salmon) and chia, can reduce the chance of glaucoma worsening, according to one study. 
Caffeine in coffee or other caffeinated drinks can raise your eye pressure for about two hours.  Caffeine increases the production of fluid (aqueous) within the eye. This does not cause any problems for most people, but people with glaucoma, especially advanced glaucoma should consider reducing caffeine intake if it exceeds 3-5 cups of coffee per day.  De-caffeinated drinks are probably a safer option for those at-risk people.
As caffeine levels in tea are low there is no additional risk from drinking tea. In fact, tea drinkers (one cup per day) may have lower rates of glaucoma than non-tea drinkers.  Tea contains flavonoids that may improving blood flow to the optic nerve and reduce glaucoma risk. 
6. Dark Chocolate
Dark chocolate also contains flavonoids and has been proven to be beneficial in patients with cardiovascular and vascular diseases. Further research is needed to know of there is any benefit for glaucoma patients. 
Red wine consumed in moderation may reduce the risk of glaucoma, but further studies are needed to confirm this.  Grapes contain antioxidants that may improve blood flow to the optic nerve and thereby make it more resistant to raised eye pressure. 
It is very important to stay well hydrated; water is the essence of life. However too much volume of water in a short interval may transiently increase eye pressure especially if drainage of fluid (aqueous) from the eye is impaired. For people with glaucoma, especially advanced glaucoma, more frequent and smaller volumes of water, spread over a greater time period, is recommended.
Obesity is linked with raised eye pressure.  Maintaining a healthy weight is beneficial to prevent many diseases, not just glaucoma.
10. Oral Supplements
There are no proven benefits for using dietary tablet-based supplements in glaucoma patients. 
How Your Lifestyle Affects Glaucoma
Most activities are not harmful for glaucoma; people with glaucoma should generally continue to do the things they love. However, the following activities should be limited for those with more advanced glaucoma:
Yoga positions can be associated with increased IOP, especially those with the head below or at level with the heart,  Yoga practitioners with glaucoma can continue their yoga but these positions are best avoided:
2. Wind instruments
Some wind instruments, eg trumpet, trombone, bagpipes, when played can increase pressure around the face and upper airways – this raises IOP and can worsen glaucoma. People with glaucoma should play these with caution among people with glaucoma (especially advanced glaucoma).
Other less forceful wind instruments eg clarinet, flute are quite safe.
Swimming goggles can increase IOP while they are worn.(16) Smaller goggles that sink inside the eye socket are most concerning. Larger snorkelling-type goggles have less impact on eye pressure and are safer; these should be worn in preference to smaller ones. However, repeated goggles use has not been shown to be a risk for glaucoma.
4. Neck ties
Closed collars (with ties for example), if worn too tight can increase pressure in the veins of your head and neck and thus increase eye pressure too. People with glaucoma (especially more advanced glaucoma) should avoid tight neck ties.
5. Air travel
Flying is very safe for people with glaucoma – it causes only a mild temporary elevation in IOP that is generally safe.
Regular moderate to vigorous-intensity exercise like brisk walking or jogging can reduce IOP; this is beneficial for people with glaucoma(17-21)
However before commencing an exercise program for eye health, consult with your ophthalmologist. People with less common eye conditions namely pigment dispersion syndrome (PDS) or pigmentary glaucoma (PG) may develop raised IOP when jogging or performing higher-intensity exercise.(22)
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