02 May 2020Diet, Exercise and Glaucoma

Glaucoma is a complex condition and though well studied it’s not fully understood.  What has become clear over time is that glaucoma is more than just high eye pressure.  It is affected by our overall health, our diet and our cardiovascular function. Diabetes and high blood pressure both have negative effects on glaucoma – as does being sedentary and having a poor diet.

If you have glaucoma and are thinking about making some lifestyle changes, good for you.  There is plenty of research showing that you’re making the right choice.  In fact, people who have been sedentary have been shown to have the greatest gains when they incorporate exercise, increased activity and dietary changes into their lives1.

Exercise

With few exceptions, what is good for your heart is good for your eyes2.  Aerobic exercises such as walking, biking, swimming, and jogging have been shown in multiple studies to have benefits for your eyes.  People who perform 30 – 45 minutes of aerobic activity 3-4 days per week have been shown to have lowered eye pressure (IOP)3.   Aerobic activity also benefits cardiovascular health and a healthier heart and blood vessels means improved blood flow and oxygenation to your optic nerve and retina.

In a recent study on activity level and glaucoma, participants at baseline averaged 5,313 steps and 2.5 hours of non-sedentary activity a day with 11 minutes of vigorous activity.  By boosting their non-sedentary activity to 5 hours a day (walking an additional 5,000 steps) or doing 120 minutes of moderate to vigorous activity, the rate of vision loss decreased by 10%4.

A review of the results of several studies on activity level and glaucoma showed that sedentary people had better improvement in eye pressure than those who were already active.  So it’s really important for those patients with glaucoma who are sedentary to realize that they potentially have the biggest benefit from increasing their activity levels.

If you swim, try to find goggles that rest with pressure on the cheekbone and upper brow, not smaller goggles that rest just on the eyelids.  The goggle strap can put increased pressure on the soft tissues around the eye and orbit and potentially increase your eye pressure.

Weight lifting can be beneficial for glaucoma, but with some caveats.  Weight training has been shown on balance to be good for cardiovascular health and can lower IOP.  However it is important with weight training for patients with glaucoma to avoid exercises that put your head in an inverted position (eyes below the heart).

When your eye level is below your heart, you have increased blood pressure in the venous system (the blood vessels taking blood away from your tissues and back to the heart).  If the pressure in your veins is higher than normal, this can lead to increased pressure in the eyes because fluid can’t drain out as well through the eye’s filtration system.

So if you have glaucoma and are thinking about starting weight training or already lifting weights you should avoid exercises such as a decline bench press or headstands or handstands.  Likewise you should not use inversion tables.  Studies have shown that healthy adults who perform a handstand position (where your eyes are maximally placed below your heart) can double their eye pressure5.

Patients with moderate to advanced glaucoma should also avoid large compound maneuvers such as squats, bench press, dead-lifts, or leg presses with heavyweights.  At least one study has shown negative impact on IOP with heavyweights and compound exercises (bench press).6  It’s better to isolate one leg or arm at a time to lower cardiac stress and increases in venous pressure.

Competitive weight lifting or bodybuilding can have deleterious cardiovascular effects at higher BMI.  The effects of anabolic steroids and HGH are presumed to have negative effects as well on cardiovascular health and IOP by extension.  Performance enhancers can make it easier to get “back in shape” but in the long run are deleterious and should be avoided.  Patients with glaucoma should have close monitoring of eye health if they compete in weight lifting/bodybuilding and may want to consider the increased aerobic activity and reduced strength training.

Another important thing for patients with glaucoma to avoid weight lifting or any other sport is forceful breath-holding – also called the Valsalva maneuver.  In any activity, you should breathe normally through the exercise and not forcefully hold or expel your breath.  Valsalva, similar to headstands, increases your venous pressure and your eye pressure.

Yoga is generally not problematic for patients with glaucoma with the exception again of inverted yoga poses.  Downward dog position has been shown to raise IOP by as much as 10 mm hg7 and should be avoided.  Postures where the legs are above the head while the torso and head are on the floor usually raise IOP by about 4-5 mm hg.7  In studies of Yoga with inverted head positions, eye pressure elevation is generally short-lived – just a few minutes and returns to normal.  Patients with moderate to advanced glaucoma should avoid inverted yoga positions and should work with their yoga instructor to modify these positions.

So if you’ve already started an exercise regime of aerobic activity with some weight training, that’s excellent.  But it’s important to understand that any benefit exercise has for your glaucoma will be nullified by a bad diet.  A recent study on mice found that diets high in sugar and fat made the optic nerve more vulnerable to injury – and exercise did not offset the negative effect of this diet.8

Diet and Glaucoma

As Americans, we know we eat a lot of the wrong foods.  We consume far too much processed foods, sugars – especially high fructose corn syrup (in almost all processed foods, sports drinks, soft drinks, juices), saturated animal fats (bacon, sausage, cheese) and trans fats.  Excessive intake of these dietary elements eventually leads to the metabolic syndrome of hypertension, diabetes, and obesity.  Unfortunately, unhealthy food is everywhere - in fast food, restaurants and microwave dinners and even in a lot of our favorite dishes we like to make at home.

When trying to make healthy lifestyle changes, the two most important things to consider in a diet are balance and size.  The diet needs to be well balanced with healthy nutrients and the portion size needs to be controlled.

When changing your diet to lose weight or maintain a healthy weight it’s critical that you use a balanced, healthy approach.  The Mediterranean diet has proven to be one of the best in terms of longevity and health.  Combining healthy fats such as olive oil, avocado, nuts (almonds, walnuts) and fatty fishes such as wild-caught pacific cod, and salmon, anchovies and mackerel and low-fat red meat balanced with increased consumptions of vegetables, fruits, and legumes (beans) is best for your health overall and your eyes as well.

The National Health and Nutrition Examination Survey (NHANES) followed 83 million people over a four year period ending in 2008.  Over 3 million of the participants in the study had glaucoma.  For participants who employed a variety of diet methods, only calorie restriction (eating less) was associated with decreased risk of developing or progression of glaucoma.  Using dietary supplements, diet pills, dietitian consults (not independently studied) and drinking more water were all associated with increased risk of glaucoma or glaucoma progression.9

Unbalanced diets can have deleterious effects.  There was a report in the UK in 2019 of a teenage boy who ate a carbohydrate only diet (chips, bread, and other processed starches) and went blind from optic nerve disease due to B12/Vit D. deficiency.  People who eat a vegan-only diet and aren’t extremely careful can wind up with anemia (which can exacerbate glaucoma) and iron, zinc, and other micronutrient deficiencies.  People who consume excessive amounts of just one vegetable to increase the sense of fullness (cabbage only diets, carrot only diets) can also have deleterious eye and health consequences. More than one patient in our clinic has developed retinal crystalline deposits from excessive carrot intake.   

Patients often ask about dietary supplements.  It has been theorized (though not proven in controlled prospective randomized studies) that CoQ10, resveratrol (an antioxidant in red wine), and goji berries may have some potential benefit in treating patients with glaucoma.

To summarize:

  • Make sure your glaucoma is medically or surgically controlled and that you’re following up with your eye doctor
  • Eat a healthy, balanced diet with portion control
  • Exercise 3-4 times per week with aerobic activity and occasional weight training
  • Yoga is ok, but avoid any exercise with a head-down position
  • Breathe through your exercises – no forceful breath holding

1  Roddy G. et al. Clin J Sports Med. 2014;24(5):364-372.

2 Weiner G. Eyenet.  20 ;:9-12.

3 Schmidt KG et al. Graefes Arch Clin Exp Ophthalmol.  1996;235(8):527-532.

4 Lee MJ et al.  Ophthalmology.  Published online Oct. 10, 2018.

5 Weiner G. Eyenet. 20;:9-12.

6 Vieira GM et al. Arch Ophthalmology.  2006; 124(9):1251-1254.

7 Weiner G. Eyenet. 20;:9-12.

8 Chrysostomou V et al. Exp Eye Res. 2017; 162:104-109.

9 Hemphill, N. Ocular Surgery News. 2019; ;19.