Caffeine is a naturally occurring central nervous system stimulant belonging to the methylxanthine class and is widely recognised as the most utilised psychoactive stimulant worldwide.
Moderate coffee consumption does not directly cause vision impairment or eye damage. However, excessive coffee consumption or caffeine in any form for a long time can take a serious toll on your eye health.
The symptoms and signs range from twitching of eyes, stinging sensation, temporary blurring of vision, light sensitivity to more serious loss of vision due to macular degeneration.
According to the Food and Drug Administration (FDA) Trusted Source, a single 8-ounce cup of coffee contains around 80–100 milligrams (mg) of caffeine.
Caffeine intake is associated with an increase in intraocular eye pressure (IOP). Elevated IOP is a major risk factor for glaucoma. Therefore, excessive caffeine intake may increase the likelihood of developing glaucoma for some patients.
a. Damaged retina
b. Bleeding in the eye
c. Blurred vision
d. Vision loss
e. Fluid buildup under the retina (choroidopathy)
f. Nerve damage in the eye
Excessive caffeine intake is also associated with a temporary hike in blood sugar level. High blood sugar causes the lens of the eye to swell, which changes your ability to see.
Caffeine affects each person differently, if you have diabetes or if you find it hard to control your blood sugar, limiting the amount of caffeine in your diet might be helpful.
As with everything, it’s a good idea to enjoy coffee in moderation and try to keep on the lower side of the recommended daily caffeine allowance of 400mg.
Dr Ananya Ganguly, Ophthalmologist, Disha Eye Hospitals