Caffeine and Dry Eye

Medically Reviewed by Whitney Seltman, OD on August 17, 2022
3 min read

If you’re frustrated with dry eye, it makes sense to think about changing some of your habits to stop your symptoms. While less screen time and less alcohol might help, here’s one thing you don’t need to give up: your morning coffee.

Some people with dry eye swear off coffee and tea, assuming they make the problem worse. But some research suggests the opposite. Caffeine may help those symptoms.

When you have dry eye, your body doesn’t make enough tears, or the tears may not have the right consistency to keep your eyes moist. That means you don’t have enough to protect the surface of your eyes and wash away dust and gunk. So your eyes can start to feel scratchy and irritated.

This is where caffeine may help. Two small studies have found that it seems to increase the amount of tears in your eyes.

In one study from Japan, researchers divided 78 people into two groups. One got capsules with 200 mg to 600 mg of caffeine, depending on the person’s weight. That's roughly the amount in 2 to 6 cups of coffee. The other got placebo capsule with just a filler inside. The researchers found that the people who got caffeine had more tears.

A smaller study from Ghana had similar results, showing a boost in tear production from caffeine. These studies fit with earlier research that showed people who used caffeine had lower rates of dry eye than people who didn’t.

 

Does the cure for your gritty, itchy eyes lie at the bottom of a mug? Not necessarily, experts say.

While research is promising, the studies have been small. For now, eye doctors don’t know enough about the effects of caffeine to recommend it as a formal treatment. Keep in mind that caffeine can affect your health in other ways, such as causing more anxiety, higher blood pressure, and trouble sleeping.

So if you don’t already sip caffeinated drinks, having dry eyes is not a good reason to start.

On the other hand, if you already start off the day with coffee or tea, there’s no reason to stop. You can try to adjust the amount you drink to see if it makes a difference in your symptoms. Experts say that up to 400 mg of caffeine a day, the amount in about 4 cups of coffee, seems to be safe for most people. But your best guide is how caffeine makes you feel.

And what about the idea that caffeine could dehydrate you because it makes you pee more? Would that make it bad for dry eye? While it’s a common theory on the web, the evidence doesn’t back it up. But if you want, you can drink water along with your coffee or tea to make sure.

If you’re struggling with dry eye, see an eye doctor. It’s a common condition, especially as you get older, and it can have many different causes. Some people may need changes in their medicines, prescription treatment, or other procedures to get relief.