Since caffeine is a diuretic (causes the body to lose water by expelling more fluid through the urine), it has been investigated as a potential cause of dry eyes. A couple of large, population-based cohort studies found no association between caffeine intake and dry eyes.[1][2] Moreover, an RCT in healthy individuals without dry eyes found that caffeine ingestion caused a significant intake in tear production, suggesting [3] that it may actually have the opposite effect.
References
- ^Jeong KJ, Choi JG, Park EJ, Kim HE, Yoo SM, Park SGRelationship between Dry Eye Syndrome and Frequency of Coffee Consumption in Korean Adults: Korea National Health and Nutrition Examination Survey V, 2010-2012.Korean J Fam Med.(2018-Sep)
- ^Magno MS, Utheim TP, Morthen MK, Snieder H, Jansonius NM, Hammond CJ, Vehof JThe Relationship Between Caffeine Intake and Dry Eye Disease.Cornea.(2022-Jan-26)
- ^Osei KA, Ovenseri-Ogbomo G, Kyei S, Ntodie MThe effect of caffeine on tear secretion.Optom Vis Sci.(2014-Feb)