EFFECT OF MILK CHOCOLATE AND DARK CHOCOLATE ON INTRAOCULAR PRESSURE: A PROSPECTIVE COMPARATIVE STUDY

Background:  Intraocular pressure (IOP) is a critical physiological parameter that maintains ocular integrity and visual function. Dietary factors have been shown to influence vascular and ocular physiology. Dark chocolate contains high concentrations of flavonoids, methylxanthines, and antioxidants that may affect ocular blood flow and aqueous humor dynamics, thereby influencing IOP.  Objective : To evaluate and compare the short-term effects of milk chocolate and dark chocolate consumption on intraocular pressure among healthy young adults.  

Methods: A prospective comparative study was conducted among 70 healthy participants aged 18-25 years at Ahalia College of Optometry and Research Centre, Palakkad, India. Participants were allocated into two groups: milk chocolate (n=28) and dark chocolate (n=29). Baseline intraocular pressure was measured using a Perkins applanation tonometer. Each participant consumed 20 g of the assigned chocolate, and IOP was reassessed one hour later. Statistical analysis was performed using SPSS version 31. Non-parametric tests including the Wilcoxon signed-rank test and Mann-Whitney U test were applied. Statistical significance was established at p<0.05.  

Results: The mean age of participants was 19.79 ± 2.69 years. The milk chocolate group demonstrated a non-significant reduction in mean IOP from 11.91 ± 1.94 mmHg to 11.45 ± 1.80 mmHg (p>0.05). Conversely, the dark chocolate group exhibited a significant increase in IOP from 12.16 ± 2.07 mmHg to 12.97 ± 2.04 mmHg (p<0.001). Intergroup comparison demonstrated a statistically significant difference in post-consumption IOP values.

Conclusion: Dark chocolate consumption was associated with a significant short-term increase in intraocular pressure, whereas milk chocolate consumption did not significantly affect IOP. These findings suggest that cocoa-rich dark chocolate may transiently alter ocular physiology and should be considered when interpreting IOP measurements in clinical settings.