Limits of Milk and Dark Chocolate Bars’ Effects on Human Visual Acuity and Contrast Sensitivity

To the Editor With great interest, we read the article published in the April issue of JAMA Ophthalmology entitled “Effects of Milk vs Dark Chocolate Consumption on Visual Acuity and Contrast Sensitivity Within 2 Hours: a Randomized Clinical Trial,” by Rabin et al.¹ This article concluded that “contrast sensitivity and visual acuity were significantly higher 2 hours after consumption of a dark chocolate bar compared with a milk chocolate bar, but the duration of these effects and their influence in real-world performance await further testing.”^1(p678) We have several comments on this study.