Milk Chocolate vs. Dark Chocolate: Which Is Better?

We have known for more than a decade that chocolate is a good antioxidant and, therefore, healthy for the eyes.

A 2003 study by scientists at Cornell University in New York and Seoul National University in Korea showed that cocoa has almost twice the antioxidant power of wine, 2-3 times that of green tea, and 4-5 times that of black tea. Chang Yong Lee, who headed the study, suggested that a cup of hot chocolate in the morning, a cup of green tea in the afternoon, and a glass of red wine in the evening would satisfy our daily antioxidant requirement.

But which kind of chocolate is better? Milk or dark? A small 2018 study published in JAMA Ophthalmol helps to answer the question.

According to the authors, consumption of dark chocolate can improve blood flow, mood, and cognition in the short term, but until now, little has been known about the possible effects of dark chocolate on visual performance. To find out, they tested 30 young adults, all of whom were visually healthy. Within two hours of consuming milk chocolate and dark chocolate, their small-letter contrast sensitivity was significantly higher after consuming dark chocolate. Their large-letter contrast sensitivity was slightly higher after dark chocolate, and their visual acuity improved slightly.

The findings favored dark chocolate as better for the eyes, but the duration of that effect and how it influences real-world performance await further testing. And, of course, there is a point at which chocolate consumption may do more harm than good, considering its high caloric content (1 oz = approximately 155 calories).

SOURCE: Effects of Milk vs Dark Chocolate Consumption on Visual Acuity and Contrast Sensitivity Within 2 Hours–A Randomized Clinical Trial. Jeff C. Rabin, OD, MS, PhD, et al (JAMA Ophthalmol. 2018;136(6):678-681. doi:10.1001/jamaophthalmol.2018.0978)