A study conducted at San Antonio's University of the Incarnate Word found that dark chocolate, right after eating it, could make your vision better.
"Very few studies have looked at the positive effects of dark chocolate on vision," said Dr. Jeff Rabin, a professor at UIW’s Rosenberg School of Optometry.
The study took place over a period of 52 days where nine men and 21 women each ate dark chocolate and milk chocolate candy bars days apart to see how each would affect their vision.
"This is the dark chocolate bar we used. It is high in flavonoids, which is what we tested. Also, this bar compared to other bars tasted pretty good,” student intern Nirmani Karunathilake said.
"On a separate day, we ran the same test but beforehand they ate this milk chocolate bar instead, which has much less flavanol content,” student intern Korey Patrizi added.
A flavanol is an active water-soluble plant compound appearing in many fruits, vegetables, and herbs. Over the long term, they can slow loss of function for people with diseases like Alzheimer's and Parkinson's and lower blood pressure.
"The second thing flavanols do is increase blood flow,” Dr. Rabin explained.
They tested visual acuity using a super vision chart, which showed slight improvement, and tested contrast sensitivity using two different sized charts where letters blend into the background.
"When we combined all three tests and found a composite score, we found an even greater improvement following dark chocolate in this composite score, a 60 percent improvement," Dr. Rabin noted.
But (sadly) this doesn't mean you should eat chocolate bars the size of a brick or drink chocolate syrup out of the bottle.
"Despite the effects of dark chocolate and flavanols, they also have sugar,” Dr. Rabin said. “So one has to take this with a grain of salt."