Dark chocolate has been long recognised for its health-boosting properties, including decreasing cholesterol and blood pressure, but it has now been revealed that it may be beneficial for our eyesight. Recent studies at The University of Reading have shown that dark chocolate contains flavonols which may help to improve eyesight in dark or low-contrast conditions. The study involved 30 participants aged 18-25 who ate 35g of dark chocolate or the equivalent of white chocolate at one week intervals. Those who consumed dark chocolate were able to see 17% better than when they ate white chocolate. They were tested 2 hours after they ate a piece of dark chocolate but lead researcher David Field suggests the effects could kick in after just one hour.The tests to determine visual sensitivity were carried out by asking the participants to read numbers that became progressively similar to the background. To test motion sensitivity, participants were asked to detect moving signal dots against a moving background.
Dark chocolate is a good source of flavonols because it has a high cocoa content, unlike white chocolate which is largely cocoa butter. Flavonols are believed to be beneficial for eyesight because they increase blood flow to the retina in the eyes. The retina is responsible for receiving an image and sending it to the brain. This task requires a lot of energy, yet eyes do not naturally have a plentiful blood supply. Better blood flow means the eyes can function at their best, which may be a possible reason for improved visibility in difficult conditions.
In addition, dark chocolate contains lutein and zeaxanthin which are proven to protect eyesight by reducing the risk of developing common conditions such as cataracts and macular degeneration.
But before we all run to the shops to stock up on chocolate, it’s important to know that even the researchers are unsure how much we should eat to reap the benefits. For the experiment, David Field and his team used a chocolate bar with a high percentage of cocoa flavonols (773 milligrams to be exact), but most chocolate manufacturers fail to list flavonol content on their packaging. As with most foods, consuming chocolate to excess will inevitably result in weight gain, so it is important to eat small amounts as part of a balanced diet.Victoria writes health and food articles for Direct Sight, one of the leading online suppliers of varifocal lenses