If you’ve ever experienced blurred eyesight after having one too many to drink, you won’t be surprised to learn that alcohol can have an effect on the way that our eyes focus.

Here’s what happens to our eyes when we drink:

• Dilated pupils. Because alcohol relaxes muscles all over the body, it causes the pupils to dilate as the muscles in the iris expand.
• Poor focus. Too much alcohol can affect the way that the muscles in the eye work together and react to signals from the brain – leading to blurry vision and an inability to focus.
• Slower reactions to light. Normally, when we enter a darkened environment, our eyes dilate to take in more light. Conversely, when we are surrounded by bright light, our pupils contract so as not to damage the retina. However, just as alcohol can affect the speed of our movement and reactions to other stimuli, it can affect the way our eyes react to light – meaning that our eyes can be slow to adapt to sudden bright lights or being plunged into darkness, after we’ve consumed alcohol. This is an effect that will wear off as the body processes the alcohol – so the more you drink, the longer it will last.
• Have you ever noticed how some people’s eyes turn red or bloodshot when they drink alcohol? That’s down to the blood vessels in the eye expanding as a reaction to the alcohol consumed.
• Dry eyes. Dry eyes are more likely to occur after drinking alcohol, because it’s a diuretic that makes you dehydrate easily.