Your Amazing Eyes! 14 Fab Facts

Published on 10th March 2015 by Dr Stephen Doyle

From the number of times you blink a day, to the amount of brainpower your eyes use, we have 14 amazing facts about your eyes!

Did you know…..

• Your eye colour is determined by how much melanin is in your iris. People with brown eyes have more melanin whereas those with blue eyes have less allowing the collagen (which is blue) to show through.
• The first person to ever have blue eyes lived sometime between 6,000 and 10,000 years ago. Before then everyone had brown eyes. So if you have blue eyes you actually share a common ancestor with every other blue-eyed person in the world!
• Your eyes are extremely complex organs containing approx. 100 million cells called ‘rods’, which allow you to see in the dark, and 7 million ‘cones’, that allow you to see colour and detail.
• The only cells that survive from the time you are born until death are in your eyes.
• Eyes use more brainpower than any other part of your body - about 65%!
• The phrase ‘in the blink ofeye’ was coined because it is the fastest muscle in your body.
• On average we blink 17 times a minute, equating to 16,320 times in a 16 hour day and over 5.9 million times a year!
• The older we get theless tears we produce.
• Tears are made up of more than just water. They are a combination of fat, mucous and water which means that they don’t evaporate.
• The pupil of your eye can expand by as much as 45% when looking at something pleasing.
• Images that are sent to your brain are actually backwards and upside down.
• Retina scans for security purposes are becoming more popular because the iris has 256 unique characteristics compared to fingerprints which have just 40.
• Pirates used eye patches so they could quickly adjust between above and below deck. One eye became trained for the bright light, and the other for dim light.
• It’s impossible to sneeze with your eyes open.

All eye surgical procedures carry a level of risk including not obtaining the desired outcome, through to varying levels of visual loss. Your eye surgeon will discuss the risks and benefits, including ones specific to your circumstances, at the time of your pre-operative consultation.