The idea that carrots are a superfood for the eyes seems to be instilled into us at a young age, but unlike other 'old wives tales' this one doesn't seem to fall to the wayside as we get older.  It's likely because as we grow older, we slowly start to abandon all the 'old wives tales' that don't withstand the rigours of basic science, but in this case the science does seem, at least initially and very superficially, to back up the particular claim.  Any sort of investigation into carrots reveals that they contain beta-carotene, and any investigation into eyesight reveals that Vitamin A (and by extension beta-carotene) is absolutely required for human sight, particularly for vision in low light levels.  So most people take this as enough data to reconfirm their belief that carrots are the ultimate eye food.  But stopping there would be foolhardy, as what is getting glossed over is that being deficient in Vitamin A is fairly rare in a western diet, and in cases where it is deficient (in populations at risk such as alcoholics and the homeless), other foods or supplements containing actual vitamin A (as opposed to simply beta-carotene) are far more effective at being absorbed by the body and reaching the eyes.  This is because beta-carotene needs to be converted in our GI tract to vitamin A, and the ratio appears to be around 20:1, so lots of beta-carotene (found in carrots) is needed to produced far less Vitamin A.

So not only are we rarely deficient in Vitamin A, but carrots don't even sound like the best way to get it, leaving us with the question: Why do people believe carrots are the best food to help with eyesight?  To answer that, we need to go back 77 years and across the Atlantic.

Life in 1940s Britain was tough, as WW2 was raging on, and the Battle of Britain being fiercely fought between the Royal Airforce (RAF) and the German 'Luftwaffe' in the skies above.  Not only were there food shortages due to the naval blockades and German u-boats prowling the shipping lanes attacking merchant ships, but the urban areas of Britain were being relentlessly bombed by the German air force during nightly blitzkrieg attacks.  

Due to food shortages and subsequent food rationing, Britain's Ministry of Information made a concerted effort to educate all citizens to start planting and consuming foods that can be easily grown in their home gardens.  Carrots, in particular, were a focus of numerous public education campaigns, as they were relatively easy to grow in the British climate.  To further entice people to not only grow carrots but to also eat them, the Ministry of Information used various degrees of propaganda espousing the benefits of carrots, creating 'tasty' recipes (such as 'carrots on a stick' for kids), and even going so far as the creation of a cartoon doctor called "Dr. Carrot".  

 The always delicious "carrot-on-a-stick"

The always delicious "carrot-on-a-stick"

The main health benefit of carrots being advertised was the improvement of night vision, as it was known at that time the carrots contained beta-carotene, and that was understood to be important for eyesight.  This combination of patriotism plus health benefits was enough motivation to get people to buy-in to the "carrot-as-a-food-staple" narrative, and subsequently, British consumption of carrots increased significantly.  This increased demand, however, couldn't keep pace with the drastic increase in supply and with all the new "home gardeners", the Ministry of Food was reporting massive surpluses of carrots.  It wasn't until RAF pilot John "Cat Eyes" Cunningham shot down the first German airplane in the dead of night, did the notion of "carrots as a super eye food" really explode, and with it, the public's consumption of them.  

 Photo courtesy US National Archives

Photo courtesy US National Archives

Up until that point, the German Luftwaffe had essentially bombed Britain at will, almost unimpeded, with Britain resorting to country-wide blackouts to help hide major cities from the relentless enemy squadrons prowling the skies above.  This pitch blackness did accomplish its goal of making the cities harder to target, but it also made shooting down enemy aircraft all the more difficult.  The constant buzzing of unseen aircraft above and the imminent threat of a bomb exploding nearby left citizens hiding in bomb shelters, in a constant state of fear.  It therefore was a pretty big moral boost when "Cat Eyes" Cunningham knocked one out of the air, so to speak.  And he didn't just stop at one, eventually racking up 20 total "kills" of German aircraft, with the rest of the RAF pilots also starting to tally impressive numbers themselves.  It wasn't long after that the Battle of Britain begin to turn in the home team's favour.  

Unknown to the public through all this, and possibly the Germans too, was how had the RAF pilots all of sudden become so accurate in the dark?  Turns out, the RAF had recently invented air-based on-board RADAR, which was a huge improvement over the traditional ground-based RADAR, and allowed the RAF to pinpoint incoming German aircraft long before they entered British airspace, and sometimes even before they left the skies over mainland Europe.  This technological evolution was a massive advantage to the British, and something they obviously wanted to keep secret from the Germans for as long as possible.  

Enter the carrot.  

In what appears to be a pretty perfect "two birds with one stone" scenario, the British government promoted the idea that the real reason "Cat Eyes" Cunningham and the RAF were getting so darn good at shooting in the dark was that they had vastly superior night vision from all the carrots they were eating.  Since there was a surplus of carrots, and the government wanted people eating more carrots anyway, this was the perfect way to not only help keep the RADAR secret from the Germans but to also deal with the carrot surplus at the same time.

Almost 80 years later, and the myth is still widely accepted as common knowledge, and it shows no signs of letting up. It makes one wonder what would have happened if the British happened to promote the use of a vegetable that is actually an eyesight superfood, such as kale, or spinach (both of which are chocked full of lutein, which helps protect against macular degeneration).  From a public health perspective, there would possibly be a reduced rate of macular degeneration today, as everybody would at least be more aware of the benefits of lutein and how their diets are typically deficient in it.  On the bright side, at least they didn't choose something that was harmful to the eyes, like drinking moonshine.  That could've really changed the war, especially if the Germans tried to emulate the British in an attempt to improve their night vision as well.

 

Dr. Burke is an optometrist practicing at Calgary Vision Centre.  He is no relation to Dr. Carrot.  Opinions above do not constitute medical advice, and readers should consult with their optometrist if they have questions or concerns about their eye health