Everyone in my immediate family has 20/20 vision.  My mom always claims that we all have perfect vision because of her selectiveness of what she would feed us (a hefty amount of carrots). Seriously, carrots are incorporated in basically every meal, in some way or another.  If carrots are not an ingredient in the main course they are most definitely going to be somewhere else in the dinner. At a family dinner in my household, one could expect either peas and carrots as a side dish, carrot cake for desert, or apple and carrot juice (which is surprisingly tasteful).  If carrots truly do help one’s eyesight like the myth claims, I’d have the best eyesight in the world. How true can this correlation between carrots and better eyesight actually be?  Do carrots actually benefit the human eye?

After analyzing the various studies, articles, and opinions on the matter, I found that there is no definite answer, shockingly.  I did find, more often than not, that scientists believe carrots do benefit eyesight.  Based on the lack of evidence provided by those who disagree that carrots have a benefit on eyesight, I lean towards believing in the so-called “myth.”  The null hypothesis of this study is that carrots have no effect on one’s eyesight.  The alternative hypothesis is that carrots do in fact have a positive effect on one’s eyesight.

The Cleveland Clinic study refers to two experiments.  The first experiment, that took place in 2005, had Nepali women, suffering from “night blindness,” divided into six groups and then given certain foods depending on what group they were placed in.  The University of Maryland Medical Center defines night blindness as “poor vision at night or in dim light.”  One of the six groups, that the Nepali women were divided into, ate a large sum of carrots each week, over a six-week period.  The other five groups were given different foods, all rich in Vitamin A, over the six-week period. In this experiment, the null hypothesis is that the carrots will not lessen the night blindness in the Nepali women.  The alternative hypothesis is that the carrots will lessen the night blindness in the Nepali women.  The study’s conclusion is consistent with the alternative hypothesis.  The carrots helped increase the Nepali women’s responsiveness to darkness.

The second experiment, found in the Cleveland Clinic study, used around 2,300 participants, all older than 55.  This was an observational experiment that looked at how these participants got their dose of carotenoids.  Oregon State University defines carotenoids as “warm colored pigments that are synthesized in plants.” The observational experiment found that carrots were responsible for most of the beta-carotene (a type of carotenoid) consumption. Beta-carotene has many positive and negative effects, but in regards to eyesight, beta-carotene is used reduce the chance of night blindness during pregnancy.  Essentially the experiments in the Cleveland Clinic Study show that carrots have a positive effect on eyesight, thus consisting with the original alternative hypothesis.

This article, released by Harvard Health Publications, says that carrots don’t necessarily have that large of a benefit to individuals who have healthy eyes.  Carrots do in fact have an effect on people who do not have healthy eyes.  Most people, as they get older, start to experience a decline in the well-being of their eye.  Harvard Medical School says that for these individuals eating carrots does make a difference.  The results of the second study, reviewed by the Cleveland Clinic, agree with this.

This report, written by the Guelph Food Research Centre, explains that carotenoids (previously mentioned), that are found in carrots, have large effects on the human eye. The report describes how carotenoids make up the main pigments found in the human retina, but this doesn’t show carrots benefitting eyesight.  These same carotenoids do reduce the risk of an individual getting “age-related macular degeneration.”  The National Eye Institute defines age-related macular degeneration as “a disease that blurs the central vision individuals need for straight ahead activities.”  Although the mechanics of how carotenoids reduce the risk of this disease is not clearly explained, it is reasonable to conclude that carrots would have more of a beneficial effect than a negative one.  Also, lutein and zeaxanthin, both types of carotenoids, are found in carrots.  These two carotenoids are known to be beneficial for the human eye (and body) because of the results of many “epidemiological, clinical, and interventional” studies.  The goal of this report, which was made clear by the author, was to show the favorable effects brought about by these two carotenoids that are found in carrots.

Even if the conclusions of all of these studies were proven to be incorrect or caused by a third confounding variable, carrots have also not been proven to have any negative effects on the human eye. Therefore, at worst, carrots have a benign effect on the eye.  Personally, because there is no definitive answer, I believe that the alternative hypothesis is correct.  I guess the only reason someone should not eat carrots is if they don’t like the taste.