Eat Your Carrots - The Effects of Vitamin A on Eye Health

Sarah Ma

Have you ever heard someone tell you to “eat your carrots” because it will help you “see better”? The saying stems back to the Second World War when Britain promoted carrots as a superfood to enhance night vision. Whether or not carrots have a significant impact on our vision is still being researched however, there is some truth that carrots are good for eye health due to the large presence of a substance called beta-carotene.

Beta-carotene is a naturally occurring pigment found in fruits and vegetables which is responsible for providing it’s bright orange color to the vegetable. It is considered a provitamin A carotenoid and is considered the most important precursor to vitamin A, but also concurrently acts as an antioxidant.

Vitamin A is part of the thirteen essential vitamins humans need to maintain our health. In particular, vitamin A plays a large role in bone growth, eye health, and overall immunity of the body. Specifically, vitamin A impacts our eyes in the following ways:

• Helps with the formation of rhodopsin, the primary photoreceptor that plays a crucial role in night vision

• Protects the cornea (surface of the eyes)

• Reduces risk of macular degeneration and vision loss

• Increases overall immunity

Because of the crucial role it plays, having vitamin A deficiency (VAD) is dangerous, and is the leading cause of blindness in the world. It is more common in developing countries, especially in young children and pregnant women who have difficulty managing a balanced diet . A spectrum of ocular diseases termed “xerophthalmia” are caused by this deficiency. Some examples of xerophthalmia include:

• Night blindness: difficulty seeing in low light settings

• Conjunctival xerosis: drying of the conjunctiva leading to hazy vision

• Bitot's spots: white spots on the conjunctiva as a result of Corynebacterium xerosis bacteria mixing with keratinized epithelial cells

• Corneal Ulcers: open sore (ulcer) formation as a result of drying

• Keratomalacia: the most severe form of xerophthalmia involved with corneal melting

The key symptom for vitamin A deficiency is loss of vision and in extreme cases, blindness. Patients with this deficiency will often begin to notice changes in their vision in low light settings. If left untreated, vitamin A deficiency can lead to a spectrum of ocular conditions known as xerophthalmia, potentially leading to blindness. Vitamin A deficiency is treated with vitamin supplements, which is often enough to restore the eyes to proper health, however, cannot reverse any permanent scarring from corneal ulcers.

In conclusion, vitamin A is a crucial component in preserving our ocular health. Whether it is through our diet (such as eating carrots) or by consumption of supplements, it is important that we continue to make a conscious effort to maintain healthy levels of vitamin A.

---

References

Awh, C., & Goshe, J. M. (2021, May 29). Xerophthalmia. EyeWiki. Retrieved October 17,

2021, from https://eyewiki.aao.org/Xerophthalmia.

Boyd, K. (2020, October 22). What is vitamin A deficiency? American Academy of

Ophthalmology. Retrieved October 16, 2021, from https://www.aao.org/eye-health/diseases/vitamin-deficiency.

Burke, R. (2017, April 27). The great carrot myth. Calgary Vision Centre. Retrieved October

15, 2021, from https://calgaryvisioncentre.com/news/2017/4/20/the-carrot-myth.

Foster, S. (2019, July 10). The benefits of vitamin A and beta-carotene – Athens OH. Athens

Eye Care - Dr. Shane Foster & Associates. Retrieved October 15, 2021, from https://visionsource-athenseyecare.com/2019/07/10/the-benefits-of-vitamin-a-and-beta-carotene/.

Heiting, G. (2021, September 7). Vitamin A and beta-carotene: Eye benefits. All About Vision.

Retrieved October 16, 2021, from https://www.allaboutvision.com/nutrition/vitamin_a.htm.

Mayo Foundation for Medical Education and Research. (2020, November 13). Vitamin A.

Mayo Clinic. Retrieved October 15, 2021, from https://www.mayoclinic.org/drugs-supplements-vitamin-a/art-20365945.

MediLexicon International. (n.d.). What is beta carotene? What are the benefits? Medical

News Today. Retrieved October 17, 2021, from https://www.medicalnewstoday.com/articles/252758#uses_benefits.