Dry eye symptoms are pervasive, affecting roughly 38 million U.S. adults.¹ Symptoms of dry eye disease (DED) impact patients’ quality of life and are a significant burden to not only physical health but also mental health. In fact, patients have compared the impact of moderate-to-severe DED to that of a hip fracture or severe angina. 

DED is a multifactorial, chronic, progressive, inflammatory disease process for which topical therapies are the mainstays of treatment. However, what we consume is proving to have a powerful influence on the symptoms and severity of DED. The Standard American Diet (SAD), which is proinflammatory, now appears to be a major driver of meibomian gland dysfunction and DED.² Therefore, DED treatment should focus on disrupting the vicious cycle of ocular surface inflammation through topical therapies and nutrients that support the ocular surface.

Nutrients That Play a Role in Tear Film Dysfunction

Vitamin A: Deficiency can lead to DED by causing goblet cell loss, mucin deficiency and corneal epitheliopathy. Long-term deficiency may result in metaplasia and the keratinization of the corneal and conjunctival epithelial cells. Supplementation has been shown to be helpful for improving ocular surface damage and DED.³ 

Vitamin C: Present in every ocular tissue at 20x to 30x serum concentration, vitamin C has antioxidant, anti-inflammatory and immunomodulatory functions, which can be helpful for the prevention of DED. It also has a therapeutic role in corneal wound repair. A recent experimental study using a rat model showed that vitamin C improved corneal edema and alleviated inflammation after corneal injury caused by ultraviolet B exposure.³ 

Vitamin D: A potent modulator of the innate and adaptive immune system, vitamin D inhibits corneal inflammation by suppressing the migration of Langerhans cells into the cornea and curbing the excessive production of proinflammatory mediators (i.e., interleukins and tumor necrosis factor-α). Research has established a significant association between low serum concentrations of vitamin D and DED occurrence.^4,5 

Lutein and Zeaxanthin: These antioxidant and anti-inflammatory nutrients defend against free radicals and oxidative stress. They have been shown to modulate gene expression related to inflammation and cytokine production, mitigating the inflammatory response within ocular tissues. They are linked to the reduction of factor D and enzymes associated with the alternative complement activation pathway. They contribute to regulating systemic inflammation.⁶ 

Curcumin: This nutrient restores the balance of the ocular surface by diminishing the presence of reactive oxygen species (ROS), suppressing the expression of inflammatory mediators and enhancing the levels of neurotrophic factors.

Omega-3 Fatty Acids: These healthy fats have been shown in studies to decrease inflammation, increase the quality of the tear film, reduce symptoms of dry eye, promote faster epithelial healing and visual recovery with PRK and help to regenerate corneal nerves.^8,9,10

Gamma-linolenic Acid (GLA): Not all omega-6s are proinflammatory. GLA is known as the most powerful health-promoting omega-6 and is found in evening primrose oil, borage seed oil, hemp oil and black currant seed oil. GLA is elongated to form the biologically activated dihomo-γ-linolenic acid (DGLA), which goes on to form the anti-inflammatory prostaglandin E1 or proinflammatory arachidonic acid (ARA). Research shows GLA can be beneficial in dry eye therapy, but it should not be given without omega-3. Only one enzymatic step is necessary to convert the anti-inflammatory DGLA to proinflammatory ARA; namely, adequate levels of eicosapentaenoic acid (EPA) from omega-3s prevent DGLA to ARA conversion to ensure DGLA forms prostaglandin E1.^11,12

Vitamin B12: A cofactor in DNA synthesis, red blood cell formation, homocysteine metabolism and synthesis of S-adenosylmethionine, vitamin B12 is involved in the functioning of the nervous and immune systems. It has been used in neuropathic pain associated with diabetic neuropathy, trigeminal neuralgia and post-herpetic neuralgia. Recently, the role of neurosensory abnormalities in the pathophysiology of DED has become increasingly recognized. In particular, neuropathic pain due to peripheral nerve damage, central sensitization or both seems to be a common feature of the disease, which may explain the poor correlation between signs and symptoms observed in many DED patients. Recent studies have shown improvement of dry eye symptoms in patients with severe DED, whether combined with neuropathic ocular pain or not, following vitamin B12 supplementation.^13,14,15 

Evidence-based supplementation of specific nutrients is an effective addition to topical therapies for DED. Resources such as the Ocular Wellness & Nutrition Society,¹⁶ a professional society dedicated to the science of nutrition, provide courses for doctors to become more proficient in using food and nutrients to mitigate the course of disease.

References:

1. Karpecki PM, Nichols KK, Sheppard JD. Addressing excessive evaporation: an unmet need in dry eye disease. Am J Manag Care. 2023 Oct;29(13 Suppl):S239-S247. doi:10.37765/ajmc.2023.89448
2. Markoulli M, Ahmad S, Arcot J, et al. TFOS Lifestyle: Impact of nutrition on the ocular surface. Ocul Surf. 2023 Jul;29:226-271. doi:10.1016/j.jtos.2023.04.003
3. Hyon JY, Han SB. Dry eye disease and vitamins: a narrative literature review. Appl Sci. 2022;12(9):4567. doi:10.3390/app12094567
4. Rolando M, Barabino S. Dry eye disease: what is the role of vitamin D? Int J Mol Sci. 2023 Jan;24(2):1458. doi:10.3390/ijms24021458
5. Karaca EE, Kemer ÖE, Özek D, Berker D, Nasiroglu Imga N. Clinical outcomes of ocular surface in patients treated with vitamin D oral replacement. Arq Bras Oftalmol. 2020 Aug;83(4):312-317. doi:10.5935/0004-2749.20200043
6. Addo EK, Bernstein PS. Carotenoids in eye health. Ocular Health and Wellness Supplement 2024. Accessed January 15, 2025. https://ocularnutritionsociety.org/wp-content/uploads/2024/08/2023_OcularHealthandWellness_eResource_0923_lo-1-1.pdf
7. Radkar P, Lakshmanan PS, Mary JJ, Chaudhary S, Durairaj SK. A novel multi-ingredient supplement reduces inflammation of the eye and improves production and quality of tears in humans. Ophthalmol Ther. 2021 Sep;10(3):581-599. doi:10.1007/s40123-021-00357-y
8. Epitropoulos AT, Donnenfeld ED, Shah ZA, et al. Effect of oral re-esterified Omega-3 nutritional supplementation on dry eyes. Cornea. 2016 Sep;35(9):1185-1196. doi:10.1097/ICO.0000000000000940
9. Ong NH, Purcell TL, Roch-Levecq A-C, et al. Epithelial healing and visual outcomes of patients using omega-3 oral nutritional supplements before and after photorefractive keratectomy: a pilot study. Cornea. 2013 Jun;32(6):761-765. doi:10.1097/ICO.0b013e31826905b3
10. He J, Bazan HEP. Omega-3 fatty acids in dry eye and corneal nerve regeneration after refractive surgery. Prostaglandins Leukot Essent Fatty Acids. 2010 Apr-Jun;82(4-6):319-325.
11. Vasquez A. Reducing pain and inflammation naturally. Part 2: new insights into fatty acid supplementation and its effect on eicosanoid production and genetic expression. Nutritional Perspectives: J Counc Nutr Am Chiro Assoc. 2005;28(1):5-16.
12. Hom MM, Asbell P, Barry B. Omegas and dry eye: more knowledge, more questions. Optom Vis Sci. 2015 Sep;92(9):948-956. doi:10.1097/OPX.0000000000000655
13. Belmonte C, Nichols JJ, Cox SM, et al. TFOS DEWS II pain and sensation report. Ocul Surf. 2017 Jul;15(3):404–437. doi:10.1016/j.jtos.2017.05.002
14. Ozen S, Ozer MA, Akdemir MO. Vitamin B12 deficiency evaluation and treatment in severe dry eye disease with neuropathic ocular pain. Graefe’s Arch Clin Exp Ophthalmol. 2017 Jun;255(6):1173–1177. doi:10.1007/s00417-017-3632-y
15. Pellegrini M, Senni C, Bernabei F, et al. The role of nutrition and nutritional supplements in ocular surface diseases. Nutrients. 2020 Mar;12(4):952. doi:10.3390/nu12040952.
16. Ocular Wellness & Nutrition Society. Homepage. Accessed January 21, 2025. https://ocularnutritionsociety.org/

This editorial content was supported via unrestricted sponsorship.