Julie Poteet, OD, MS, CNS, FOWNS

Dry eye disease, more aptly described as tear film dysfunction, is defined by The Dry Eye Workshop (DEWS) II as a multifactorial disorder of the tears and ocular surface. It is associated with symptoms of discomfort, visual disturbance and tear film instability, and is accompanied by increased osmolarity of the tear film and inflammation of the ocular surface.¹

It is well established that the tear film is part of a larger ocular surface ecosystem comprising the lids and their adnexa; the blink reflex and lacrimal drainage system; the lacrimal and accessory glands; and the epithelia of the cornea and conjunctiva. These structures function in an integrated manner, coordinated by a complex interplay of neural, humoral, endocrine, vascular and immune system input.² Homeostasis of the ocular surface ecosystem is further influenced by the environment, the systemic health of the individual and medications.² Although multifactorial in cause, sustained inflammation is the underlying key mechanism of tissue damage in dry eye disease.

Oral omega 3s have been prescribed for dry eye symptoms for years because studies have shown that they decrease ocular surface inflammation³; reduce symptoms of dry eyes³; increase the quality of the tear film³; promote faster epithelial healing and visual recovery with PRK⁴; and help regenerate corneal nerves.⁵ In a 2023 systematic review and meta-analysis of 19 randomized controlled trials that looked at omega 3 intake and dry eye disease management, the authors concluded that omega 3s significantly alleviated symptoms confirmed by dry eye scores, tear break-up time, Schirmer testing, osmolarity and corneal fluorescein staining with statistical significance across sensitivity analyses.⁶

However, not all trials have shown a benefit. The 2018 DREAM study—a prospective, multi-center, double-masked, randomized controlled trial of more than 500 patients—found omega 3 supplements to be no more effective than placebo in dry eye disease.⁷ The trial used a high-dose triglyceride form of omega 3s, and the results have been the topic of much debate. Many practitioners have changed the way they practice because of the results of the DREAM study, and when patients search the internet to see whether fish oil is good for dry eyes, they get conflicting results from credible sources. New data from several clinical trials also shows an elevated risk of atrial fibrillation in certain patient populations taking supplemental fish oil.^8,9

Fish oil supplements are not standardized and may differ in quality and content across brands. In a recent study by researchers at George Washington University, 72 of the most popular omega 3 supplement brands were tested for rancidity using the recommended rancidity limits by the Global Organization for EPA and DHA Omega-3s (GOED), a global trade group that represents omega 3 manufacturers.¹⁰ The results were shocking. The researchers found that 68% of the flavored and 13% of the unflavored omega 3 supplements exceeded the total oxidation value (TOTOX) upper limit set by GOED. It is worth pointing out that ingesting rancid oils is pro-inflammatory and should be avoided.

The good news is that other nutrients have been shown to decrease ocular surface inflammation and support a healthy ocular surface. Overall dietary pattern is more important than single nutrients because nutrients in combination can have synergistic effects. For example, the benefits of a Mediterranean diet for dry eyes are well established.¹¹ Recent clinical trials have shown that multi-ingredient formulations of nutrients that act synergistically can also improve ocular symptom severity and tear production in patients with dry eye disease.^12-14 In a double-blind, placebo-controlled, multicenter, randomized controlled trial published in Frontiers in Ophthalmology in April 2024, a novel blend of four active ingredients in supplement form was shown to successfully treat dry eyes.¹⁴ The oral nutraceutical blend of lutein, zeaxanthin, curcumin and vitamin D3 increased tear volume and stability, reduced tear osmolarity, improved ocular surface structure with less inflammation and reduced dry eye discomfort.¹⁴ With nutrients, the whole is often greater than the sum of the parts.

Practitioner’s Notes:

As an eye care provider and nutritionist, I have been “prescribing” (vs. simply recommending) omega 3s for ocular and systemic health for more than 20 years. Science strongly supports the need for omega 3s in our diets for optimal health and wellness, and I will continue to prescribe quality omega 3s that have proven track records for efficacy and safety while also educating my patients. Our patients need to understand why we are asking them to purchase a specific brand vs. whatever is cheapest at the store. By giving patients the “why” behind our recommendations, they are much more likely to be compliant with their treatment plans.

References:

1. The definition and classification of dry eye disease: report of the Definition and Classification Subcommittee of the International Dry Eye Workshop (2007). Ocul Surf. 2007 Apr;5(2):75-92. doi:10.1016/s1542-0124(12)70081-2
2. Gipson IK. The ocular surface: the challenge to enable and protect vision: the Friedenwald lecture. Invest Ophthalmol Vis Sci. 2007 Oct;48(10):4390; 4391-4398. doi:10.1167/iovs.07-0770
3. 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
4. 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
5. 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.
6. Wang W-X, Ko M-L. Efficacy of omega-3 intake in managing dry eye disease: a systematic review and meta-analysis of randomized controlled trials. J Clin Med. 2023;12(22):7026. doi:10.3390/jcm12227026
7. Dry Eye Assessment and Management Study Research Group, Asbell PA, Maguire MG, Pistilli M, et al. n-3 fatty acid supplementation for the treatment of dry eye disease. N Engl J Med. 2018 May;378(18):1681-1690.
8. Huh JH, Jo SH. Omega 3 fatty acids and atrial fibrillation. Korean J Intern Med. 2023 May;38(3):282-289. doi:10.3904/kjim.2022.266
9. Curfman G. Omega 3 fatty acids and atrial fibrillation. JAMA. 2021 Mar;325(11):1063. doi:10.1001/jama.2021.2909
10. Hands JM, Anderson ML, Cooperman T, Frame LA. A multi-year rancidity analysis of 72 marine and microalgal oil omega 3 supplements. J Diet Suppl. 2024;21(2):195-206. doi:10.1080/19390211.2023.2252064
11. Molina-Leyva I, Molina-Leyva A, Riquelme-Gallego B, Cano-Ibáñez N, Garcia-Molina L, Bueno-Cavanillas A. Effectiveness of Mediterranean diet implementation in dry eye parameters: a study of PREDIMED-PLUS trial. Nutrients. 2020 May:12(5):1289. doi:10.3390/nu12051289
12. Kan J, Wang M, Liu H, et al. Botanical formula improves eye fatigue and dry eye: a randomized, double-blind, placebo-controlled study. Am J Clin Nutr. 2020 Aug;112(2):334-342. doi:10.1093/ajcn/nqaa139
13. Liu K, Chan YK, Peng X, et al. Improved dry eye symptoms and signs of patients with meibomian gland dysfunction by a dietary supplement. Front Med (Lausanne). 2021 Nov;8:769132. doi:10.3389/fmed.2021.769132
14. Gioia N, Gerson J, Ryan R, et al. A novel multi-ingredient supplement significantly improves ocular symptom severity and tear production in patients with dry eye disease: results from a randomized placebo-controlled clinical trial. Front Med (Lausanne). 2024 Apr;4:1362113. doi:10.3389/fopht.2024.1362113

Julie Poteet, OD, MS, CNS, FOWNS, is an optometrist with 26 years of experience practicing in Acworth, GA. She specializes in pediatric vision care and ocular nutrition, and is a certified nutrition specialist with a masters of science in human nutrition and functional medicine.