Age-related macular degeneration (AMD) is a progressive condition that affects millions as they age, leading to vision loss and impacting quality of life. Research over the past two decades has increasingly pointed to melatonin, a hormone known for its role in regulating sleep, as a potential protector of eye health. Multiple studies from 2006 to 2025 suggest that melatonin may provide significant benefits for the eyes, particularly against age-related ocular conditions.
1. Overview of Evidence Supporting Melatonin's Role in Eye Health
Several studies indicate that melatonin exhibits protective properties due to its antioxidant, anti-inflammatory, and circadian-regulating effects. This structured analysis compiles substantial findings on melatonin’s potential benefits for age-related eye health.
2. Key Studies and Findings
A. Reduced AMD Risk and Slower Progression
Recent studies have demonstrated a significant correlation between melatonin use and a reduced risk of developing AMD, as well as slower disease progression in those already diagnosed:
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A July 29, 2024 study from the Cleveland Clinic analyzed over 120,000 patients aged 50 and older, revealing that those who utilized melatonin had a remarkable 42% lower risk of developing AMD (Risk Ratio [RR] 0.42) and a 56% reduced risk of progression to advanced AMD for existing cases. This finding aligns with a previous study from China, which indicated that a nightly intake of 3 mg of melatonin over three months could decelerate AMD progression.
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A June 6, 2024 retrospective cohort study (121,523 patients free of AMD at baseline) affirmed melatonin's protective effects with consistent results in age subgroups: patients aged 60 or older saw a risk reduction (RR 0.36) and those 70 or older had an even lower risk (RR 0.35). These results were bolstered by propensity score matching, which minimized confounding variables, thus strengthening the argument for causality.
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A 2023 study published in the Journal of Clinical Medicine involving 200 participants taking 5 mg of melatonin nightly for 12 months noted a 24% reduction in AMD risk. It's important to acknowledge the study's observational design, as causative relationships require further clinical trials.
B. Mechanisms of Action
Research has identified several mechanisms through which melatonin exerts its protective effects on eye health:
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Antioxidant Properties: According to a 2016 source, melatonin accumulates in retinal mitochondria, neutralizing free radicals that can lead to oxidative stress and damage to retinal pigment epithelium (RPE) cells — crucial for retinal health. A more recent study from February 27, 2025 found that melatonin also counters ferroptosis, a form of iron-dependent cell death in RPE cells, utilizing the PI3K/AKT/MDM2/P53 signaling pathway to address oxidative damage characteristic of dry AMD.
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Circadian Rhythm Regulation: Highlighted in an article from June 11, 2024, melatonin helps regulate retinal circadian rhythms, which are essential for stabilizing intraocular pressure and maintaining retinal function. Interestingly, patients with AMD often exhibit low melatonin levels in their blood and tears, suggesting a potentially vital role this hormone plays in ocular health.
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Anti-Inflammatory and Immunomodulatory Effects: A 2025 study using a mouse model indicated that melatonin has anti-inflammatory properties that could protect against retinal cell death. The research demonstrated that melatonin enhanced the proliferation of regulatory T cells (Tregs) and guided microglia toward anti-inflammatory states.
C. Clinical and Expert Endorsements
Several leading experts in the field have acknowledged the potential of melatonin in combating AMD:
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Theodore Leng, MD, from Stanford, highlighted melatonin’s antioxidant benefits for AMD in a 2023 LinkedIn post.
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Dr. John Hovanesian, in a March 10, 2025 YouTube video, discussed the Cleveland Clinic's findings and their implications for reducing AMD risk through melatonin usage.
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Hejin Jeong from Case Western noted in a 2025 report that melatonin counteracts oxidative damage and choroidal neovascularization, a hallmark of advanced AMD.
3. Safety, Dosage, and Comparisons
When considering melatonin for eye health, dosage and safety are crucial:
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Dosage: Typical melatonin doses range from 1–5 mg nightly, with evidence supporting the use of 3–5 mg. While the maximum safe dose is 10 mg, long-term low-dose use generally is considered safe. However, the optimal dosage for eye health remains to be defined consistently.
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Safety: While melatonin is largely regarded as safe for long-term use in low doses, an assessment of individual health conditions and possible medication interactions is vital.
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AREDS2 Comparison: The AREDS2 formula has shown to reduce AMD progression by 25% in intermediate cases. In contrast, melatonin functions through varied multi-target mechanisms (including antioxidant and anti-inflammatory effects) which may enhance existing therapies.
4. Limitations and Future Directions
Despite the promising findings, there are limitations that researchers must address:
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Observational Bias: A significant number of studies have been observational, raising questions about causality.
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Need for Trials: Researchers consistently advocate for well-structured randomized controlled trials (RCTs) to firmly establish causative relationships and clarify appropriate dosing guidelines.
5. Practical Recommendations
If considering melatonin for eye health, it is crucial to:
- Consult a Doctor: Melatonin can interact with various medications (e.g., blood thinners), making professional guidance essential.
- Implement Lifestyle Synergy: In addition to melatonin, incorporating at least 5 oz of daily fruit intake (linked with a 15% lower AMD risk) and reducing blue-light exposure can further protect eye health.
- Monitoring: Patients at risk for AMD should regularly consult with ophthalmologists to track disease progression.
6. Conclusion
Emerging evidence from 2006 to 2025 underscores the potential of melatonin to protect against age-related macular degeneration through its antioxidant, anti-inflammatory, and circadian-regulating actions. While it should not be viewed as a cure, melatonin presents a promising option for preventive and adjunctive therapy, particularly in managing dry AMD. Continued research will be crucial in elucidating its role in clinical practice.
For those interested in learning more about the latest findings in ocular health and melatonin, additional resources can be found at:
