Dry, irritated eyes can itch and burn, causing significant discomfort. In severe cases, dry eyes can cause problems with vision and even lead to eye damage. Unfortunately, the condition is common; one study of patients with a mean age of 59 found more than half of the studied individuals had dry eye disease (DED). As we get older, dry eyes become more prevalent and often more problematic.

What Causes Dry Eye Disease?

DED is typically considered a chronic and progressive condition, meaning, over time, it continues to worsen. The direct cause is attributed to reduced tears produced by tear glands in the eye. As tear levels decrease, the protective tear film is lost, which can cause damage to the surface of the eye.

Risk factors that increase the incidence of dry eye include age, female sex, computer monitor use, eye surgery, contact lens use, diabetes, high blood pressure, heart disease, glaucoma, thyroid disease, arthritis, depression, sleep apnea, and some medications. Some of these conditions, like diabetes and high blood pressure, are potentially reversible, which could help improve dry eye symptoms.

One of the most common causes of dry eyes is meibomian gland dysfunction (MGD). The meibomian glands line both the upper and lower eyelids, producing oil that helps prevent the evaporation of tears. In some cases, these glands become clogged and no longer effectively produce their oil film. If MGD is the cause of dry eyes, it should be addressed by an eye doctor because expressing the glands can often help to restore their function. For any individual with new onset dry eye symptoms, an evaluation from an eye doctor is needed to understand the underlying cause.

Natural Dry Eye Treatments

Natural treatments for dry eyes fall into two basic categories: treatments used topically on the eye and oral supplements. Eye treatments are typically lubricants that attempt to replace the missing tear film.

1. Eye Drops

Topical treatments are often as simple as washing the eyelids and warm compresses to help tear flow. Standard eye drops can also help, although they should be lubricant eye drops, not eye drops, for reducing redness. Some individuals also get dry and irritated eyes from preservatives found in commercial eye drops and may need preservative-free formulations. In particular, research suggests that benzalkonium-chloride-preserved eye drops may cause irritation with long-term use and should likely be avoided.

2. Hyaluronate

Other topical eye drop formulations for dry eye that appear to hold promise include hyaluronate (a buffered form of hyaluronic acid). Hyaluronate is a natural compound that is a component of connective tissue that acts as a lubricant. When administered in eye drops, it appears to provide significant reductions in symptoms. Comparisons with standard formulations have often shown a preference for hyaluronate-containing formulations, but a recent analysis did not find the differences to be statistically significant. Regardless, hyaluronate drops are an option to help reduce dry eye symptoms.

3. Licorice

Licorice is an herb with a well-known anti-inflammatory effect. One of the main active components found in licorice is glycyrrhizin. In a pilot study, approximately 70% of patients with dry eye had improvements with glycyrrhizin-containing eye drops. However, one individual reported an allergic response and had to discontinue use. Other studies have also used glycyrrhizin in combination with other lubricants for dry eye symptoms to good effect.

4. Castor Oil

Castor oil has long been a home remedy for numerous health concerns, although the latest data suggest that it may be too harsh as an oral treatment for constipation. For eye health, however, castor oil appears to hold promise. Applied topically to the eye as an eye drop, castor oil improved tear film while decreasing symptoms of dry eye. It also may be helpful for eye symptoms in some cases through its antimicrobial properties. In addition, castor oil can help treat MGD and reduce inflammation, helping to soothe irritated tissues.

5. Vitamin A

Vitamin A deficiency is a leading cause of blindness in children in developing countries. When vitamin A is deficient, the eyes may lose their ability to stay lubricated which can result in scarring and blindness. In people who are deficient in vitamin A, oral supplementation will likely be helpful. However, studies have also found that topical vitamin A is useful for the treatment of DED. Vitamin A ointment was found to improve dry eye symptoms while improving tear film. Topical vitamin A was also effective for reversing cellular damage seen in cases of DED.

Supplements for Dry Eyes

Oral treatments work by trying to decrease inflammatory and other disease parameters to improve tear production.

1. Omega-3

Omega-3 fatty acids have been well studied with respect to their benefits for dry eyes. A short-term study had individuals consume a modest amount of omega-3 fats daily: 360 mg of eicosapentaenoic acid (EPA) and 240 mg of docosahexaenoic acid (DHA). All patients in the study were struggling with dry eye symptoms, with treated patients taking omega-3 fats for one month. At the end of the supplementation period, tear-film evaporation time had increased, while the eye-surface disease index decreased from severe to moderate in patients taking omega-3 fats.

A more recent study treated patients with DED with either krill oil, fish oil, or placebo. Krill oil and fish oil are both sources of omega-3 fats. Dosing was approximately 1000 mg per day of EPA and 500 mg of DHA for three months. While both forms of omega-3 fats provided benefits, krill oil was superior to fish oil for reducing symptoms and inflammation.

Overall, a meta-analysis of the studies on omega-3 supplementation for dry eye concluded that they effectively improve both signs and symptoms. Based on the findings, the authors suggest that omega-3 fatty acids may be an effective treatment for DED.

2. Sea Buckthorn Oil

Sea buckthorn is a unique herb rich in antioxidants and certain fats, including omega-7 fatty acids. While most people have heard of omega-3 and omega-6 fats, omega-7 fatty acids are a type of monounsaturated fat, similar to the type of fat found in olive oil. As research into omega-7 fats has grown, they have shown benefits for eye health.

Cold weather often worsens dry eye symptoms. In a study of men and women with dry eyes in late fall and early winter, sea buckthorn oil supplementation improved redness significantly with trends for improvements in burning. In addition, sea buckthorn oil helped to decrease the tear-film worsening that occurs with colder weather.

A study in mice found that sea buckthorn oil and isolated omega-7 oil both restored tear production. The authors concluded that the main therapeutic component in sea buckthorn oil is likely the omega-7 component and that it may be a potent treatment for the prevention of dry eye.

While not as well studied for DED, it is worth noting that macadamia nuts are also a rich source of omega-7 fatty acids.

3. Vitamin D

Vitamin D appears to have a role in the treatment of DED. Numerous studies have found correlations between low vitamin D levels and dry eye. Lower vitamin D levels have been shown to correlate with dry eye symptoms and tear breakup time.

While correlations are interesting, clinical studies can provide stronger evidence of actual benefits. A study on vitamin D supplementation in patients with stubborn dry eye symptoms that were not responding to standard treatment also found positive results. Vitamin D improved redness and symptom severity significantly in treated subjects.

4. Probiotics

Research continues to uncover surprising connections between gut health and overall well-being. And the relationship between gut health and eye health is one clear example. While a lot of the initial data is in animal studies, human trials have also shown benefits with probiotics for DED. In one trial, subjects with dry eyes were given both a probiotic supplement and prebiotic fiber. The combination reduced symptoms significantly better than placebo.

A separate study treated patients with DED with either a combination of the probiotic yeast Saccharomyces boulardii and probiotic bacteria Enterococcus faecium or a placebo. The combination product was found to decrease symptoms better than placebo, improving tear film and tear production.

Safety

Any treatment that is used on or in the eye should be both formulated properly and sterile so as not to cause irritation or infection. Any of the topical treatments mentioned should only be used if they are purchased from a reputable source and formulated specifically for use in the eye.

Conclusion

Dry eyes, especially when severe, can cause significant suffering. Individuals struggling with DED often have a loss in the quality of their life. Fortunately, a number of treatments have been shown to be helpful for dry eyes. After an evaluation by an eye doctor to understand the underlying cause, both topical and oral natural treatments may improve symptoms and help to address aspects of the underlying disease process.

References:

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