Dry eye disease (DED) is a common chronic condition characterized by ocular surface discomfort and tear film instability. Evaporative DED associated with meibomian gland dysfunction (MGD) is a frequent phenotype and is often driven by inflammatory mechanisms. This randomized, double-blind, placebo-controlled trial evaluates whether an oral microbiome-focused food supplement improves dry eye symptoms and objective clinical signs compared with placebo over 8 weeks in adults with moderate evaporative DED due to MGD.

Participants with moderate evaporative DED associated with MGD will be randomized 1:1 to receive either a microbiome-focused oral food supplement or matching placebo for 8 weeks. The primary endpoint is change in Ocular Surface Disease Index (OSDI) from baseline to Week 8 and at 16 week follow-up. Key secondary endpoints include changes in tear film breakup time (TBUT), Schirmer I test, and ocular surface staining. Safety and tolerability will be assessed throughout the study. Standard supportive care (e.g., preservative-free artificial tears) will be permitted if kept stable and documented.

Incluison criteria:

1. Adults aged 18-65 years.

2. Participants were required to meet all of the following criteria:

   • Presence of dry eye symptoms, defined as an OSDI-6 summed score ≥4 at baseline.
   • Objective evidence of tear film homeostasis loss in at least one eye, defined by at least one of the following:

   A: Non-invasive tear break-up time (NIBUT) <10 seconds, and/or

   B: Ocular surface fluorescein staining consistent with DED, defined as:

   • Corneal and/or conjunctival fluorescein staining graded ≥1 using the Oxford scale, and/or
   • Lid wiper epitheliopathy graded ≥1 using the Korb grading system

3. Ability to provide written informed consent and comply with study procedures.

4. Willingness to maintain stable use of permitted background measures (e.g., preservative-free artificial tears) and to avoid initiating new probiotics/prebiotics during the trial.

Exclusion criteria:

1. Sjögren syndrome or other active systemic autoimmune disease with significant ocular involvement (investigator judgment).
2. Active ocular infection, acute blepharitis flare, or active allergic conjunctivitis requiring escalation of therapy.
3. Ocular surgery (including cataract) or significant ocular trauma within 6 months prior to the Screening Visit.
4. Previous LASIK or any prior corneal surgery at any time.
5. Use of topical cyclosporine, lifitegrast, or topical ocular corticosteroids within 6-8 weeks prior to baseline, or planned initiation during the treatment period.
6. Punctal plugs within 3 months prior to baseline or planned during the study.
7. Use of glaucoma medications or history of glaucoma filtering surgery.
8. Contact lens use within 30 days prior to baseline or planned use during the study.
9. Systemic isotretinoin within 6 months prior to baseline.
10. Systemic antibiotic use within 8 weeks prior to baseline.
11. Eyelid abnormalities affecting lid function (e.g., lagophthalmos, blepharospasm, ectropion, entropion, severe trichiasis).
12. Active thyroid eye disease (thyroid orbitopathy) or clinically significant ocular surface exposure secondary to thyroid dysfunction.
13. Extensive ocular surface scarring or conditions compromising ocular surface integrity, including Stevens-Johnson syndrome, prior chemical burn, recurrent corneal erosions, persistent epithelial defects, or prior severe ocular trauma.
14. Known hypersensitivity to study product ingredients.
15. Any medical or ocular condition that, in the investigator's opinion, would compromise patient safety or study integrity.
16. Pregnancy or breastfeeding (if applicable) or planning pregnancy during the intervention period.
17. Gastrointestinal diseases known to significantly affect digestion, absorption, or intestinal physiology, including but not limited to inflammatory bowel disease, celiac disease, or a history of major gastrointestinal surgery
18. Individuals following restrictive or specialized dietary patterns, including ketogenic, vegan, or similar diets

De-identified individual participant data (IPD) underlying the results reported in the final publication, including demographic variables, baseline characteristics, outcome measures (e.g., OSDI, NIBUT/TBUT, staining scores, Schirmer, meibography parameters), adverse events, and adherence variables.

Data will be available beginning 6 months after publication and ending 5 years after publication.

Access will be provided to qualified researchers with a methodologically sound proposal. Requests must include a brief analysis plan and will be reviewed by the study steering committee. Data will be shared under a data use agreement that prohibits re-identification and requires appropriate citation of the original study.