Dementia is a significant public health problem, affecting 47 million people worldwide in 2015, according to World Health Organization data. It is expected to increase to 75 million in 2030 and reach 132 million in 2050.

Royal jelly is used as a supplement in treating of cancer, hypertension, diabetes and neurodegenerative diseases due to its antioxidant, anti-inflammatory, neuroprotective, cardioprotective, anti-proliferative and anti-fatigue properties. There are preclinical studies on the curative and protective effects of royal jelly on cognitive functions.

This randomized controlled, double-blind clinical trial is aimed to study the effect of oral use of lyophilized royal jelly for 4 weeks on immune system cytokine levels and cognitive functions in individuals aged 55-70 years without any neurological disease diagnosis.

Primary outcome measures are the Mini-Mental State Examination, and the Alzheimer's Disease Assessment Scale-Cognitive Subscale.

Secondary outcome measures are the Geriatric Depression Scale, and serum interleukin-1β, and interleukin-6, and interleukin-10, and tumor necrosis factor-α, and transforming growth factor-β levels.

Volunteers who apply to Bağcılar Medipol Mega University Hospital Neurology Polyclinic will be recruited, and their demographic information will be recorded.

Volunteers who meet eligibility criteria will be randomly divided into three groups considering age, and gender, and BMI, and education level .

Primary and secondary outcome measures will be evaluated in volunteers. The results obtained will be recorded.

Diet recommendations will be made to the volunteers for four weeks. The products detailed in the protocol will be used by the volunteers orally for four weeks on an empty stomach in the morning.

Primary and secondary outcome measures will be reassessed in volunteers on day 28. The results obtained will be recorded.

Obtained results will be evaluated statistically.

Inclusion Criteria:

• Between the ages of 55 and 70,
• Male or female,

Exclusion Criteria:

• History of allergy to bee products
• Known history of lactose allergy
• Diagnosed dementia,
• MMSE score below 21,
• ADAS-Cog score of 12 and above,
• Body Mass Index of 35 and above,
• Be taking any medical medication, herbal product or dietary supplement for dementia, except for those who stopped using it at least 1 month before inclusion in our study,
• Being or having been treated for acute acquired brain injuries such as acute traumatic brain injury, acute onset stroke,
• Being followed up due to inflammatory disease,
• Diagnosis of chronic or acute infection,
• Taking corticosteroids or non-steroidal anti-inflammatory drugs,
• Being or having been treated for a psychotic illness,
• Severe anaemia, vital organ dysfunction or critical illness.

This study employed a rigorous quadruple-blind design, successfully blinding 120 participants, clinicians, laboratory personnel, and statisticians to systematically isolate bias. To prevent unblinding from the active supplement's (LRJ) distinct organoleptic properties, strict masking was applied; active and placebo capsules were manufactured to be identical in appearance, weight, and texture. Additionally, daily capsule counts and administration timings were standardized across all dose groups to prevent dosage guessing. Allocation codes were strictly concealed until database lock and completion of primary analyses, minimizing observer bias. An emergency code-breaking protocol was established but remained unused. Collectively, these stringent procedures ensured high internal validity and methodological robustness.