Evidence Level
Royal jelly research has been driven primarily by Japanese and East Asian researchers. The unique compound 10-hydroxy-2-decenoic acid (10-HDA) is the most studied bioactive, with demonstrated anti-inflammatory, immunomodulatory, and estrogen-like properties. Asama et al. (2018) published a randomized controlled trial in 42 menopausal women showing 800mg/day royal jelly significantly improved menopausal symptom scores over 12 weeks. Guo et al. (2007) found 6g/day reduced total cholesterol and LDL in a 6-week RCT of 36 mildly hypercholesterolemic adults. Morita et al. (2012) reported improved follicular development in IVF patients receiving royal jelly, though the study was small and non-blinded. For skin health, Park et al. (2011) demonstrated improved hydration and reduced wrinkle depth with oral supplementation. Sugiyama et al. (2012) elucidated immunomodulatory mechanisms including NF-kB inhibition. The major limitations include small sample sizes (typically 20-50 participants), predominance of Japanese populations, short study durations, and heterogeneity in royal jelly preparations and 10-HDA content. Allergy risk is the primary safety concern — multiple case reports document anaphylaxis including fatal outcomes.