2.2. Study Design, Recruitment, and Randomization
SKIN, RECRUITMENT
This prospective, double-blind, randomized controlled trial was conducted in the greater Sacramento area at Integrative Skin Science and Research (Sacramento, CA, USA). Methods of recruitment included local dermatology clinics and social media advertising. The study protocol and consent were reviewed and approved by the Allendale Institutional Review Board (Protocol ID: SYW_01) and registered at In total, 135 individuals were assessed for eligibility and 44 participants were randomized to either SPII or casein. A CONSORT diagram is presented in 