RESEARKA

Population specificity constrains external validity across the corpus. The two RCTs enrolled older adults (Ramos-Hernandez 2026) and adults aged 60–80 with mild cognitive impairment or cardiometabolic disorders (Borda 2025); neither included younger, healthy, or racially diverse cohorts. Observational studies such as Mungan 2026 (multiple sclerosis) and Sundermann 2026 (early Alzheimer's disease) examined disease-specific populations whose biomarker trajectories may not generalize to community-dwelling adults. Furthermore, the systematic reviews and meta-analyses in the corpus (Lyra 2026; Singh 2026; Msigwa 2026) pooled heterogeneous study populations without stratification by age, sex, or comorbidity burden, limiting precision for sub-group inference. Without trials enrolling non-diabetic, non-frail adults, the synthesis cannot determine whether the observed biomarker effects hold in lower-risk populations.

Citation Support

• source_1 Lyra 2026
• source_2 Ramos-Hernandez 2026
• source_3 Davidson 2025
• source_4 Alonso 2026
• source_5 Skerrett 2026