PICO for study inclusion
| Participants (P) | Intervention (I) | Comparison (C) | Outcomes (O) | |
| Inclusion | Men and women of any age, ethnicity, geographic area, comorbidities or medication use | Carnosine and related HCDs (beta-alanine, anserine, NAC, etc) supplementation administered in any form (intravenous, intramuscular or oral), alone (pure) or combined with other intervention/s, of any dosage and for any duration | Placebo or usual care or any pharmacological or non-pharmacological interventions | All chronic disease risk factors and outcomes including but not limited to metabolic/glycaemic, cardiovascular and cognitive/mental health risk factors and outcomes |
| Exclusion | Studies not in humans | Studies without carnosine and/or HCD supplementation | Studies with no control group | None |
| Study type | RCTs and systematic reviews of RCTs | |||
| Language | No limit | |||
| Year of publication | No limit | |||
HCDs, histidine-containing dipeptides; NAC, N-acetylcarnosine; PICO, Population, Intervention, Comparison, Outcomes framework; RCT, randomised controlled trial.