TABLE 1.

PICO for study inclusion

Participants (P)	Intervention (I)	Comparison (C)	Outcomes (O)
Inclusion criteria
Participants ≥18 y	Vitamin D supplementation in the form of vitamin D3 (cholecalciferol) or vitamin D2 (ergocalciferol) at any dose, given orally, daily, weekly, or monthly.	RCTs with the intervention compared to placebo	Triglyceride levels (mg/dL), Total cholesterol levels (mg/dL), LDL-C (mg/dL), and HDL- C (mg/dL)
Exclusion criteria
Participants <18 y	Vitamin D supplements with other vitamin and chemical element supplements; vitamin D supplementation in fortified foods as the amount of vitamin cannot be defined accurately.

Abbreviations: RCT, randomized controlled trial.