Also known as: Provitamin A, Beta-Carotene (synthetic)
Latest evidence update: 2026-05-24
Strongest in Sample size (95). Held back by Recency (8).
Solid mix of RCTs with some methodological gaps.
Confirmed across many independent studies with significant findings.
Tens of thousands of participants pooled across studies.
Mixed direction across studies.
Mostly pre-2020 research; updates may be needed.
Effect-size tagged on 298 of 310 claims for this supplement. Our research updates daily; remaining claims are pending re-processing.
Areas where research points to a consistent direction of effect. The strength of evidence is graded; the size of the effect is not quantified.
Recommended: Not recommended as supplement
ProtocolEngine provides general health information based on published research. This is not medical advice. Consult a healthcare professional before starting any supplement or health protocol.
May reduce risk of cataracts and support eye health
May lower lung cancer risk in people with high dietary intake, but supplements may increase risk in smokers
May reduce bone loss and fracture risk, particularly in Asian populations and women
May reduce type 2 diabetes risk, with higher blood levels showing stronger protective effects
May support breast cancer survival and reduce breast cancer risk through dietary intake