Circulating Lycopene and β-Carotene Levels Are Inversely Associated with Carotid Intima-Media Thickness: A Systematic...

Area of Science:

• Cardiovascular Health and Nutrition Science
• Biomarkers of Atherosclerosis
• Antioxidant and Vascular Biology

Background:

• Carotid intima-media thickness (IMT) is a key indicator of subclinical atherosclerosis and cardiovascular risk.
• Carotenoids, like lycopene and beta-carotene, are investigated for their antioxidant properties in preventing vascular damage.
• Existing population studies on carotenoids and IMT show inconsistent results.

Purpose of the Study:

• To systematically review and meta-analyze the association between circulating lycopene and beta-carotene levels and carotid IMT.
• To explore potential sex-specific effects in the general adult population.
• To identify potential modifiers of these associations, including cardiovascular risk factors.

Main Methods:

• Systematic literature search of PubMed, Scopus, and Web of Science up to March 2025.
• Inclusion of observational and experimental studies reporting cross-sectional associations between plasma carotenoids and IMT.
• Random effects models used for pooled odds ratios (ORs) and confidence intervals (CIs); subgroup and meta-regression analyses performed.

Main Results:

• Thirteen studies (n=9131) were included; eight were eligible for meta-analysis.
• Higher lycopene levels significantly correlated with lower IMT (OR=0.70), with a stronger effect in men (OR=0.62) than women (OR=0.74).
• Beta-carotene showed a marginal association with IMT (OR=0.96); systolic blood pressure, BMI, and LDL cholesterol modified these relationships.

Conclusions:

• Elevated serum lycopene concentrations are inversely associated with carotid IMT, suggesting a protective role in vascular health.
• The inverse association between lycopene and IMT appears more pronounced in men, indicating potential sex-specific effects.
• Beta-carotene also shows an inverse association, though less pronounced, with IMT.