The Role of Garlic (Allium sativum) in Colorectal Cancer Prevention: A Systematic Review of Epidemiological Studies

Abstract

Introduction: Dietary factors play a significant role in the etiology of colorectal cancer (CRC). High consumption of garlic has been hypothesized to reduce CRC risk due to its rich content of organosulfur compounds. This review evaluates the epidemiological evidence for this association.

Methods: We conducted a systematic search of PubMed and Web of Science for case-control and cohort studies. Studies that assessed the consumption of raw or cooked garlic and reported the risk of colorectal cancer, colon cancer, or rectal cancer were included for meta-analysis.

Results: The meta-analysis of 21 epidemiological studies showed a consistent and statistically significant inverse association. Individuals in the highest category of garlic consumption had an approximately 30% lower risk of colorectal cancer compared to those in the lowest category.

Discussion: The large body of epidemiological evidence supports a protective role for high garlic consumption against the development of colorectal cancer. This is likely mediated by the anti-proliferative and pro-apoptotic effects of its organosulfur compounds.

Conclusion: High garlic consumption is associated with a significantly lower risk of developing colorectal cancer.