Calcium and Dairy Products in the Chemoprevention of Colorectal Adenomas: A Systematic Review and Meta-Analysis Publisher Pubmed

Summary: Meta-analysis shows calcium from dairy reduces colorectal adenoma risk by 21%, but supplements don’t. Natural sources may prevent cancer growth. #ColorectalCancer #Nutrition

Emami MH¹ ; Salehi M² ; Hassanzadeh Keshteli A³ ; Mansourian M⁴ ; Mohammadzadeh S¹ ; Maghool F¹
Source: Critical Reviews in Food Science and Nutrition Published:2022

Abstract

The risk of transition to colorectal cancer (CRC) in advanced colorectal adenomas (ACAs) is about 2.5 times higher than the non-advanced ones. This systematic review and meta-analysis was performed to determine the effect of calcium and dairy products on the incidence of CAs and ACAs. Six databases were systematically searched and 37 relevant clinical trials and observational studies involving over 10,964 cases were selected for inclusion. The results showed that calcium consumption reduced the risk of CAs incidence by 8% (RR: 0.92; 95% CI: 0.89–0.96), and calcium intake as a food and dairy product reduced it about 21% (RR: 0.79; 95% CI: 0.72–0.86), and 12% (RR: 0.88; 95% CI: 0.78–0.98), respectively. However, calcium supplementation did not show a significant effect on CAs incidence (RR: 0.97; 95% CI: 0.89–1.05). Results also revealed that total calcium intake markedly reduced the risk of ACAs (RR: 0.79; 95% CI: 0.73–0.85) and the risk of recurrence of adenomas about 12% (RR: 0.88; 95% CI: 0.84–0.93). Our results suggest that natural sources of calcium such as dairy products and foods may have more effective role than supplementary calcium in terms of reducing the risk of incidence and recurrence of colorectal adenomas and advanced adenomas. © 2021 Taylor & Francis Group, LLC.