Effect of Red, Processed, and White Meat Consumption on the Risk of Gastric Cancer: An Overall and Dose⁻Response Meta-Analysis

Abstract

: Whether the risk of gastric cancer varies by the types of meat consumption still remains disputable. The purpose of this meta-analysis was to identify the exact associations that red, processed, and white meat have with gastric cancer. We searched relevant studies in Medline, EMBASE, and the Cochrane Library before November 2018, including cohort and case-control studies. We used random-effect models to estimate the adjusted relative risk (RR), and Egger's tests to evaluate publication bias. Through stepwise screening, 43 studies were included in this analysis (11 cohort studies and 32 case-control studies with 16,572 cases). In a meta-analysis for the highest versus lowest categories of meat consumption, both red (RR: 1.41, 95% confidence interval (CI): 1.21-1.66) and processed (RR: 1.57, 95% CI: 1.37-1.81) meat consumption were positively associated with gastric cancer risk, while white meat consumption was negatively associated with gastric cancer risk (RR: 0.80, 95% CI: 0.69-0.92). In a dose-response meta-analysis, the RRs of gastric cancer were 1.26 (95% CI: 1.11-1.42) for every 100 g/day increment in red meat consumption, 1.72 (95% CI: 1.36-2.18) for every 50 g/day increment in processed meat consumption, and 0.86 (95% CI: 0.64-1.15) for every 100 g/day increment in white meat consumption. The increase of white meat consumption may reduce the risk of gastric cancer, while red or processed meat may increase the risk of gastric cancer. Further studies are required to identify these associations, especially between white meat and gastric cancer.

Keywords: cancer epidemiology; gastric cancer; processed meat; red meat; white meat.

Figure 1

Flow diagram for the selection of studies. A total of 43 studies for quantitative meta-analysis were selected using the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) 2009 flow diagram.

Figure 2

Adjusted relative risks and 95% confidence intervals of gastric cancer for red meat consumption. Squares indicate each study’s relative risks. Horizontal lines indicate 95% confidence intervals. Diamonds indicate the summary relative risks and 95% confidence intervals. (a) Highest versus lowest categories of red meat consumption; (b) dose–response meta-analysis for 100 g/day increase in red meat consumption.

Figure 2

Adjusted relative risks and 95% confidence intervals of gastric cancer for red meat consumption. Squares indicate each study’s relative risks. Horizontal lines indicate 95% confidence intervals. Diamonds indicate the summary relative risks and 95% confidence intervals. (a) Highest versus lowest categories of red meat consumption; (b) dose–response meta-analysis for 100 g/day increase in red meat consumption.

Figure 3

Adjusted relative risks and 95% confidence intervals of gastric cancer for processed meat consumption. Squares indicate each study’s relative risks. Horizontal lines indicate 95% confidence intervals. Diamonds indicate the summary relative risks and 95% confidence intervals. (a) Highest versus lowest categories of processed meat consumption; (b) dose–response meta-analysis for 50 g/day increase in processed meat consumption.

Figure 3

Adjusted relative risks and 95% confidence intervals of gastric cancer for processed meat consumption. Squares indicate each study’s relative risks. Horizontal lines indicate 95% confidence intervals. Diamonds indicate the summary relative risks and 95% confidence intervals. (a) Highest versus lowest categories of processed meat consumption; (b) dose–response meta-analysis for 50 g/day increase in processed meat consumption.

Figure 4

Adjusted relative risks and 95% confidence intervals of gastric cancer for white meat consumption. Squares indicate each study’s relative risks. Horizontal lines indicate 95% confidence intervals. Diamonds indicate the summary relative risks and 95% confidence intervals. (a) Highest versus lowest categories of white meat consumption; (b) dose–response meta-analysis for 100 g/day increase in white meat consumption.

Figure 4

Adjusted relative risks and 95% confidence intervals of gastric cancer for white meat consumption. Squares indicate each study’s relative risks. Horizontal lines indicate 95% confidence intervals. Diamonds indicate the summary relative risks and 95% confidence intervals. (a) Highest versus lowest categories of white meat consumption; (b) dose–response meta-analysis for 100 g/day increase in white meat consumption.