Dietary Total Antioxidant Capacity (TAC) Significantly Reduces the Risk of Site-Specific Cancers: An Updated Systematic Review and Meta-Analysis.

We aimed to evaluate the possible role of dietray TAC against different types of cancers in a systematic review and meta-analyses of observational studies. A literature search of authentic electronic resources had been performed to obtain the relevant studies up to February 2020. Twenty-one studies including nine prospective and twelve case-control studies were included in the current systematic review and meta-analysis. These studies have included 1404297 individuals. Higher TAC categories were associated with 21% reduced risk of colorectal cancer, 27% reduced risk of endometrial cancer, 42% reduced risk of gastric cancer, and 32% reduced risk of pancreatic cancer. In meta-analysis of prospective studies also highest category of TAC was associated with reduced incidence of breast cancer (RR= 0.68; CI: 0.54, 0.86;  = 0.025), colon cancer (RR= 0.92; CI: 0.74, 1.16;  = 0.01), hepatocellular carcinoma (RR= 0.49; CI: 0.35, 0.69;  < 0.001), gastric cancer (RR= 0.65; CI: 0.50, 0.84;  = 0.001), lung cancer (RR= 0.90; CI: 0.85, 0.95;  = 0.001) while increased risk of rectal cancer (RR= 1.02; CI: 0.69, 1.52;  = 0.005). Higher intake of dietary TAC was in association with reduced risk of different types of cancers in meta-analysis of observational studies.