Dietary Intakes of Calcium, Iron, Magnesium, and Potassium Elements and the Risk of Colorectal Cancer: a Meta-Analysis

Abstract

The purpose of this study was to analyze the existing studies and to investigate the relationship between the risk of colorectal cancer (CRC) and intakes of four individual dietary elements calcium (Ca), iron (Fe), magnesium (Mg), and potassium (K). All relevant articles in both Chinese and English were searched and collected from PubMed, Web of Science, and Chinese National Knowledge Infrastructure databases up to December 17, 2017. There were 29 eligible literatures selected for further meta-analysis, including 14 cohort studies and 15 case-control studies. The meta-analysis of cohort studies indicated that the high intakes of dietary Ca and Mg were negatively associated with the risk of CRC, as the hazard ratios (HR) were 0.76 (95% confidence interval (CI) 0.72, 0.80) and 0.80 (95% CI 0.73, 0.87), respectively. Nevertheless, high intake of dietary heme Fe was positively correlated to the incidence of colon cancer (HR = 1.01, 95% CI 0.82, 1.19) and rectal cancer (HR = 1.04, 95% CI 0.67, 1.42). A meta-analysis of case-control studies indicated that high intakes of dietary Ca, Mg, and K were negatively related with the occurrence of CRC, because the odds ratios (OR) were 0.36 (95% CI 0.32, 0.40), 0.80 (95% CI 0.63, 0.98) and 0.97 (95% CI 0.74, 1.21), respectively. However, high Fe intake from diet was positively correlated with the rising increasing of CRC (OR = 1.04, 95% CI 0.91, 1.18). More research is needed to indicate the risk relationship between element intake and CRC.

Prospective Association of Serum and Dietary Magnesium with Colorectal Cancer Incidence

“…In addition, we observed a stronger association of serum magnesium with rectal cancer than with colon cancer. This association was not observed in our analysis of dietary magnesium, while meta-analyses of prospective studies have found significant associations of dietary magnesium with colon, but not rectal cancer (10). Serum magnesium has not previously been studied in relation to colon or rectal cancer, and further research is needed to confirm or refute the stronger association of serum magnesium with rectal than colon cancer observed here.…”

Overexpression of MAGT1 is associated with aggressiveness and poor prognosis of colorectal cancer

“…Notably, a growing body of epidemiological studies determined that high magnesium intake is associated with a lower incidence of CRC (23)(24)(25), which seems to contradict the aforementioned association between MAGT1 and CRC. However, due to the crucial role of MAGT1 in the regulation of NK and CD8 + T-cells by mediating transient Mg 2+ influx (7,21), this discrepancy may be explained by the high magnesium intake that may reduce the incidence of CRC by activating cytotoxic T-cells.…”

Associations between nutritional factors and KRAS mutations in colorectal cancer: a systematic review

“…In fact, studies in animals have indicated a protective effect of dietary calcium, which binds bile acids in the bowel lumen, inhibiting their proliferative and the carcinogenic effects [86,87], and reduces the number of mutations in the KRAS gene of the rat [88]. Also, a recent metaanalysis including 14 cohort studies and 15 case-control studies, suggests that higher intakes of dietary Calcium may help to reduce the risk of CRC slightly [89].…”