Abstract A114: Dietary magnesium and calcium intake and risk of prostate cancer in Caucasian and African American men

Abstract

Abstract Dietary magnesium intake is significantly less in African Americans than Caucasians. Deficiency of magnesium influences immune-inflammatory response and induces oxidative stress that leads to increased cell proliferation and DNA damage. Low magnesium level also increases the physiologic effects of calcium. Therefore, we hypothesize that low dietary intake of magnesium and high calcium intake will increase the risk of developing prostate cancer among African American men. To test this hypothesis, we conducted a pilot case-control study to determine whether deficiency of dietary magnesium and a high calcium intake are associated with an increased risk of prostate cancer. This study included 209 cases with histologically confirmed adenocarcinoma of the prostate (110 African American and 99 Caucasian men). 199 population-based controls were frequency matched by age (±5 years) and race. Risk factor questionnaire and nutrition data were collected via telephone interview. Dietary Assessment was performed using Modified Block-NCI Food Frequency Questionnaire with 129 food items, questions about restaurant intake and vitamin mineral supplementation. Dietary intake was calculated using DIETSYS + Plus version 5.9 dietary analysis program. Nutrition data for 166 cases and 155 controls were available for this analysis. Mean magnesium and calcium intake did not vary significantly between cases and controls. The odds ratios for magnesium was 0.79 (95% CI 0.39–1.61) and for calcium 1.35 (95% CI 0.87–2.09). However, among African Americans, the odds ratio for magnesium was 0.28 (95% CI 0.08–1.05) and for calcium 1.9 (95% CI 1.05–3.40). These preliminary data suggest that high dietary magnesium intake is inversely associated with prostate cancer, while higher calcium intake is associated with increased risk among African American men. These data may have significant public health implications since the identification of African American men deficient of magnesium can be targeted for preventive interventions. Results of this study needs to be confirmed in future studies with larger sample size. Citation Information: Cancer Prev Res 2011;4(10 Suppl):A114.