Abstract
Although it has been proposed that trace minerals have anti-oxidative functions and are related to the control of blood pressure, only a limited number of studies directly address the issue. Thus, the purpose of our study was to assess the intake of copper and manganese, which are trace minerals, and to clarify their relation to blood pressure. In a cross-sectional study, the blood pressure of 640 normotensive adults, from 19 to 69 year-old (320 males and 320 females), was measured, and its correlation with the intake of copper and manganese was assessed using a 24-hour dietary recall method. The average value of the blood pressure was 126.4/80.2 mmHg for the males and 117.8/75.8 mmHg for the females. The daily copper intake was 1.3 mg/day for the males and 1.2 mg/day for the females. For manganese, the daily intake was 4.2 mg/day for the males and 4.1 mg/day for the females. Although the copper intake of all subjects showed a positive correlation with the systolic and diastolic blood pressures, there was no significant correlation when the potential confounding factors were adjusted. The manganese intake of the male subjects had a significantly negative correlation with the systolic blood pressure after adjusting for gender, age, body mass index, and energy intake. In conclusion, the daily manganese intake of the normotensitve adults showed a significantly negative correlation with the systolic blood pressure indicating a possibility of a positive effect of manganese on blood pressure.