Food & Nutrition

The concentration of nutritionally important minerals is under homeostatic control, however, physical activity and age may change the plasma levels of these as per altered metabolic requirement. Stratified cluster sampling was used to select participants (n=360) belonging to three different activity groups -Sedentary, Moderately active and highly active  which were further divided into six age groups (18-20, 21-25, 26-30, 31-35, 36-40, and 41-45y). Body composition was analyzed using bioelectrical impedance. Fasting blood samples were taken and plasma samples was separated by centrifugation and stored at -80°C until analysis. Plasma samples were evaluated for copper (Cu), zinc (Zn), magnesium (Mg) and iron (Fe) using flame atomic absorption spectrophotometer. There was a significant difference (P<0.001) in the mean plasma values of Cu, Zn, Mg and Fe for the three activity groups. The plasma Cu concentration was highest in the moderately active group (1.59±0.05mg/L) while the lowest in highly active group (1.06±0.12 mg/L). Physical activity caused a marked decrease in the plasma zinc concentration (Sedentary group-2.37±0.29, moderately active-1.03±0.21 and highly active -0.78±0.23mg/L). Physical activity increases levels of plasma Mg. Plasma iron levels were highest in the moderately active group (0.79±0.22mg/L) while lowest in sedentary group (0.43±0.09mg/L). Age influences plasma Cu, Zn, Mg and Fe levels in three different activity groups to different extent.