COPPER UTILIZATION IN LOW-FAT DIETS

The objective of this study was to investigate both the dietary copper utilization and the body copper content in rats fed either low fat di ets (2%) or normal fat diets (8%) containing olive oil, sunflower oil and palm oil (olein fraction), by two different balance techniques. Se ven groups of Wistar rats were used. One group was killed on the first experimental day, being utilized as control of initial body copper co ntent. Six groups of rats were fed, over 15 days, semipurified diets v arying only in the fat level, three of them containing 8% of fat, and the other three 2%. The overall copper balance was studied by calculat ing differences between the initial and final body copper content. Dur ing the last week, another copper balance was carried out by monitorin g intake and faecal copper excretion. Body mass, and liver, spleen, sk in, erythrocytes and serum copper contents were also examined.The copp er utilization was lower in 2% fat rats, this was caused by food intak e decrease but also by the lower copper bioavailability in 2% fat diet s. The corporal, liver and spleen copper contents were reduced, and li ver, skin and serum copper concentrations also decreased in the rats f ed on 2% fat diets. Palm olein (8%) versus olive and sunflower oil pro duced a lower efficiency of copper absorption.