Background: Repeated heating of vegetable oils especially palm oil that is commonly and commercially used in frying of food at homes and restaurants has been investigated for its risks on health status. It seemed to carry potential hazards on the liver tissue.
Aim: To investigate the impact of eating foods fried with 5-times heated palm oil on liver of adult male rats for 8 weeks and the possibility of recovery of histomorphometric changes after stoppage of use of reheated palm oil for additional 4 weeks.
Material and Methods: Thirty adult male albino rats were divided equally into 3 groups; control group (received normal balanced diet for 8 weeks), H5 group (received 5-times heated palm oil enriched diet for 8 weeks) and Recovery group (received five times heated palm oils for 8 weeks and then left on balanced diet for another 4 weeks). At the end of the experiment, animals were anesthetized with ether then sacrificed. Specimens taken from the liver were processed for histological evaluation. Morphometric studies were conducted and collected data undergone statistical analysis.
Results: Histological examination showed alterations in liver tissue of H5 group including fat droplets, mononuclear cellular infiltration, dilatation of central vein and blood sinusoids, collagen deposition and degeneration and necrosis of hepatocytes. Ultrastructural examination showed lipid droplets, irregular mitochondria, cytoplasmic vacuolation, irregular nuclear envelop and dilatation of endoplasmic reticulum. Recovery group showed decreased lipid droplets, less dilatation and congestion of central vein and blood sinusoids, decreased inflammatory cells but few hepatocytes still show degeneration. Ultrastructure of hepatocytes of recovery group became more or less normal with restoration of cytoplasmic organelles. Morphometric results support the histological findings.
Conclusion: Consumption of repeatedly heated palm oil is injurious to the liver tissue, and those injuries show possible recovery after stoppage of its consumption.