Changes in Serum Lipid Profile and Malondialdehyde following Consumption of Fresh or Heated Red Palm Oil

The effect of chronic consumption of fresh and heated red palm oil (RO) on lipid profile and lipid peroxidation was investigated. Thirty male rats were divided into 3 groups, each treated with the following prescribed food: (i) basal diet fortified with 15% weight/weight (w/w) fresh red palm oil (FRO), or (ii) heated once red palm oil (1H-RO) or (iii) heated 5 times red palm oil (5H-RO) for 20 weeks. There was a significant increase (p<0.05) in MDA concentration in all 3 groups compared to their respective baseline concentrations and a significant decrease (p<0.05) in total cholesterol (TC) concentration. However, the transient changes observed in serum triglyceride and HDL-cholesterol concentration did not attain significant values.
The LDL-cholesterol concentration in 5H-RO group increased significantly (p<0.05) compared to pretreatment value, FRO and 1H-RO groups. Ratio of TC/HDL in 5H-RO group initially increased, but dropped to baseline level at the end of the study. There was no significant difference in the ratio of TC/HDL between the groups.
In conclusion, both fresh and heated RO appeared comparable in their effect on serum cholesterol and lipid peroxidation. It appears that long term feeding with fresh and heated RO did not have an adverse effect on serum TG, HDL and TC/HDL ratio. However, it appears that prolonged heating increases LDL-cholesterol level. Further studies are required to ascertain whether the increase in LDLcholesterol and MDA with heated oil would render it more atherogenic.