Effect of consumption of fresh and heated virgin coconut oil on the blood pressure and inflammatory biomarkers: An experimental study in Sprague Dawley rats

Background: It is a common practice to heat cooking oil and reuse it in order to cut expenses. The use of repeatedly heated cooking oil predisposes to various cardiovascular diseases. Virgin coconut oil (VCO) is reported to possess antioxidant action. Aim: The study aimed to determine the effect of heating of VCO on the blood pressure (BP) and inflammatory bio-markers. Methods: Thirty male Sprague-Dawley rats were divided into five groups and were fed with the following diet for 24 weeks: normal rat chow (control); chow + fresh VCO (FVCO); chow + VCO heated once (1HVCO); chow + VCO heated five times (5HVCO) and chow + VCO heated ten times (10HVCO). BP was measured at baseline and four weekly for 24 weeks. Blood was collected at baseline and at the end of study to measure plasma TXB2, PGI2, VCAM-1, ICAM-1 and LDH enzyme activity. Results: BP increased significantly in the 5HVCO and 10HVCO groups compared to the control and FVCO groups. The 5HVCO and 10HVCO diet caused a significant increase in the plasma TXB2 and a significant decrease in the plasma PGI2 level. The plasma levels of VCAM-1, ICAM-1 and CRP were significantly increased in the 10HVCO group. Conclusion: Repeatedly heated VCO caused an elevation in the BP. The BP elevation was associated with a significant increase in the inflammatory bio-markers (VCAM-1, ICAM-1 and CRP), TXB2 and a significant reduction in the plasma PGI2 level.