Olive Oil May Counter Cardiac Effects of Air Pollution

Rich in monounsaturated fatty acids, olive oil is a staple of the Mediterranean diet – with which a number of cardiovascular benefits are associated. Haiyan Tong, from the US Environmental Protection Agency (North Carolina, USA), and colleagues enrolled 42 healthy adults in a month-long study in which each received either 3 gram/day of olive oil, fish oil, or no supplements for 4 weeks before undergoing controlled 2-hour exposures to filtered air, followed on the next day by exposure to fine/ultrafine concentrated ambient particulate matter in a controlled-exposure chamber.  The team assessed endothelial function by sonographic measurement of flow-mediated dilation of the brachial artery before, immediately after, and 20 hours after exposure to air and the concentrated particulate matter.  They also measure blood markers of vasoconstriction and fibrinolysis.  Immediately after exposure to the concentrated particulate matter air, significant particulate matter mass-dependent reductions in flow-mediated dilation were observed in the control and fish oil groups, while the decrease in the olive oil group was not significant.  Further, tissue plasminogen activator, a protein involved in the breakdown of blood clots, increased immediately after concentrated particulate matter air exposure in the olive oil group, and this effect persisted up to 20 hours. Olive oil supplementation also ameliorated changes in blood markers associated with vasoconstriction and fibrinolysis, while fish oil supplementation had no effect on endothelial function or fibrinolysis after exposure to concentrated particulate matter air.  The study authors submit that: “These data suggest that [olive oil] supplementation may offer protection against the adverse vascular effects of exposure to air pollution particles.”