Olive oil supplements may protect from pollution

AIR pollution in many cities has taken a turn for the worse as a result of population increase and related factors. According to Dr Haiyan Tong, MD, PhD, a research biologist with the United States Environmental Protection Agency (EPA), exposure to airborne particulate matter causes the endothelium (inner lining of the blood vessels) to function abnormally. This condition may lead to cardiovascular problems and even atherosclerosis.

During the 2014 American Thoracic Society International Conference, held from 16-21 May in San Diego, California, Dr Tong shared a study on the neutralising effects of olive oil supplements on exposure to airborne particulates. Olive oil has always been known to be good for the heart.

“As olive oil and fish oil are known to have beneficial effects on endothelial dysfunction, we examined whether use of these supplements would counteract the adverse cardiovascular effects of exposure to concentrated ambient particulate matter in a controlled setting,” he said.

Dr Tong’s study involved 42 healthy adults who were randomised to receive either 3 gram/day of olive oil, fish oil, or no supplements for 4 weeks before undergoing controlled two-hour exposures to filtered air, followed on the next day by exposure to fine/ultrafine concentrated ambient particulate matter (CAP, mean mass concentration 253±16 μg/m3) in a controlled-exposure chamber.

Endothelial function was assessed by sonographic measurement of flow-mediated dilation of the brachial artery before, immediately after, and 20 hours after exposure to air and CAP. Blood markers of vasoconstriction and fibrinolysis (a body process that keeps blood clots from growing) were also measured.

Immediately after exposure to CAP, significant particulate matter mass-dependent reductions in flow-mediated dilation were observed in the control (-19.4±8.4% per 100 μg/m3 increase in CAP concentration relative to pre-filtered air levels) and fish oil groups (-13.7±5.3%); the decrease in the olive oil group was not significant (-7.6±6.8%).

Tissue plasminogen activator, a protein involved in the breakdown of blood clots, increased (11.6±5%) immediately after CAP 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. Fish oil supplementation had no effect on endothelial function or fibrinolysis after CAP exposure.

“Our study suggests that use of olive oil supplements may protect against the adverse vascular effects of exposure to air pollution particles,” said Dr Tong. “If these results are replicated in further studies, use of these supplements might offer a safe, low cost, and effective means of counteracting some of the health consequences of exposure to air pollution.”