Montreal and Toronto – In a bid to compare bad fat versus good fat, researchers undertook a study to compare the effects of junk food and a typical Mediterranean meal on the vascular endothelium – the inner lining of the blood vessels.
The study was lead by Dr. Anil Nigam, Director of Research at the Cardiovascular Prevention and Rehabilitation Centre (ÉPIC) and associate professor at the University of Montreal, Faculty of Medicine. The findings were that a single junk food meal, composed mainly of saturated fat, is detrimental to the health of the arteries, while no damage occurs after consuming a Mediterranean meal rich in good fats such as mono-and polyunsaturated fatty acids. The Mediterranean meal may even have a positive effect on the arteries.
The results were established in 28 non-smoking men, who ate the Mediterranean-type meal first and then the junk food-type meal one week later. Before beginning, the men underwent an ultrasound of the antecubital artery at the elbow crease after fasting for 12-hours to assess their baseline endothelial function. The researchers then tested the effects of each meal. The first was composed of salmon, almonds, and vegetables cooked in olive oil, of which 51% of total calories came from fat (mostly monounsaturated fatty acids and polyunsaturated fats.) The second meal consisted of a sandwich made of a sausage, an egg, and a slice of cheese, and three hash browns, for a total of 58% of total calories from fat: extremely rich in saturated fatty acids and containing no omega-3s. At two hours and four hours after each meal, participants underwent further ultrasounds to assess how the food had impacted their endothelial function.
Dr. Nigam and his team found that after eating the junk food meal, the arteries of the study participants dilated 24% less than they did when in the fasting state. In contrast, the arteries were found to dilate normally and maintain good blood flow after the Mediterranean-type meal. “These results will positively alter how we eat on a daily basis. Poor endothelial function is one of the most significant precursors of atherosclerosis. It is now something to think about at every meal,” Dr. Nigam said.
The findings were presented in Toronto at the Canadian Cardiovascular Congress, which ended October 31, 2012.