In a small Italian study, researchers assigned 25 healthy adults to a Mediterranean meal (pasta, chicken breast, salad, bread, and an apple) prepared either with or without olive oil, then measured their cholesterol and blood sugar. After 30 days, the participants switched groups and ate the other meal, serving as their own control. The scientists found that 2 hours after eating, the meal without olive oil was associated with higher glucose and insulin levels, as well as higher “bad cholesterol” (LDL-C). In the second part of the experiment, the participants were assigned to a Mediterranean meal prepared with either olive oil or corn oil, switching groups after a 30 day washout period. Their blood sugar and cholesterol was tested after the meals as well. Two hours after eating, the meals with olive oil were associated with a lower increase in blood sugar and improved markers of blood sugar control (such as lower DPP, and higher GLP1 & GIP), as well as a smaller increase in “bad cholesterol” (LDL-C and oxidized LDL). These experiments indicate that meals with olive oil can help regulate blood sugar, and may help improve cholesterol.
Nutrition & Diabetes. 2015 July 20;5:e172. [Epub ahead of print.] (Violi F et al.)