One of the main characteristics of the Mediterranean diet is the frequency of vegetable-rich meals and salads cooked in plenty of olive oil. And while we know that the addition of olive oil to vegetables can increase the absorption of vitamins and antioxidants, it appears that this powerful combination has another significant health effect: it may protect from high blood pressure.
A new study published in the journal PNAS, suggests that an eating pattern that combines unsaturated fats (such as olive oil) with specific vegetables rich in in nitrite and nitrates can protect from hypertension. Nitrite rich vegetables are mainly green leafy types such as spinach, wild greens, and root vegetables. These vegetables are consumed on a daily basis within a Mediterranean diet and always with olive oil. Researchers found that when these two foods are combined you have the formation of nitro fatty acids.
For this study, mice were used to examine how nitro fatty acids control blood pressure by inhibiting an enzyme that is known to regulate blood pressure.
The results showed that the mice genetically engineered not to be reactive to this enzyme process had no change in blood pressure, while in normal mice the nitro fatty acids lowered the blood pressure.
The researchers concluded that the common combination of unsaturated fatty acids such as olive oil with these vegetables contributes to the protective action of the Mediterranean diet.
In another study published in the journal PLOS ONE, researchers were able to demonstrate by using mass spectrometry, that extra virgin olive oil as well as fresh olives are also a source of nitro fatty acids on their own, thus potentially contributing even more to the antihypertensive effect.