Published March 29, 2013
Olive oil is essential to the Mediterranean diet, known for its antioxidants and oleic acid, which has heart-protective qualities.
But, some new research suggests the smell of olive oil could be adding to those health benefits, the New York Times reported.
Compared to other oils and fats, extra virgin olive oil is more likely to make a person feel full and satisfied – but the study also showed that by just exposing an aromatic extract of olive oil to food improved persons’ blood sugar response and had them eating less calories.
“We wanted to see whether there was a way to reduce the fat content of food without losing its taste or aroma,” Dr. Malte Rubach, a nutritional scientist who, along with colleagues at the German Research for Food Chemistry, aided in the government-funded, institute-based study, told the Times.
Researchers did not receive any funding from olive oil manufacturers, it was noted; and they started by looking at the outcomes of four different fats (lard, butter, olive oil and canola oil) on feelings of satiety, the Times said.
The researchers spilt 120 people into five groups, and everyone was told to eat 500 grams of yogurt every single day for three months. The yogurt was enhanced with one of the four fats in four groups; the fifth group ate plain yogurt with no fat.
No one knew what type of yogurt they were eating, only that it could be enriched with an animal or plant-based fat, Rubach told the Times. The subjects were routinely given blood tests – and the group that ate the yogurt with olive oil showed increases in serotonin, which is a hormone correlated with satiety.
On many days, the olive oil group ate less calories, so they did not gain weight, similar to the butter and control groups.
Incidentally, the canola and lard groups gained weight during those three months.
Rubach noted it was obvious those latter groups did not feel satiated, despite the similarities between canola and olive oil when it comes to health benefits.
So the next phase looked at whether there was something else besides the oils’ nutrients that justified the weight differences.
Now, the subjects were parted into two groups, each given zero-fat yogurt – however, in one group, the yogurt was infused with an extract imparting the aroma of olive oil.
The serotonin levels dropped in those people who ate plain yogurt; they also said they felt less satiated after eating it. They ate an average of 176 calories more a day.
Interestingly, the group who ate the flavored yogurt, reduced their caloric intake and blood work showed better blood sugar control.
Rubach told the Times the study was too small to draw “any general recommendations,” but consumers should recognize the psychological impacts of the study – your meal is not limited to what you see on your plate.