Need a pick-me-up? Just have a spoonful of some vanilla yogurt.
Scientists have long suspected that the bacteria found in fermented foods, such as yogurt, can boost your mood.
A new study, however, recently published in the October edition of the journal Food Research International, suggests yet another reason why yogurt can make us happy.
It turns out that sometimes yogurt may be more tasty than we tend to expect -- and so when we're pleasantly surprised by its deliciousness, that surprise factor can put a smile on our face -- and the vanilla flavor may be comforting.
"Eating food is often reducing unpleasant feelings of dissatisfaction and is thus often used to improve mood," Dr. Jozina Mojet, a scientist at the Food & Biobased Research Institute in the Netherlands and lead author of the study, told The Huffington Post in an email.
For the study, three groups of at least 24 men and women were given a pair of yogurts of the same brand that were marketed in the same way, but had different flavors and fat content.
Next, the researchers tracked the participants' eyes, examined their facial expressions and asked them to record whether they liked or disliked the yogurt. The participants also completed an emotive projection test, which is used to measure emotions.
The participants were shown photos of people and were asked to rate the people based on six positive and six negative personality traits -- whatever positive or negative traits a participant projects onto the photos allows the researchers to gauge whether the participant's own mood is positive or negative.
The researchers found that eating the vanilla yogurt resulted in the participants projecting more positive emotions than when they ate the other flavors, and that yogurts with lower fat content gave people a stronger positive emotional response. This was even true when the participants had said that they did not like the yogurt, or weren't familiar with the brand.
"We were surprised to find no clear relationship between liking [the yogurt] and the mood effects, since a positive relationship is generally assumed," Mojet said.
But why vanilla? Maybe participants weren't sure how a neutral-colored yogurt would taste due to their past experiences with varieties of flavors, and then were pleasantly surprised.
There's also the possibility that the vanilla flavor itself may have played a role. Previous studies have shown that the scent of vanilla can reduce aggression and promote relaxation.
Celebrity nutritionist Shira Lenchewski told Yahoo Health that she was not entirely surprised by the study results, especially since vanilla can be a mood-booster.
"Certain scents can boost your mood via endorphins -- the brain’s feel-good chemicals -- and vanilla happens to be a strong aromatic stimulant, shown to help reduce anxiety," she said.
Mojet also pointed out that our positive associations with vanilla may go back to when were babies.
"Volatile compounds, such as vanilla, are transferred from the mother's diet to her milk," she said. "This makes people, from their birth on, learn to like vanilla by mere exposure. This memory trace is very comforting."
The researchers concluded that, by focusing on emotion and associations, their study has offered a new way to measure exactly how people may subconsciously respond to food.
Also on HuffPost Science: