A leading music expert has developed the world’s happiest Christmas car playlist, said to be ‘guaranteed’ to keep everyone smiling. Dr. Claire Renfrew, a music psychologist, sifted through hours of festive tracks to find the perfect songs, with each one adhering to a scientific formula.

The tune that scientifically hits all the right notes is Brenda Lee’s ‘Rockin’ Around the Christmas Tree’—although a survey of 2,000 motorists who celebrate Christmas found that Mariah Carey’s ‘All I Want for Christmas Is You’ (45%) is the track that makes them happiest.

Other songs that fit the formula include ‘Feliz Navidad’ by José Feliciano, ‘Jingle Bell Rock’ by Bobby Helms, and ‘Holly Jolly Christmas’ by Michael Bublé, along with classics like ‘I Wish It Could Be Christmas Everyday’ by Wizzard.

As a result, Dr. Renfrew has created the ‘World’s Happiest Christmas Car Playlist by Fiat’. The 25-track playlist is designed to bring joy to drivers during the holidays and help combat the stress of traveling.

The playlist, available for free on Spotify, is ranked in order of how closely each song fits the scientific formula.

Dr. Renfrew said: “Christmas songs can have a surprisingly powerful positive impact on us psychologically. Not only do Christmas songs boost our moods, they reduce stress, evoke nostalgia, enhance social bonding, and increase energy.”

She added that they also “trigger joyful anticipation and improve emotional regulation, making them powerful psychological tools for happiness and festive well-being.”

The poll, conducted via OnePoll.com, found that 54% of those driving home for Christmas consider it one of the best moments of the season. Yet, despite it being a highlight, 47% believe it’s the most stressful time to be on the roads.

More than one in ten (13%) said they will be on the road for longer than an hour, with most travelling by car with their partner and children. To help keep children entertained on the journey, 76% said they will listen to Christmas songs.

Victoria Hatfield of FIAT UK, which commissioned the research following the launch of its Grande Panda in the UK, said: “Happiness is part of our brand ethos and we believe that driving home for Christmas doesn’t need to be stressful, but should be celebrated as the start of the festive period”

“By getting the right playlist and plans in place, you can have a magical and stress-free drive home ahead of the big day.”

So, what’s the secret recipe for a dopamine-boosting Christmas song? According to Dr. Renfrew’s formula, the happiest festive tunes have a few things in common:

• They’re in a major key (think bright and cheerful!)

• Feature energetic vocals and instruments

• Have a tempo between 100 and 140 beats per minute

• Include a simple, catchy chorus

• And often follow a classic structure: Verse > Chorus > Verse > Chorus > Instrumental > Chorus