Love languages are hugely popular – but there’s very little evidence they exist at all

The concept is said to increase relationship happiness, but research provides few words of affirmation for its effectiveness

Love languages - the concept coined by Baptist pastor Gary Chapman some 30 years ago - has taken the relationships world by storm. It's often the go-to" topic on first dates, and for those in relationships love languages are said to provide deep, meaningful and reliable insights into how relationships function. Putting love languages into action is believed to increase relationship happiness.

The concept clearly has appeal. At last count, 20m copies have been sold worldwide of Chapman's 1992 book The Five Love Languages: The Secret to Love that Lasts. The book has been translated into 49 languages.