Music with an instant appeal but with little lasting significance.
There are various 'candy' phrases - ear candy, eye candy, arm candy. The one that started the whole candy franchise was ear candy. This was the title of a successful 1977 LP by Helen Reddy - no doubt in an ironic reference to the criticism she had received for producing bland, easy-listening music. The term may have been in use before 1977, although I can find no references to it in print that predate Reddy's album title. The term did get picked up though and soon became a generic term for music that was initially attractive but with little lasting substance.
Candy is of course what the US calls the confectionery that many parts of the English-speaking world calls sweets. The sugary, insubstantial imagery is well suited to these phrases.
Despite having a 1950s bubblegum image, candy is actually an old word. It is first recorded in print in the 1420 cookery book 'The Liber cure Cocorum'. The book is quite a shock to the senses for anyone familiar with modern-day cook-books. Naturally, it lacks the now obligatory colour pictures but redeems itself by being written throughout in rhyming couplets. Here's a recipe for frumente (a fermented wheat dish):
With sugur candy, you may hit dowce,
If hit be served in grete lordys howce.
[When serving frumente in a great lord's house, you may sweeten it with sugar candy]
Sugar candy was basically just sugar boiled in water until it crystallized, and that term was used for some time before candy started to be used. When first coined, candy referred to candied ginger or fruits, as here in Sir Thomas Elyot's The castel of helth, 1533 (health? - presumably Sir Thomas didn't foretell modern dental theory):
"Gynger... candyd with Sugar."
Candy was also known to Shakespeare (as caudie), who referred to it in Henry IV Part I , 1597:
"Why what a caudie deale of curtesie, This fawning Grey-hound then did proffer me."
Having taken ear candy into the language, eye candy followed soon afterwards. In March 1978 The Oakland Tribune ran a review of the TV show Three's Company, which it derided for its gratuitous, sexually titillating content:
"They call the new show 'eye candy'."
We had to wait a little longer for arm candy. This appeared in the 1990s, about no other than Marilyn Monroe. In August 1992, The Chicago Tribune's Marcia Froelke Coburn included this in a piece about the 1950 film All About Eve:
"She'd already had mini-roles in eight movies when she turned up as George Sanders' arm candy in the party scenes of this film."
See other phrases and sayings from Shakespeare.