It certainly was, although capping sun exposure to pre cancer levels was the message:

    One of the most successful health campaigns in Australia's history was launched in 1981, when a cheerful seagull in board shorts, t-shirt and hat danced his way across our TV screens singing the jingle. 

    'Slip, Slop, Slap!
    It sounds like a breeze when you say it like that
    Slip, Slop, Slap!
    In the sun we always say 'Slip, Slop, Slap!' 

https://www.youtube.com/watch?v=b7nocIenCYg

and then there was the Life, Be in It campaign (1975) promoting exercise and good diet, eg:

https://www.youtube.com/watch?v=GNjEge3Awl8 https://www.youtube.com/watch?v=uuqDlF8DUuY