Twitter has faced questions from the advertising watchdog after a marketing campaign for Snickers.
The regulator was called in when complainants claimed that the posts sent from the official accounts of footballer Rio Ferdinand and model Katie Price could be clearly identified as adverts.
This is the first investigation involving Twitter.
The Advertising Standards Authority (ASA) dismissed the objections and ruled the two series of tweets did not breach industry codes.
The posts - which both related to Snickers - were all put on Twitter within an hour in January of this year.
Both series started with several "out of character" posts, with Ferdinand claiming to have a found a new love of knitting and Price commenting on international economic policy. The final tweet carried a picture of each star with a Snickers bar and claimed that, "you're not yourself when you're hungry."
The final tweet also contained "#spon" and a link to the Snickers Twitter feed to indicate that they were adverts.
Former glamour model Katie Price (aka Jordan) said:
And former Manchester United and England defender Ferdinand Tweeted:
The ASA said: