Pictures of the event showed him chewing gum and then removing it while Prime Minister Narendra Modi was talking to him.
Though there was a lot of commentary on social media on his chewing gum at a formal ceremony, this was not the first time Obama has been spotted doing so.
Comments on twitter included remarks by famous author Shobha De, who said, "Barack bhai working his jaws overtime and chewing gum! At least it isn't gutka. But seriously - gum during a formal parade?".
American media in past has commented about Obama's habit of chewing gum while referring to his medical report, according to which the US President was in excellent health except for a minor problem of "history of smoking".
But Obama was now "tobacco free" buoyed by the "occasional use" of "Nicotine Gum", said a report in Washington Post.