The first lady will tout her drink more water campaign in an episode that will air in November, according to NBC.
Broadcasting and Cable first reported the news.
Brita, one of the sponsors on "The Biggest Loser," is a supporter of Obama's initiative.
The first lady last appeared on the show in April 2012, where she joined the contestants in a workout at the White House as part of her Let's Move anti-obesity campaign.
— This post was updated at 12:56 p.m.