In the commercial, people line up to inhale helium, their voices change and they float to the ceiling. Earlier this year, Saatchi & Saatchi was named lead agency for Wendy's but it was unclear whether the agency created the ad. Wendy's did not return a call for comment.
In an e-mail message, the coalition says helium displaces oxygen in the lungs, which can lead to disorientation and possible loss of consciousness.
The group asks consumers to send or fax a letter to Wendy's to express concern, contact colleagues, media and schools.
"When writing Wendy's you might mention their stated Community Commitment slogan," suggests the group, which says it is "Caring for Others: Wendy's is committed to doing what's right."
--Nina M. Lentini