From Muppet Wiki

The Ad Council is a non-profit agency which since 1952, has been the leading producer of television public service announcements, often "sponsored" by specific non-profit groups and government agencies. Ad Council spots typically address such issues as public safety, personal health, and wider issues such as adoption. Their best known creations include Smokey Bear and McGruff, the dog who "takes a bit out of crime." Various advertising agencies over the years have donated their services in creating the campaign.

Over the years, many Ad Council campaigns have involved the participation of celebrities. In 1974, their "Nutrition Campaign" featured Cookie Monster, in both 30 second and 60 second versions of the same spot. The spot was scripted by Norman Stiles, with input from Louis DiJacobs of Young, Rubican and Associates.

Decades before the Cookie Is a Sometime Food controversy, Cookie Monster encourages healthy eating habits. To the astonishment of a roving reporter (off-screen voice-over), Cookie Monster explains that even he can't eat only cookies and expect to be healthy. He proceeds to dine on meat and fish, carrots and peas, fruits, and then milk. For dessert, Cookie Monster brings out a whistle, summoning a truck load of cookies.

The commercial is available for viewing at The Museum of Television and Radio.