You'll Never Guess Why The NFL Banned This Super Bowl AdThe ad contains substances which are banned by the football league.

Vitamin retailer GNC's Super Bowl ad was rejected by the NFL, despite this year's big game broadcaster initially approving it,AdAge reported.

GNC's marketing boss, Jeff Hennion, toldAdAgethe ad was rejected because some of the retailer's products contain substances that are banned by the football league. However, Hennion said fewer than 3 percent of its products contain ingredients that are included in the NFL's banned substances list.

Hennion said he only received notice of the ad ban on Jan. 30, a mere six days before Super Bowl LI takes place between the Patriots and the Falcons at the NRG Stadium in Texas.

Fox had cleared the ad for broadcast, although it had asked GNC to tone down its logo -- which contained the brand name within a pill bottle -- according to Hennion. GNC complied with the request, but now the ad has been rejected altogether because NFL has final approval rights over Super Bowl commercials.

Hennion toldAdAge: "So many people invested so much. We are extremely disappointed for all the people involved."

Fox, GNC and the NFL did not immediately returnBusiness Insider's requests for comment.

GNC was hoping to use its Super Bowl spot as the tentpole moment for a big rebranding campaign

The company posted a set of three teaser videos online, under the banner "Courage To Change," on Jan. 25:

Hennion toldAdAgeits big game TV spot will still go ahead and air later on -- just not during the Super Bowl.

GNC is not the first brand to have its Super Bowl creative barred this year.Construction-supply company 84 Lumber had to go back to the drawing board after its first ad was rejected by Foxfor being too political. The creative had featured a wall blocking people looking for work in the U.S.