It's not the jingle the company may have been looking for, but a fast food chain known for its healthy fare may be serving up a fitness-related element its customers never intended to eat.

Subway is announcing that it will remove a chemical that is used in shoe soles and yoga mats from its dough. The chemical, azodicardonamide, helps produce air within the foam of things like athletic equipment and, as it turns out, bread.

The use of the fluff-making fodder was uncovered by Food Babe bloggist Vani Hari, whose petition designed to get Subway to discontinue use of the additive received tens of thousands of signatures. Despite the fact that azodicardonamide is banned throughout Europe and Australia, it is still legal in the United States.

Company officials have responded by saying that, even before Hari's petition, they were already planning to remove the chemical.

This is the latest issue to be facing the sandwich chain.   Subway has come under fire from critics after they recently announced partnership with First Lady Michelle Obama.  She has signed on to help push healthy eating for children with Subway's help. They will spend $41 million dollars over the next few years on the healthy eating campaign.

After the National School Lunch debacle in 2012-13,  some say the chain might want to steer clear of her involvement.  The First Lady spearheaded the USDA school lunch menu initiative that drastically changed food choices at thousands of schools across the country, with poor results.   It's estimated hundreds of millions of dollars worth of food was wasted because, simply, the students couldn't stand the taste of the foods offered - which in some cases included hummis!