The Panorama investigation found evidence of multiple takeaways providing false and potentially life threatening allergen information.
Tong Feng House in Greater Manchester assured an undercover reporter on the phone that its chicken chow mein did not contain wheat, yet it was found to have a high wheat content.
Similarly, Mama Mia Pizza in Birmingham sold a burger that it said did not contain wheat yet was found to contain gluten.
Another restaurant, Karo’s Pizza in Liverpool, was unable to answer a direct question about whether its cheese burger would be safe to eat by someone with a wheat allergy.
Just Eat, the biggest online food delivery app in the UK, does not require restaurants to provide allergen information on its app or website.
The company told Panorama it was “concerned to learn about the individual restaurants not providing accurate information.”
“We launched an immediate investigation and have already offered further support and training,” it said.
Karo’s Pizza and Mama Mia Pizza said staff did not understand the questions they were asked and both said they display allergy information in store.
Tong Feng House told the programme, broadcast on BBC1 tonight, that a new staff member provided the incorrect information and they are retraining their team.
The investigation also found the Just Eat app listed more than 100 takeaways with zero hygiene ratings.