We all know the high levels of fat, sugar and salt often present in fast food means it isn't great for our health.
But a new study also raises concerns over the impact fast food packaging may have on our bodies.
The study, led by researchers at the George Washington University, found that people who eat higher levels of fast food are exposed to higher levels of potentially harmful chemicals known as phthalates.
Phthalates belong to a class of industrial chemicals used to make food packaging materials, tubing for dairy products, and other items used in the production of fast food.
Previous research suggests these chemicals can leak out of plastic food packaging and can contaminate highly processed food.
The researchers looked at data on more than 8,000 participants who had answered detailed questions about their diet in the past 24 hours, including consumption of fast food.
These participants also provided the researchers with a urinary sample that could be tested for the breakdown products of two specific phthalates: DEHP and DiNP.
The team found that the more fast food participants in the study ate the higher the exposure to phthalates.
People in the study with the highest consumption of fast food had 23.8% higher levels of the breakdown product for DEHP in their urine sample.
Those same fast food lovers had nearly 40% higher levels of DiNP metabolites in their urine compared to people who reported no fast food in the 24 hours prior to the testing.
"People who ate the most fast food had phthalate levels that were as much as 40% higher," lead author Ami Zota commented.
"Our findings raise concerns because phthalates have been linked to a number of serious health problems in children and adults."
The researchers also discovered that grain and meat items were the most significant contributors to phthalate exposure.
Zota said the grain category contained a wide variety of items including bread, cake, pizza, burritos, rice dishes and noodles.
A spokesperson from the Foodservice Packaging Association said its members "adhere to a strict code requiring that all the packaging they place on the market is proven to be safe in conjunction with food and drink".
"For a number of years we have asked the Food Standards Agency to clamp down on imports of packaging into the EU which does not carry such approved certification, " they told The Metro.
"A large quantity of packaging arrives in the UK and documentation is not always checked at customs.
"We urge the Government to take further action on this ‘illegal’ packaging and to ensure the health of the public is given greater priority."
For anyone concerned about phthalates, Zota pointed out that cutting down on the amount of fast food you eat won't do your body any harm.
"People concerned about this issue can't go wrong by eating more fruits and vegetables and less fast food," she said.
"A diet filled with whole foods offers a variety of health benefits that go far beyond the question of phthalates."
The study appears in full in the journal Environmental Health Perspectives.