When it comes to fast-food chains, we've all undoubtedly had a moment or two where we've wondered what exactly we were eating.
But one woman has told how she's now sworn off the stuff for good after finding a McDonald's cheeseburger she'd kept for five years.
Receptionist Megan Condry claims she purchased two cheeseburgers and some fries from a McDonald's drive-thru back in November 2017 - but after finishing off one burger, she threw the other in the back of her car and planned to eat it later.
The 41-year-old from Washington DC, forgot about the burger for a few days and when she found it later noticed it hadn't started to go bad, so she decided to conduct an 'experiment' to see how long it would stay that way.
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Megan stored the burger in the back of her wardrobe for five years and discovered it again last month while sorting out her Christmas decorations - and she was flabbergasted by the results.
Despite it being 'rock hard' Megan said it still looks the same as the day she bought it.
The bun, beef patty and cheese remain intact with no sign of mould or rot having taken hold.
McDonald's said that they only use 100% USDA inspected beef and that there are 'no preservatives or fillers' in their beef patties.
Megan said: "It was untouched until around three weeks ago.
"I was in the closet sorting my Christmas stuff and I knocked the bag and the burger rolled out. I'd forgotten about it.
"It was rock hard, as hard as a hockey puck. I could probably smash a window with it. Everything is completely dry and it could start to crumble.
"There was no smell whatsoever and it looks the same as the day I bought it.
"I've tried to pry it apart but if I try to take it apart, I think it would break. It's just a solid mass.
"I want to know what it looks like on the inside but I can't see it.
"It hasn't shrunk in size or evaporated. I assume there's no bacteria to it, it makes me sick.
"I think it has so many preservatives [in it] or how else would it have lasted that long?"
Megan went on to say she was inspired to carry out the experiment after seeing an old burger being showcased in her doctor's office.
After finding the burger in the back of her car five days after she bought it, the receptionist scribbled the date on the bag and kept it hidden away.
Megan said: "I like science stuff. A couple of years before I went to the doctor and he had a cake stand with a burger displayed that he'd kept for 20 years.
"I would have just thrown it out if it wasn't for me seeing the burger in the doctor's office.
"I threw it in the back of my closet and left it untouched until a few weeks ago."
After seeing the results of her experiment, Megan has vowed never to eat McDonald's again and has even ditched fast food altogether in a bid to lose weight.
And as well as quitting fast-food, Megan has planned to continue on with her experiment - putting the burger back in the cupboard for another five years.
She added: "I'm going to put it back in the closet and see if it dies or changes or disappears.
"McDonald's isn't my thing, I got it that day because it was close to work but I have friends who eat fast food on a regular basis and they say they feel sick.
"People think it's so gross. It doesn't surprise me that it didn't rot. Is this why we feel bad after eating fast food?
"Whenever I ate it, my stomach wouldn't feel good. I can't imagine wrapping my hand around that and eating it now."
A spokesperson for McDonald's USA commented: "Our burgers are made only with 100% USDA inspected beef. There are no preservatives or fillers in our patties and the only thing ever added is a touch of salt and pepper on the grill."
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