Inspired by the movie Super Size Me, genetics professor Tim Spector decided to bring the excessive fast food consumption experiment a little closer to home: by having his college-aged son, Tom, eat McDonald’s for every single meal 10 days in a row.The purpose? To discover just how extreme the effects of a greasy fast food diet are on our gut bacteria (the tiny, vital microbial organisms in our intestines that help us digest and fight off bad bacteria). Don’t worry: Tom, a genetics student at a top Welsh university, wasn’t force-fed Big Macs; he actually thought of the experiment himself in conjunction with his father’s experiments with various eating habits to expel “the diet myth.”
The results of the experiment were horrific, but not too surprising. As Tom told his father, “I felt good for three days, then slowly went downhill, I became more lethargic, and by a week my friends thought I had gone a strange grey color. The last few days were a real struggle. I felt really unwell, but definitely had no addictive withdrawal symptoms.” Test results confirmed that Tom’s gut bacteria count had been devastated: “After just a few days Tom had lost an estimated 1,400 species — nearly 40 percent of his total. The changes persisted and even two weeks after the diet his microbes had not recovered.”
Father and son wrote about their experience in a Quartz guest column, confirming that the tiny, imperative bacteria in our digestive tracts desperately need a varied diet to survive — and, more importantly, to help us survive.