Whether rich or poor, one thing unites Americans of all economic classes: Our love for fast food.
A new nationwide study of young baby boomers contradicts the popular belief that fast-food consumption is concentrated among the poor.
Results showed that middle-income Americans were most likely to eat fast food, although the differences from other groups was relatively small. Even the richest people were only slightly less likely to report fast food consumption than others.
"It's not mostly poor people eating fast food in America," said Jay Zagorsky, co-author of the study and research scientist at The Ohio State University's Center for Human Resource Research.
"Rich people may have more eating options, but that's not stopping them from going to places like McDonald's or KFC."
Zagorsky, who also has an appointment with the Ohio Education Research Center, conducted the study with Patricia Smith of the University of Michigan-Dearborn. Their study was recently published online and will appear in the November 2017 issue of the journal Economics and Human Biology.
The researchers used data from the National Longitudinal Survey of Youth, which has questioned the same group of randomly selected Americans since 1979. The NLSY is conducted by Ohio State's Center for Human Resource Research.
In the study, Zagorsky and Smith used data from about 8,000 people who were asked about their fast-food consumption in the 2008, 2010 and 2012 surveys. Participants, who were in their 40s and 50s at the time of the surveys, were asked how many times in the past seven days they had eaten "food from a fast-food restaurant such as McDonald's, Kentucky Fried Chicken, Pizza Hut or Taco Bell."
Results were compared with the participants' answers to questions about their wealth and income. While there were some slight differences in how wealth and income were related to fast-food consumption, Zagorsky said the results were similar.
Overall, 79 percent of respondents ate fast food at least once and 23 percent ate three or more meals during any one of the weeks recorded in the study.
In one analysis, the researchers divided the participants into 10 groups based on income. About 80 percent of those in the lowest 10 percent of income ate at least once at a fast-food restaurant, compared to about 85 percent of those who were ranked near the middle (40 to 50 percent) in terms of income. Of the richest 10 percent, about 75 percent reported eating at least one fast-food meal.
The number of fast-food meals eaten during the three weeks of the study showed a similar pattern. The lowest 10 percent in terms of income ate about 3.6 fast-food meals during the three weeks of the survey, compared to about 4.2 meals for middle-income people and three meals for the richest 10 percent of participants.
Another key finding was that people whose income or wealth changed dramatically during the four years of the study – either going way up or way down – didn't change their eating habits.
"If you became richer or poorer, it didn't change how much fast food you ate," Zagorsky said.
One hallmark of the heavy users of fast food was a lack of time.
The study found that fast-food eaters tended to have less leisure time because they were more likely to work and work more hours than non-fast-food eaters.
The researchers also found an interesting tidbit that should be of interest to people who saw the 2004 documentary Supersize Me. In the movie, Morgan Spurlock documented what happened to his body when he ate nothing but McDonald's for 30 days.
"I thought that was just a publicity stunt, but we found real people out there who seem to eat all their meals at fast-food restaurants," Zagorsky said.
In 2008, 10 respondents claimed to eat three times a day at fast-food restaurants, as did five people in 2010 and two in 2012.
Given that about 8,000 people participated in the survey, that suggests there may be quite a few people in the United States who go through periods of time during which they eat only fast food, Zagorsky said.
Zagorsky cautioned that there are some limitations to the study. For one, the participants were not asked what they ate at the fast-food restaurants. Some may choose healthier options such as salads, or they may sometimes just go for a cup of coffee.
Also, this study included only people in their 40s or 50s. Consumption habits may be different for people at different ages.
Zagorsky said he hopes the results of this study can help guide policymakers when they come up with laws regarding how to prevent obesity or guide nutritional choices for Americans.
"If government wants to get involved in regulating nutrition and food choices, it should be based on facts. This study helps reject the myth that poor people eat more fast food than others and may need special protection," he said.