Harvard researcher Sarah Coseo Markt and her colleagues were dining on steamed asparagus with Hollandaise sauce at a Swedish scientific meeting when they came across a critical research question. Asparagus, as you might know, has a reputation for imparting a sharp, sulfuric smell to people's urine shortly after they eat it. Later that evening, Markt and her supervisor, Harvard University epidemiologist Lorelei Mucci, experienced that truism firsthand. But surprisingly, several of their companions said they had experienced no unusual bathroom odor. Why not?
After returning to Boston, the pair decided to investigate the conundrum further. Luckily for them, they had access to surveys collected every two years by Harvard from thousands of men and women of European-American backgrounds. For the 2010 surveys, Markt and her colleagues added a question asking people to rate the following sentence: "After eating asparagus, you notice a strong characteristic odor in your urine." Roughly 60 percent of the nearly 7,000 men and women surveyed said they had “asparagus pee anosmia,” or the lack of ability to smell asparagus-influenced urine.
The diligent researchers then pinpointed the specific cluster of genes that controlled this ability, by comparing the genomes of the people surveyed to whether or not they were able to smell the asparagus-y urine. They found that a difference in 871 nucleotides—the letters that make up a DNA strand—on Chromosome 1 appeared to control whether or not one could “enjoy” the smell after a meal of asparagus.
Markt’s research, cheerfully titled "Sniffing out significant 'Pee Values': genome-wide association study of asparagus anosmia," ended up in this week’s issue of The British Medical Journal (BMJ), becoming part of a hallowed end-of-year tradition. For this "Christmas issue," the pages of the normally staid, 176-year-old publication fill with articles that might lead one to cock their head in confusion or even laugh out loud. A few past Smithsonian.com favorites include: an analysis of the heridity of magic among the characters of Harry Potter, a description of the possible circulation within Rudolph's famed nose, and "Sex, aggression and humour: responses to unicycling."
While these types of humorous studies provide a good laugh for the holiday season—and a welcome break from the typically no-nonsense journal-ese—they have also received criticism. A study published last year in Science and Engineering Ethics, for example, questioned the "ethics of ironic science." It focused on a completely tongue-in-cheek “study” in the 2001 Christmas issue of BMJ that looked at whether praying for people with a blood infection years after they were in the hospital for it had any effect on how long their hospitalization had been. The “study” “found” that even prayer four to 10 years after an illness appeared to have led to a shorter hospital stay and fever duration.
While the papery was clearly meant to be a joke, it had unexpected repercussions in the literature: Eight years after its publication, the Christmas issue study was cited unironically in a study collecting research on the effects of intercessory prayer.
"Publishing ironic science in a research journal can lead to the same troubles posed by retracted research," the authors of last year's analysis concluded—namely, that these studies can get put into research databases without any context that would indicate their irony. For this reason, the authors suggest filing these satirical studies separately from regular research. (BMJ editor Navjoyt Ladher says that the journal remains "mindful" of any potential misinterpretation by marking all of its Christmas issue articles in its own archives, but researchers often access such papers through databases like PubMed, where such indication could be lost.)
Gary Schwitzer, founder of the watchdog website Health News Review, recalls another BMJ article that caused troubles in 2006. Around April Fool's Day, when BMJ often another humorous issue, Australian journalist and BMJ editor Ray Moynihan published a satirical article about scientists discovering a new disease: "motivational deficiency disorder." The article went on to say that 20 percent of Australians suffered from this fictional disease, and that it in some cases, it could kill people if they lost the motivation to keep breathing.
Moynihan meant to point out how many normal human behaviors, such as laziness, had been "medicalized" and targeted with unnecessary drugs, according to Schwitzer. But many journalists missed the subtext and reported on the "discovery" as real news.
Schwitzer says he sees no harm in researchers publishing ironic or sarcastic research. The problem instead lies with the people who misinterpret it. "We have journalists reporting on science that have no business doing so," Schwitzer says. "They’re in over their heads." Schwitzer says that the journalism community needs to "shut off the tsunami of unvetted science news that floods the public every day" and move toward more thorough, "slow journalism" that wouldn't make the same mistakes.
So what motivates journals to publish these kinds of humorous research articles, especially if doing so runs the risk of confusing unknowing readers—and researchers?
Ladher notes that holding the interest of readers is important for any publication, including scientific journals. In her words, BMJ's annual Christmas issue offers readers a "festive break" from the otherwise serious mix of research and commentary found in the journal's pages. "I think it adds some fun and humor in a scientifically sound way,” Ladher says. At the same time, she stresses that articles for the holiday issue go through the same full peer review process that every other BMJ research article undergoes, which involves one of the journal's medical editors and two independent reviewers and can take months.
"They all have to stack up scientifically," she says.
The attention these holiday editions help bring to studies can also be useful to researchers, says Helen Ashdown, a diagnostic researcher at Oxford University. In 2012, Ashdown published an article in the BMJ's Christmas issue finding that 97 percent of people diagnosed with appendicitis at a United Kingdom hospital reported pain when they went over any speed bumps on the way to the hospital. Ashdown intended her research to be humorous, but also useful. Last year, her work was also honored with the popular "Ig Nobel Prize," which recognizes "achievements that first make people laugh and then make them think."
Asking about speed bump pain is actually a good medical tool for doctors: It provides a quick and cheap extra test for a doctor to decide whether a patient needs immediate surgery for appendicitis, Ashdown says. This can be particularly important in areas where medical equipment and personnel are scarce. After publication, Ashdown says she has heard from many doctors who use her test in their own practices, and has received emails from people around the world who Googled about having abdominal pain when going over speed bumps and learned that they should get checked out for appendicitis.
Markt also sees real scientific potential in her humorous research on asparagus pee. The study ends by cheekily suggesting that gene editing could one day "cure" people of their asparagus anosmia. But by identifying parts of the genome where this anosmia arises from, Markt's research also helps lay the foundation for future research into the evolution of smell and what causes it to vary across individuals. She says she hopes future researchers will look into whether the genetic factors associated with anosmia could be associated with other conditions, including Parkinson's disease, which often causes people to lose their sense of smell.
At the end of the day, Markt says that outlets like BMJ's Christmas issue give researchers the opportunity to share their whimsical side in what can often be a dry and logical profession. "It's fun to be creative sometimes too," she says—as long as readers realize when a study is meant to be taken at face value, and when its authors are taking a little creative license.