A taxpayer-funded study set to find out if people can smell their own "asparagus pee."
Researchers at Harvard on two active studies that received over $3 million last year surveyed nearly 7,000 people to determine if their urine smelled funny after eating the vegetable. The results were published in the BMJ scientific journal, which uses its final edition each year to publish articles that are "quirky, amusing, and creative—but all scientifically sound."
The results concluded a "large proportion of individuals of European-American descent cannot smell 'asparagus pee'—the unpleasant odor present in urine after people eat asparagus," according to the T.H. Chan School of Public Health.
"To learn more about who can smell asparagus pee and who can't, Harvard Chan researchers surveyed 6,909 men and women of European-American descent participating in two long-term studies," the school said. "They found that 58 [percent] of men and 62 [percent] of women were unable to smell the urinary metabolites produced after asparagus consumption. Those metabolites, the authors said, create 'a rather malodorous bouquet.'"
The researchers said they have much to learn about the odor of urine.
"Outstanding questions on this topic remain," said senior author Lorelei Mucci, associate professor of epidemiology at Harvard Chan School. "First and foremost perhaps is: why such a delicious delicacy as asparagus results in such a pernicious odor, and what are the selective pressures driving genetic variations that lead to asparagus anosmia?"
The school instructed Americans to eat asparagus for health benefits, "even if they are among those able to smell the disagreeable odor afterwards."
The study also examined genetic variations that were associated with individuals who could not smell their asparagus pee, and said the findings could provide "scientists with future research directions to uncover the genetic determinants of people's overall sense of smell."
The school listed several grants from the National Institutes of Health that provided funding for the study.
Two active projects include a study using biological samples of men to examine diet and physical activity variables related to cancer that received $2,313,689 last year.
Another study is looking at the benefits of eating "plant-based" foods to battle coronary heart disease. This project received $735,491 last year.
Requests for comment on how much funding specifically went to the asparagus-pee findings were not returned.