Why you should care
Because what you give your body might affect how much you give to others.
At night, you don’t count sheep — you envision the fluffy, steamy omelet that will nestle with your morning sesame bagel. You feel cautiously OK about confessing these particular nighttime thoughts to your spouse. After all, we’ve known for a decade that an egg-a-day actually won’t send your cholesterol levels skyrocketing. And now all you egg eaters might be getting an unexpected ego boost.
Eating eggs could make you more generous.
Researchers at Leiden University in the Netherlands found that a nutrient in eggs called tryptophan increased the likelihood that participants would donate to charity. In a study published in Frontiers in Psychology last December, they traced the do-gooder behavior to tryptophan’s crucial role in producing serotonin, aka the “feel-good” hormone. “In a way, we are what we eat,” Leiden University cognitive psychology Ph.D. student Laura Steenbergen, who led the study, tells OZY in an email.
Earlier studies have linked serotonin to charitable giving and other behaviors that benefit others, and lowered levels of the hormone to social isolation and aggression. Since our bodies make serotonin from tryptophan — abundant in not only eggs, but also in fish, milk, soy and cheese — researchers wanted to know whether tryptophan supplements could boost charitable giving.
So Steenbergen and her colleagues recruited 32 men and women and fed half a supplement containing roughly the same amount of tryptophan in three eggs and the other half a placebo. They then gave each of them 10 euros, or around $10.50, and asked whether they’d like to give part of their reward to charity, presenting them with a table of donation boxes from UNICEF, Greenpeace and other organizations.
On average, participants who had received the tryptophan supplements dropped one euro (about a dollar) into the boxes, or
as much as those in the placebo group.
The researchers aren’t sure exactly how tryptophan promotes generosity, but the 2011 finding that oxytocin — the “warm and fuzzy” hormone, released after hugging and sex — also increases the likelihood of charitable donation offers some clues. Since the brain region where tryptophan is turned into serotonin sends signals to the region that releases oxytocin, serotonin might amplify oxytocin levels.
But Jorge Barraza, a research assistant professor in the School of Social Science, Policy & Evaluation at Claremont Graduate University, notes that in similar studies of generosity, around 5 percent of participants tend to be highly generous due to chance alone — enough to tip the balance between the tryptophan and control groups in a small sample like Steenbergen’s. He also wanted to see “a proper control treatment,” or a nutrient like glucose instead of just a placebo to “disentangle whether it really is serotonin and not just depriving people of nutrition” that’s influencing their generosity.
Next up, Steenbergen and her colleagues want to further understand how consuming tryptophan affects the medial prefrontal cortex, a brain region involved in social behaviors like charitable giving. While it’s too early to recommend gorging on Paas-dyed eggs for the sake of humanity, the findings still show “how important it is to eat a proper diet,” Barraza says. “Skipping a meal might have more of an effect than leaving you a little hungry.” It might leave you little stingy too.