Mennella was one of two scientists at Monell Chemical Senses Center to win a 2025 Ig Nobel Prize, the satirical counterpart to the Nobel Prize.
Philadelphia didn't take home any Nobel Prizes this year, but work illuminating how babies respond to garlic-flavored breast milk at Monell Chemical Senses Center did get recognized by its satirical counterpart, the Ig Nobel Prize.
Founded in 1991 by mathematician Marc Abrahams, the Ig Nobel Prize honors "achievements so surprising that they make people LAUGH, then THINK," according to the Massachusetts-based organization's website.
Julie Mennella, a longtime scientist at the center in West Philadelphia, and Gary Beauchamp, Monell's former director, won the prize earlier this fall for their 1991 study published in the academic journal Pediatrics that disproved popular folklore around breastfeeding.
Their study examined whether eating garlic would flavor a mother's breast milk and, if so, how a nursing baby would react to it.
At the time, breastfeeding women were often told to eat bland foods, for fear their babies would reject strong flavors. However, the study's results showed the opposite: Babies savored the garlic-flavored breast milk.
"That simple, elegant study really showed how one of the first ways we learn about foods is through what our mothers eat," Mennella said.
These early life experiences shape food preferences and influence cultural food practices around the world, she emphasized. Babies whose mothers come from cultures in which garlic is a defining flavor would have experienced garlic long before their first meal.
Mennella spoke with The Inquirer about the implications of her Ig Nobel Prize-winning work and her decades of research on flavor sciences and early nutritional programming.
The following conversation has been lightly edited for length and clarity.
We found in this study that not only did the milk get flavored with garlic, but contrary to a lot of the folklore, the babies actually liked it. They nursed longer when the milk was garlic-flavored than when it was bland and devoid of garlic.
We went on to show that when women eat garlic, the flavor of amniotic fluid also gets altered.
Through these first exposures, babies are learning about what mom is eating, what mom has access to, and what mom likes before their own first taste of solid food.
Eat the healthy foods that you enjoy because your baby's going to learn about the food. Food is much more than a source of calories. In many cases, it defines who we are as a people.
A wide variety of flavors, from vanilla to even alcohol if a woman drinks it, get transmitted and flavors the milk. If women smoke, the tobacco flavor does, too. So it's not only what you eat, but what you breathe.
There's a great story about the European rabbit (an animal that nurses), where they tagged the mother's diet with juniper berry. What they were able to show is that in a group where the mothers ate juniper berry during either pregnancy or lactation, once those young rabbit pups left the nest, they were more likely to forage on juniper berry.
So, she's telling them, 'These are the foods that are out there. I'm eating them. They're safe.' It's really a very elegant, sustainable behavior, how moms transmit this information about the foods in the environment. She's teaching her young and giving them an advantage early on.
Depending on the size of the chemical, some will get in fast. Garlic gets in a couple hours after the mom eats it, and then if she stops eating, it's out of the milk like four or five hours later. The sensory experience of that baby is changing throughout the course of the day, day to day, depending on what she eats.
I've gone into so many different directions of looking at not only early flavor learning, but also nutritional programming. I also looked at the taste of medicine in children, looking at individual differences because taste is the primary reason for non-compliance. Children have a harder time because they can't encapsulate the bad taste in a pill or tablet, so liquid medicines are particularly difficult.
One study where we looked at variation in the taste of pediatric Motrin (among adult participants) was really interesting. Some people experience a tingle when they taste it. Others don't. It makes you think that how one child tastes Motrin isn't like how another does. If you don't experience the tingle, or this burning sensation, all you taste is a sweet liquid, and those are the children that may be at risk of over-ingestion.
I serendipitously found that another flavor that gets transmitted is alcohol, and that became a whole new area of research.
We found that when women just have the equivalent of one or two glasses of wine or beer, not only did the alcohol get transmitted, but it flavored the milk. That became a lead article in the New England Journal of Medicine.
At that time, there was talk about a folklore that women should drink when they're breastfeeding, so they would make more milk. And contrary to that folklore, they actually made less milk.
It was so nice to celebrate science. That's really what that award does: It uses humor to teach about science.