Fussy eater or genetics? Pint of Science talk May 20
Ever wondered why some people can’t get enough of broccoli while others can’t stand the sight of it? Well, it could be less about being a fussy eater and more about our genes, according to Dr Rachel Hagan, a LJMU psychologist and presenter at the Pint of Science public talks in Liverpool later this month. Pint of Science runs at Murphy’s Distillery and Bar, Liverpool from Monday 19 to Wednesday 21 May.
We put our questions to Rachel (pictured below) about taste, smell and the future of food!
Q. Is fussy eating a thing or … what?
“Fussy eating is often linked to genuine sensory sensitivities rather than just being ‘picky’. Foods like bitter greens or anything mushy or slimy can be genuinely unpleasant, and this can be due to a range of factors, including genetics, sensory processing differences, or early feeding experiences. Children actually experience flavours more intensely than adults because they have more taste buds and a heightened sense of taste and smell. So, flavours we might find mildly bitter or textures we barely notice can feel overwhelming to them.
Q. What can parents do apart from get exasperated?
“It’s really helpful for parents to try to understand what it is about a particular food that their child finds difficult, is it the taste, the texture, or the smell? Research shows that repeated, low-pressure exposure (without forcing it) can increase acceptance over time. That might mean offering a disliked food in different forms or simply placing it on the plate without any pressure to eat it. Involving kids in food prep or making mealtimes fun and interactive can also help reduce anxiety and build curiosity about new foods. My advice is to avoid turning food into a battle. Most importantly, preferences change over time, so patience is very important.
Q. Don’t we all taste things in the same way i.e. something bitter is yuck and something sweet is mmm? Or is it a very individual experience?
“Taste is actually a really personal experience. Things like your upbringing and what you were fed as a child can shape how you respond to different flavours. Chilli, for example, might be way too much for one person but totally comforting for someone who grew up with spicy food. Biology also plays a big role. Some people are what we call supertasters, meaning they naturally experience certain tastes much more strongly than others. This often comes down to having a higher density of papillae on the tongue, those little bumps that house your taste buds. More papillae mean more taste receptors, so flavours like bitterness are perceived much more intensely. This means that foods like broccoli, cabbage, or coffee can taste overwhelmingly bitter to them, while someone else might barely notice it. It’s not just about being picky, their actual sensory experience is different because of their genes.
Q. Did you research this?
“Yes, in my research, we found that supertasters didn’t just find bitter tastes more intense – they also rated astringent and cooling menthol sensations as stronger. So, these differences go beyond just taste and affect the whole mouthfeel experience. That’s why one person’s favourite food might be unbearable to someone else, and that’s completely normal.
Q. So is hot food actually hot?
“People often say that spicy food ‘burns their taste buds’, but that’s not the case. That burning sensation isn’t actually taste at all. It’s picked up by the trigeminal nerve, which is responsible for detecting things like temperature and pain in the mouth. So, when you eat spicy food, you’re actually triggering a pain response. Regular exposure to spicy food can lead to sensory adaptation, making that burning sensation feel less intense over time. So, it’s not that some people have a higher pain threshold, their sensory system has just adjusted over time.
Q. What exactly is oral multisensory processing?
This is how multiple senses work together to create the sensory experience of eating and drinking. While we often use the word ‘taste’ to describe everything we experience when we eat, taste technically only refers to the five basic sensations: sweet, salty, sour, bitter, and Umami. But the full experience of flavour involves much more than that. It includes aromas from food, texture and temperature in the mouth, and even sound (like the crunch of crisp). These different sensory inputs are integrated in the brain to form what we recognise as flavour. So eating is a multisensory process, not just something that happens on the tongue.
Q. As a psychologist, what are you reading into these findings?
“One of the big questions I explore is how individual differences, both sensory and psychological, influence what we like, want, or avoid. Flavour isn’t just about the senses; it’s shaped by emotion, memory, attention, and past experience. These responses often operate at an implicit level, outside of conscious awareness, giving us insight into how people process reward, how sensitive they are to certain sensory cues, and how this links to behaviour. So, while we can't determine someone's full personality from how they respond to a taste or smell, we can learn a lot about how they experience the world. For example, people who are more sensitive to certain flavours might also show stronger emotional reactions, patterns that can relate to broader traits like sensory sensitivity or reward responsiveness. In that sense, our flavour preferences can offer a subtle but meaningful window into psychological differences between individuals.
Q. What is the message from your talk? What do you want people to take away?
The big takeaway from this talk is that flavour isn’t some universal thing we all experience the same way, it’s actually really personal. You might love something that someone else can’t stand, and that’s not just about being picky , it’s about biology. Things like taster status can totally change how you experience food and drink. And rather than just asking people what they like, we can also measure their responses more objectively using physiological tools like facial EMG, which picks up on small muscle movements that indicate emotional reactions to taste, so we can measure a person’s emotional response to a food without asking them. So, I want people to leave this talk with a new appreciation for just how complex, individual, and fascinating ‘flavour’ really is.
Q. Where is the science going in this topic?
“My PhD was in part funded by the Oral Health Department of Glaxo Smith Kline (GSK). They are interested in funding this sort of research because they want their products to be successful in a highly competitive global market. They can’t just be functionally effective, they need to be liked by consumers. So they want to understand if different populations may have different responses to their products. My research explores not just what people say they like, but how they respond on a more automatic, even unconscious level. So, we measure things like facial muscle activity or reaction times to assess emotional responses, without relying on self-reported data. This research is becoming especially relevant in industries like food, drink, and oral health. People respond very differently to products depending on how sensitive they are to certain flavours. In short, there’s a growing interest in more personalised approaches, products that aren’t one-size-fits-all but tailored to how different people experience flavour. The more we understand about these sensory and psychological differences, then industries can create products that people genuinely enjoy, stick with, and even benefit from.
View the full Pint of Science line-up.