Dr. Umar Toseeb Hello, welcome to the Papers Podcast series for the Association for Child and Adolescent Mental Health, or ACAMH for short. I’m Umar Toseeb, Professor of Psychology. My research focuses on special educational needs and mental health in childhood and adolescence. In this series, we speak to authors of papers published in one of ACAMH’s three journals. These are the Journal of Child Psychology and Psychiatry, commonly known as JCPP, the Child and Adolescent Mental Health, known as CAMH, and JCPP Advances. All listeners to this and, indeed, any of ACAMH’s podcasts, are eligible for a free CPD certificate. Do please visit acamhlearn.org for details of this, together with information on how you can access hundreds of hours of free talks, lectures, interviews, all of which you can also get free CPD certificates for. The web address is acamhlearn.org, that’s a-c-a-m-h-l-e-a-r-n.org. If you’re a fan of our Papers Podcast series, please subscribe on your preferred streaming platform, let us know how we did, with a rating or review, and do share with your friends and colleagues. Today, I’ll be speaking to the authors of the paper “Nature and Nurture in Fussy Eating From Toddlerhood to Early Adolescence Findings from the Gemini Twin Cohort,” published in the JCPP. Thank you all so much for joining me. Let’s go round and do some introduction. Ali. Dr. Ali Fildes Yeah, hi there, and my name’s Dr. Ali Fildes. I’m a Associate Professor at the University of Leeds, and I am a Researcher in child eating behaviour. Dr. Umar Toseeb Thank you. Moritz. Dr. Moritz Herle Hi, everyone, thanks for having us on. My name is Moritz Herle. I’m a Lecturer at King’s College London, and my work focuses on eating behaviours, eating disorders, and childhood obesity. Dr. Umar Toseeb Thank you. Clare. Dr. Clare Llewellyn Hi, I’m Clare Llewellyn. I’m a Professor of Psychology and Epidemiology at University College London, in the Department of Behavioural Science and Health. I am interested in how eating behaviours develop from early life and track into adult life, and the intersection between eating and feeding disorders and obesity. Dr. Umar Toseeb Thank you, and Zeynep. Dr. Zeynep Nas Hi, thanks for having me on. I’m Zeynep Nas, and I work as a Postdoctoral Researcher at University College London, and my research interests are very broad. I’m very much interested in so many different things, but, at the moment, my research interests lie in eating behaviour and, also, in eating disorders. Dr. Umar Toseeb Thank you all. Okay, let’s get straight into it. Zeynep, what is food fussiness, and why should we be concerned with it? Dr. Zeynep Nas So, food fussiness describes the tendency to eat a limited range of foods, perhaps due to pickiness or selectivity in regards to flavours or textures of foods and, really, just the reluctance to try new foods, as well. And it’s really a key behaviour that often emerges very early in childhood, and can have very important consequences for children in terms of their eating habit formation. But, also, looking more long-term, as well in terms of how these eating habits form and what those eating behaviours can transform into, potentially, looking at adolescence and adulthood, as well. And we were really interested in why some children are more fussier in terms of their eating, compared to others who are much more adventurous and have a wide, sort of, eating and food palette. And we were very interested in looking at the very early life period and, also, tracking food fussiness across childhood and, also, into early adolescence. Dr. Umar Toseeb Thank you, and I suppose this applies to any aspect of children’s development, but I want to just unpick it here for food fussiness. Where’s the cut-off between food fussiness and just preferences? Some children might just prefer certain foods, like, how do you determine what’s fussy and what’s just people liking different things? Ali. Dr. Ali Fildes It’s a really good point, and I think that’s something that, as Researchers, we’ve struggled with a little bit. So, in the context of this study, we asked parents themselves how fussy they think their own children are, and so, it’s a judgement, to an extent, so it’s comparing them to other children, say. It’s quite common for children to reject certain foods and to dislike some foods more than others, not just children, adults too, and we know from other work that we’ve done in early childhood that it tends to be plant-based foods typically that are most commonly rejected. So, there’s an element of that that you see in most children, and everybody’s got their own kind of unique patterns of preferences and likes and dislikes. But – and we’re talking about fussier children, it’s when they’ve got a narrower range of those foods that that they will eat, so, it’s they’re, kind of, rejecting more foods than they’re accepting perhaps. But there isn’t a clear cut-off where you would say this transcends from normal eating behaviour into fussiness, per se. Although there is a clinical diagnosis of ARFID, which is a condition known as avoidant/restrictive food intake disorder, where you can kind of clinically diagnose almost pathological levels of fussy eating behaviour. Dr. Umar Toseeb Yeah, and, I suppose, if we think about some of the adverse outcomes associated with fussy eating, other than the nutritional aspects of it, what are some of the negative aspects of fussy eating? Clare. Dr. Clare Llewellyn One thing probably that we’d want to do is to not alarm parents too much about fussy eating. So, it is actually quite common, up to 50% of parents would report that at least one of their children can be quite selective, or avoidant, with certain sorts of foods. And most of the time it’s not a problem and it’s absolutely fine and they get what they need, it’s when children are rejecting, for example, an entire food group, or, as Ali mentioned, a very large range of foods from that particular group, that it becomes a little bit more difficult. Sometimes, I suppose, parents worry that children are not getting the range of nutrients that they need to grow and develop as expected. Sometimes children have a slightly slower growth rate, so they might be growing more slowly on the growth chart than other children, and that’s when parents worry a little bit. Again, that’s actually not that common among children whose parents report that they are quite fussy. So, I think in terms of the longer-term effects, when it is more pronounced, when the children are not consuming, overall, as much energy, so calories, as they need to grow at a healthy weight, they grow more slowly. And there can be some nutrient deficiencies, such as iron deficiency, a zinc deficiency, but, again, these are really quite rare. Would you agree, Ali? Dr. Ali Fildes Yeah, I completely agree. Clare and I both have experiences, as the parenting side of this, not to the extent that you would, kind of, need to seek medical intervention, in the context of our children. But it’s very difficult to make that distinction, I guess, between where it transcends from, kind of, population-wide levels into more extreme levels, and I expect to an extent that’s not always that helpful, because if you can manage it then perhaps you don’t need to make that distinction. But it is a very, very common behaviour, and you certainly don’t need to be alarmed if your child’s refusing to eat certain foods, and you would typically expect that to come about as a fairly normal phase of development. There’s a lot of evidence to suggest that it starts to emerge in the second year of life and, in fact, from our own study, we found that it tends to increase over those early years, before maybe levelling off and decreasing slightly in later life. But there’s not lots of work that’s tracked into adulthood yet. I guess the next step is to find out to what extent you do grow out of it, ‘cause we’ve not found that so far. Dr. Clare Llewellyn Which is what we’re going to be doing very soon, we’re collecting that data at the moment in Gemini, which is very exciting. Dr. Umar Toseeb Moritz, did you want to come in there? Dr. Moritz Herle I agree with everything everyone has said. I guess, one thing though, we often try to talk about, when we talk about this in the media or publicly is that it’s really about picking your battles. So, I think if you’re trying to get your kids to eat one more piece of broccoli, it’s really resulting in large arguments, battles around the dinner table, one has to, kind of, think if that is, kind of, worth it. So, I think I would always think you’d rather have a positive experience at home with your kids where you have, like, fun eating together as a family. And if that means that sometimes, you know, the more fussier kids don’t eat all of the things that they’re supposedly are supposed to eat, then maybe that’s fine, I think. So, I think it’s, kind of, like, eating has a huge social component that is – brings the family together, which is, I guess, we believe is quite important for the development of the child in so many different aspects. That maybe sometimes if the focus is a lot on eating, and eating the right things or not, only eating, you know, not the right things, for example, then maybe the focus shouldn’t always be just on that, but think of it as a more broader experience, which takes the pressure off a little bit. Allow the child to be fussy for some things and then hope that they will, kind of, wane with time, which will often be the case. Of course, children who get diagnosed with ARFID, they don’t meet their nutritional needs for growth. That’s part of the diagnostic criteria, so it is quite an extreme end of those behaviours. So, these are, kind of, separate things, and if that is what you’re experiencing, then you would definitely need to get to a GP and get support with that. So, I think we need to, kind of, be – make sure that we’re, kind of, talking about these two different things a little bit separately, even though they might present, kind of, similarly on some level, but the severities are very, very different. Dr. Umar Toseeb Thank you. Clare. Dr. Clare Llewellyn The one question that constantly comes up every time you talk about fussy eating is, “When is it a problem? At what point do I need to go to the GP or speak to the Health Visitor?” And there is a bit of consensus around that, which I think is – I found quite helpful as a parent. Even as a parent who, sort of, studies this area, I never knew when it was really worrying or when it was, kind of, normal and acceptable, sort of, levels of fussiness. And I think the general consensus is, think about what your child has eaten over the last week or two, it’s never over one day, certainly not one meal, so what did they eat over the last week or two? If you’re really worried, try and keep a little diary. If, on most days, they’re eating something from each of the main food groups, so that’s fruits and vegetables, the starchy carbohydrates, dairy products, and then the protein products. So, things like meat and fish and pulses, if they’re doing that and they’re growing as expected, so that means that they’re, sort of, following their weight or BMI centile on the growth chart, they’re, sort of, tracking along on the same line, and they are energetic, they’re engaging in all the activities that you would expect them to do, and they seem happy and they seem well, you don’t need to worry. Just try to enjoy mealtimes. Try to encourage your child to, kind of, continue to try new foods, expose them to a variety of foods, and try not to get too fixated on them rejecting certain sorts of foods at the meals. Dr. Umar Toseeb Thank you for that very practical advice. Ali. Dr. Ali Fildes Yeah, I was just going to follow on from that, that’s all great advice, and I think one of the messages that we wanted to get across when we were talking about this paper, in particular, is that one of the things that is, you know, key to fussy eating is the level of anxiety, as Moritz, said, that occurs in families, both for the caregivers and for the children themselves, around being really strongly encouraged to eat foods that they’re unwilling to try. There’s – there tends to be a lot of messaging around parenting, generally, that if you do a certain set of things to – around your child that you will get a child that grows up in a particular way. So the idea that if you introduce all the right foods from the start and you – they eat a rainbow from the beginning, and you do all the right things during weaning, that you’re going to have a child that has this, kind of, broad palette. And if you have a child that is willing to do that and continues to eat a wide range of foods, you might believe as a parent that you have caused that and that you are, you know, an excellent parent and maybe look down on other parents who’ve got a child that’s rejecting those foods. Whereas, what we found in this study was that actually, there’s a strong heritable component to these behaviours, and actually, you can try and do all the best things from the start, but you still might have a child that turns around and refuses to eat any of their green veg when they hit two. And I think it’s very difficult for parents who are getting all these messages not to then blame themselves in those circumstances, and we wanted to, kind of, make it clear that while there are lots of things you can do as a family to, kind of, create the best food environment, that there may still be elements of your child’s behaviours that you can’t control or, you know, that will be there, regardless. And you just have to, kind of, manage those and accept that and actually, try not to blame yourself in those circumstances, and try not to pressure your child too much. Dr. Umar Toseeb Thank you. A fantastic broad overview and insights into fussy eating. Let’s get into the research questions of this study. Zeynep, what did you want to address before you set out? So, what were your research questions for this study? Dr. Zeynep Nas So, we were really interested in modelling the developmental progression of food fussiness, from 16 months, all the way up to about 12 to 13 years of age. So, we wanted to see phenotypically what food fussiness actually looks like throughout these developmental timepoints. And to do that, we actually used a trajectory model, which essentially tracks food fussiness from 16 months, and we had data at three years, five years, seven years and 12 to 13 years of age. And this model essentially shows us what food fussiness looks like, the average food fussiness scores, across those timepoints, in the Gemini twin study. And my team can tell a little bit more about the Gemini twin cohort and its foundations, but it’s a very large, population-based twin cohort, based in the UK, and we have very large samples across these five timepoints that I mentioned. And using this developmental trajectory model, we actually found that food fussiness scores, or the average food fussiness scores, across these timepoints, were quite stable over time. So, we see a very linear progression from 16 months all the way up to around seven years of age, and then we see a slight decline from seven years to 12 to 13 years of age. So, that was the main, sort of, aim with the first research question. And then our second aim really was to estimate the genetic and environmental contributions to food fussiness at each of these timepoints. And to do this we used a longitudinal twin model, which essentially looks at what the relative contributions of genetics and the environment is at each of these timepoints. Dr. Umar Toseeb Thank you, and, I suppose, now might be a good time to talk about the twin design and the Gemini cohort. Why use a twin design to answer this research question, or these research questions? And why the Gemini cohort? Clare. Dr. Clare Llewellyn So, twins are a very powerful design for helping Researchers to understand the relative influence of genetic factors and environmental factors on behaviours, thoughts, feelings, actions, that, kind of thing, and they separate out two sources of environmental influence, as well. So, one source is what we call “shared environmental influences,” and these are aspects of the environment that two co-twins share completely, and that make them similar to each other. So, that’s things like being of the same socioeconomic position, growing up in the same home, going to the same school, that kind of thing. And the other aspect of the environment is what we call “non-shared environmental influences,” or “unique environmental influences.” And these are aspects of the environment that you – that twins don’t share, that they experience uniquely by themselves, and they make twin pairs different from each other. So, these are things, such as having – one twin having a random illness and the other one not getting it. So, for example, a pair of twins go out for a meal, one twin gets food poisoning from that meal and the other one doesn’t, that twin then goes on to not like that particular food and the other one continues to like it, those are the sorts of random events and unique experiences. And, I guess, the basis of the twin method is that you compare how similar identical twins are, who are 100% genetically the same, with how similar non-identical twins are, who share, on average, about a 50% of their segregating genes, so that’s the bit of the genome that varies across humans. And if you see that the identical twins are much more similar for their behaviours, such as fussy eating than the non-identical twins, we assume that can only be because they’re twice as similar genetically, because everything else remains the same, insofar as the two types of twins are very well-matched for their environments. And so that’s, sort of, the basis of the study. And we established Gemini in 2007, in order to understand the genetic and environmental influences on early growth, but with a particular focus on the role of eating behaviour in that. And so, actually, one of the original hypotheses of the study was that our genes are influencing how quickly or slowly we gain weight, during childhood, and one of the ways that our genes influence our growth rate is through influencing how we respond to food and the opportunity to eat. So, some of that’s just our appetite level, some of us need to eat more or less to feel full, some of us find food very enticing and we struggle to control ourselves when certain sorts are palatable foods are around. And then there’s things like fussy eating, which is more of an avoidant eating behaviour, so finding it difficult to try new foods and eat a wide range of foods. So, these are the sorts of eating behaviours we were interested in studying, and their relationship with early growth and development. And now the twins are older, we started to look at the onset of things like eating disorders during early adolescence, as well. Dr. Umar Toseeb Thank you, and with a twin design, my understanding is whilst you can look at genetic influences, you can’t pinpoint genes, like, you’re talking about broad differences. And, also, just to clarify, the genetic influences that you can investigate using a twin design and the environmental influences explains between people differences, rather than anything about the individual themselves. Do you just want to explain that bit a bit more? Just because I think that might be helpful for the listeners to try and understand. Dr. Clare Llewellyn Yeah. Shall I pass that over to Moritz maybe? Dr. Moritz Herle I guess with the twin design, we are able to estimate individual differences in the population at the current time of when the phenotype, in this case fussy eating, was observed, so – and this is actually – you can really see that, the, kind of, let’s say malleability of these estimates across age, across development, in our paper. So, we can estimate that heritability and the shared – not-shared environmental components at different ages and we will see how those variants, as explained by those different components, will change over time, because, you know, it’s a dynamic process that is always changing. I guess what you’re trying to get at is other types of designs that actually use measured DNA. So these are often called genome-wide association studies, or genomic studies, where we actually collect DNA from the participants, and then try to find associations between genetic markers across the genome with the phenotypes of interest. This is not what we have done here, we’re using a biometric design, or, you know, quantitative trajectory design that’s using families, or family study context, which really gives us this broad sense of genetic contribution. So, the heritability estimates derived from a twin study like ours will really include all genetic variants, all types of genomic variants are included there, so, this is their variants, common variants, you know, it really is a broad sense heritability, rather than trying to identify individual genetic markers that we might then associate with that outcome. So, we are, kind of, looking at a very, kind of, broad bird’s eye view, really trying to understand the contributions that come from genetics and from environments. Where more classic genetic studies that use genetic markers really try to identify individual genetic markers on the genome, and then how – what, kind of, proteins they might be related to, and so on, this is not really the focus here. And we’re also not trying to, like, predict outcomes. So, twin studies are really fantastic to describe what is, but it’s not a really good method, or it’s not a method, at all, to predict what will be. So, only because something is highly heritable, or it has a high heritable component, doesn’t necessarily mean that, you know, that can say anything about that individual person that then an – will become a very fussy eater in adulthood. That’s not really how we think about it, we’re thinking about individual differences across the population that we’re studying, so… Dr. Umar Toseeb Yeah, that was very clear, thank you. Now, there’ll be people who are listening to this who are very interested in the analysis, and which is what I’m very excited about, so let’s get into the details of the analysis. So, one of the models that you fitted was a mixture model, and that was to map the developmental trajectory of fussy eating. Can you just tell us a bit about the benefits of using a mixture model, and what it is and why you used it? Dr. Moritz Herle Your mixer models are really perfect if you have what we call longitudinal data. By that I mean we have multiple waves of data, and where the same question is asked multiple times across time. So, in our case, the parents rate their child’s fussy eating at multiple ages, we have information on one pair of twin and their fussy eating at – across these different timepoints. I guess, in our paper we do, kind of, two types of analysis. The first one is where we just look at the means and averages and the heritability at each wave, separately, and that already is, you know, really interesting, gives a lot of insight and it’s very interesting. But it doesn’t really tell us about how the tracking of this behaviour is influenced by genetic and environmental components. And in order to describe that, let’s say, tracking or trajectory across time, the mixed model, in our case gives us three indicators that describe the trajectory across time. So, we have what is called “the intercept,” which is essentially where, on average, people start. So, on average, where is the fussy eating when we have our first measurement? Then we have the linear slope, that’s the growth, like, how fast is it changing across age? So, is it rapidly increasing, or is it rapidly going down, or is it roughly staying stable? And then we have the quadratic slope. If you think of the slope as the acceleration, the quadratic slope in our case is, like, the speed of which the behaviour, kind of, slows down again, so we can really describe where we start, where we’re going, and then how we, kind of, slow down. And, in our case, you know, it’s also useful ‘cause it produces a wonderful picture that we can look at, which is always really nice. So we can see that, overall, if you really zoom out, it is actually, kind of, a stable situation, but there’s a slight increase, as one of my colleague’s words has described, there’s a slight increase, and then by the age of seven, we have this, kind of – the behaviour becomes less and less prominent. And this is, kind of, what we almost would expect, because we imagine as a child grows up, the parents are introducing more foods, you know, they go out more, they interact with other people, they go to school, they hang out with friends’ parents, and they get introduced to more and more different foods. So, the more you get exposed, the more likely you are going to maybe express how you’re not interested in trying anything new, or how you don’t want to, you know, try that, you only want to eat this and like with – so, we, kind of, expect this behaviour to, kind of, increase with time, and then that, kind of, first resistance, or the environment maybe is adapting to you, so, you know, it becomes less of a problem. So, this is, kind of, what we expected. So, in a way, it’s quite nice that we can see that in our sample, in our population, it’s following this trajectory that we might want to expect. So it’s kind of, a proof of concept, and also shows that, you know, our measures are working in a way that we expect them to, which is always nice, so… Dr. Umar Toseeb Clare. Dr. Moritz Herle …yeah. Dr. Clare Llewellyn Moritz, I was wondering if it might be helpful to say something about the two-step approach that you can use with the mixed model, so you can take out the parameters and model them in heritability, for example, or even in, like, a regression model or something like that. Dr. Moritz Herle So, as I was describing earlier, it – the mixed model gives you these parameters. So parameters are things that we estimate from the data, so we don’t measure them, we don’t, you know, have a questionnaire that gives you that, it’s just something we calculate from all the information that we have. And these are, as I said, the intercept, so where we start off, and then the linear slope is how much we increase, and then the quadratic slope, the rate of decrease, and we can extract them, and then have these as variables in our model. So, every individual person will have their own, let’s say, score on the intercept, so they will be placed somewhere on the starting point, they will have their average how fast they increase, and then their average how fast their decrease. So, we have this information for each individual person, and then we can estimate, using our twin design, the heritability, or the environmental contributions, to the individual differences of those parameters. And that’s, kind of, like, what Clare described as a two-stage step. So, first we derive the trajectory, we pull out those estimates that we’re interested in, and then we put them back into our twin model to understand if those differences in those parameters are due to more genetic or more environmental factors. And that’s something that, in order to do this, you have to have longitudinal data and you have to have a twin sample at the same time. So, not many people can do this, so we are in this very good position that we can actually answer these quite complex, quite nuanced questions. So it’s quite exciting that we’re actually able to do this. Dr. Umar Toseeb This is a nice point to go onto the main findings. Zeynep, do you want to talk us through what the main findings are of the paper? Dr. Zeynep Nas Sure. So, just going back to our aims, our first aim, like I said, was to model the trajectory of food fussiness across time. And we actually found that food fussiness, the average food fussiness, scores in this population, was very stable across time, so all the way from 16 months to about 12 to 13 years of age. Zooming in a little bit into that trajectory parameters, we actually found that genetic differences in the population were very much contributing to where individuals started on their food fussiness scores, how their food fussiness scores changed over time, and, also, whether that change, or that linear slope, decreased or increased over time, as well. So, I think we found a very large influence of genetics on this developmental trajectory of food fussiness, across these five different timepoints. And in terms of our second aim, really zooming in on each of these timepoints, and looking at the relative influence of genetics versus the environment, we found that, over time, genetic differences accounted for more than 60% of the variation or individual differences in food fussiness, and we actually found that these genetic influences remained relatively stable, as well, across time. So, I think just zooming in on the results, we found that at 16 months, genetic differences were responsible for around 60% of the individual differences, and this continued to rise across time. So, even at 12 to 13 years of age, we see that the genetic differences accounted for about 74% of the variation of differences we see in food fussiness. So, across time, we see that genetics is accounting for a very large proportion of the variants we see in fussy eating. But this, of course, doesn’t mean that the environment didn’t contribute, at all. We actually see that the shared environment was very influential, especially in toddlerhood, so at 16 months of age, where it accounted for about a quarter of the differences that we see in fussy eating. And, also, the non-shared environment, as well, continues to increase throughout this time, so at about 13 years of age, we see that it accounts for just over a quarter of the variation, as well. So, I think this study really shows that there is a large influence of genetics, but there are these very important contributions coming in from the environment, especially looking at toddlerhood specifically. Dr. Umar Toseeb Thank you. So, very impressive cohort, very impressive set of statistical analysis, and really exciting findings. Let’s go broader, like, what – put these into context, what does this mean? Like, for people who might not be Behaviour Geneticists, might not be familiar with cohort studies, and are just people who are interested in this topic, what do these findings mean? Dr. Clare Llewellyn Ali. Dr. Ali Fildes We’ve touched upon this a little bit earlier, but that children’s fussy eating behaviour will develop, to a certain extent, independently of the environment. There is a strong genetic contribution and these behaviours will emerge, but, for example, the finding that the shared environment was strongest in the toddler years suggests that those early feeding behaviours in the parents, in terms of – and the home environment, in terms of making lots of different foods available, encouraging your child to eat lots of different colours of fruits and vegetables and those, kind of things, repeatedly offering the same foods and not giving up when your child shows a dislike for certain things, you know, not forcing them to eat it, but encouraging them and modelling that behaviour, making those foods available in their home, all might have an impact. More so in those early years, where we’ve got this stronger influence of the shared environment, and possibly less so as they grow a little bit older. So, there might be this, kind of, window of intervention there. But then, also, as children get older, it seems that, as Zeynep said, the influence of the unique environment gets a little bit stronger. So that’s, kind of, the environment outside the home, the friendships that the twins might have that are separate from one another, being in different classes of school, those, kind of, social situations, might start to impact a little more in terms of the foods that they’re choosing to eat, or not to eat in this case. So, parents might find that they find it slightly more difficult to intervene in those later stages. But I think it’s, also, key to remember that just because a behaviour has a strong genetic component, it doesn’t mean that it can’t be changed, and there is a lot of evidence for things like – repeated exposure is the most common one. So the idea that you – and I think Moritz touched upon this earlier, that you learn to like what you know, essentially, so the more that you eat something the more that you learn to like it. I think a lot of adults will have taught themselves to like certain foods or drinks, you know, beer is a common one, alcohol, often you don’t like it the first time you try it. Try it a few times and you learn to like the taste, things like olives, or coffee, things like that, that tend to be more what we think of as adult flavours, that you can, kind of, teach yourself to like, just through repeated exposure. Well, the same thing works with children. Obviously, the fussier the child, the harder it is to encourage them to try something and get that exposure in, so that can be difficult. And there’s certain techniques, kind of, trying to alleviate anxiety, taking it outside of a mealtime situation, we know that using non-food based rewards can be quite a good solution to get children to try things. So turning into a bit of a game, stickers in early childhood, things like that are all, kind of, techniques that we know might work to encourage children that are rejecting food. These findings show that there’s a very strong and stable genetic influence across childhood, but not that the environment is irrelevant, and there’s different environments at different stages might be more important when we think about trying to, kind of, modify these behaviours. Dr. Umar Toseeb Thank you, and do you have follow-up work, stemming from this project, that you’d like to tell us about? Dr. Ali Fildes Maybe this one’s for Clare. Dr. Clare Llewellyn We’re currently collecting new data on fussy eating in the Gemini cohort, and they are now 16, turning 17, and start turning 18 next year, so that’s really exciting. So, we’ll be able to track how this behaviour continues all the way from when it first emerges in toddlerhood to early adulthood, over time. But I think we’re also quite interested in understanding these sorts of fussy eating behaviours relate to the sorts of foods or the variety of foods that children are exposed to, and I think in – particularly in relation to things like the level of processing of food. So there’s a lot of interest at the moment in ultra-processed foods, and something that we’re, kind of, interested in looking at at the moment is whether children who are bit fussier tend to be offered more processed foods, ‘cause they are more readily accepted by children. But it could also be that when children are predominantly given those foods and don’t have the opportunity to branch out and try the sorts of broader range of flavours and textures in wholefoods, that they might then have a preference for those foods and reject those foods continually as they get older. So, that, kind of, I guess you’d call it a bidirectional relationship between those things, so the dietary influences on food fussiness is quite interesting to us at the moment. And Zeynep’s doing some really interesting work as part of her – a Fellowship application into ARFID. Dr. Zeynep Nas Yeah, I think the Gemini twin study is such a powerful study, just because of its longitudinal nature. So, I think we’ve got very rich data available to us, including on avoidant/restrictive food intake disorder, as well, and other disordered eating behaviours. So, I think it’s a very powerful design we have at hand here, and we’ve got very rich, detailed information available to us. And like Clare mentioned, my research focus is on ARFID at the moment, and I’d be really interested to look at how these appetitive behaviours, like food fussiness, might be related to or associated with ARFID later on in adolescence, or as these individuals are approaching adulthood, as well. Dr. Umar Toseeb It seems like it’s a watch this space, lots of exciting stuff coming up. Dr. Zeynep Nas Exactly, yeah. Dr. Umar Toseeb I first noticed this study when it was covered in various news outlets, so you got lots of media attention. What was that like? How was your experience? Dr. Zeynep Nas It was an experience, for sure. I think we’re obviously very, very happy that this study was picked up and got all of this attention from the public and from the press. So, overall, I’d say looking back at all of the interviews, and looking at all of the news outlets and what they’ve been reporting, I think it’s been very fair and accurate, so far, and we’re obviously, again, very grateful that it’s been well received by parents, as well. And I think the message has been clear, hopefully it would be helpful for a lot of parents and carers out there looking at these results and findings, and yeah, it has been impactful, I think. Dr. Umar Toseeb Clare. Dr. Clare Llewellyn I think – we were quite surprised, I think, by how much interest there was in the study, broadly, across the media, and I think it really speaks to the public interest in this topic. So, so many parents have experience of fussy eating, or their child being a fussy eater, and parents are desperate to know more about it. They want to know where it comes from, but, also, I think, more importantly, what they can do about it. So, obviously, our study showed that there’s a genetic contribution to the expression of these behaviours, why they develop in the first place. But I think the really important research that we need to do more of is to equip parents with helpful strategies, evidence-based advice, about how they can manage it in a helpful way. So a way that’s not going to contribute to more stress during the mealtimes, to parents feeling anxious, to children feeling anxious, to it, kind of, precipitating more problems. So, how that can all be managed so that families can really enjoy mealtimes and not get so bogged down in this difficult behaviour. Dr. Umar Toseeb Thank you. Just to wrap up, what’s your take home message for our listeners? Clare. Dr. Clare Llewellyn I think the key take home message is, “It’s not your fault,” to parents. If your child is expressing these fussy eating behaviours, it’s not really about anything that you’ve done wrong/ It’s not largely a reflection of parenting styles, it’s more a matter of genetic differences between children. We don’t exactly know how they work or why that is and what’s going on, that’s one of the main take home messages. And I think the other one is, that’s true, but genes are not destiny. So, just because there’s a strong genetic contribution to a child having a predisposition to be fussier than another child, it doesn’t mean there’s nothing the parents can do to help their child feel more confident about trying new foods and eating a wider range of foods. And there’s lots of other types of research, using things like randomised controlled trial designs, that have developed quite a strong evidence base around different sorts of parenting practices that can be quite helpful when you are in that situation. Dr. Umar Toseeb Thank you, that’s an excellent message to end on. Thank you all so much for taking the time. This has been a fascinating discussion. I’ve really enjoyed it, thank you so much. Dr. Clare Llewellyn Thank you. Dr. Umar Toseeb For more details on the paper, please visit the ACAMH website, that’s www.acamh.org, and Twitter @ACAMH. ACAMH is spelt A-C-A-M-H, and don’t forget to follow us on your preferred streaming platform, let us know if you enjoy the podcast, with a rating or review, and do share with your friends and colleagues.