Babies respond positively to smell of foods experienced in the womb according to study co-led at Aston University

Feb 13, 2025

4 min

Jackie Blissett


  • Babies whose mothers took kale or carrot capsules when pregnant responded more favourably to these smells
  • The research shows that the process of developing food preferences begins in the womb, much earlier than previously thought
  • The research follows up on an earlier study


Babies show positive responses to the smell of foods they were exposed to in the womb after they are born, according to a new study.


The findings, led by Durham University, UK, could have implications for understanding how healthy eating habits might be established in babies during pregnancy. The research included scientists from Aston University, UK, and the Centre national de la recherche scientifique (CNRS) and University of Burgundy, France. It is published in the journal Appetite.


Researchers analysed the facial expressions of babies who had been repeatedly exposed to either kale or carrot in the womb after birth. Newborns whose mothers had taken carrot powder capsules when pregnant were more likely to react favourably to the smell of carrot. Likewise, babies whose mothers had taken kale powder capsules while pregnant reacted more positively to the kale scent.


Research co-lead author and supervisor Professor Nadja Reissland, of the Fetal and Neonatal Research Lab, Department of Psychology, Durham University, said:


“Our analysis of the babies’ facial expressions suggests that they appear to react more favourably towards the smell of foods their mothers ate during the last months of pregnancy. Potentially this means we could encourage babies to react more positively towards green vegetables, for example, by exposing them to these foods during pregnancy.


“In that respect, the memory of food the mother consumes during pregnancy appears to establish a preference for those smells and potentially could help to establish healthy eating habits at a young age.”


This study is a follow-up to a 2022 research paper where the researchers used 4D ultrasound scans at 32 and 36 gestational weeks to study foetal facial expressions after their pregnant mothers had ingested a single dose of either 400mg of carrot or kale capsules. Foetuses exposed to carrot showed more “laughter-face” responses while those exposed to kale showed more “cry-face” responses.


For the latest study, the researchers followed up 32 babies from the original research paper – 16 males and 16 females – from 36 weeks gestation until approximately three weeks after birth.


Mothers consumed either carrot or kale capsules every day for three consecutive weeks until birth. When the babies were about three weeks old, the research team tested newborns’ reactions to kale, carrot, and a control odour.


Separate wet cotton swabs dipped in either carrot or kale powders, or water as the control, were held under each infant’s nose and their reaction to the different smells was captured on video. The babies did not taste the swabs. Scientists then analysed the footage to see how the newborns reacted and compared these reactions with those seen before the babies were born to understand the effects of repeated flavour exposure in the last trimester of pregnancy.


The research team found that, from the foetal to newborn period, there was an increased frequency in “laughter-face” responses and a decreased frequency in “cry-face” responses to the smell the babies had experienced before birth.


Humans experience flavour through a combination of taste and smell. In foetuses, this happens through inhaling and swallowing the amniotic fluid in the womb.


Research co-lead author Dr Beyza Ustun-Elayan carried out the research while doing her PhD at Durham University.


Dr Ustun-Elayan, who is now based at the University of Cambridge, said:


“Our research showed that foetuses can not only sense and distinguish different flavours in the womb but also start learning and establish memory for certain flavours if exposed to them repeatedly. This shows that the process of developing food preferences begins much earlier than we thought, right from the womb. By introducing these flavours early on, we might be able to shape healthier eating habits in children from the start.”


The researchers stress that their findings are a baseline study only. They say that longer follow-up studies are needed to understand long-term impacts on child eating behaviour. They add that further research would also need to be carried out on a larger group of infants, at different points in time.


They say that the absence of a control group not exposed to specific flavours makes it challenging to fully disentangle developmental changes in the babies from the effects of repeated flavour exposure. Future research should also factor in post-birth flavour experiences, such as some milk formulas known to have a bitter taste, which could impact babies’ responses to the smell of bitter and non-bitter vegetables.


The research involved the children of white British mothers, and the researchers say that future studies should be widened to explore how different cultural dietary practices might influence foetal receptivity to a broader array of flavours.


Research co-author Professor Jackie Blissett, at Aston University’s School of Psychology, said:


“These findings add to the weight of evidence that suggests that flavours of foods eaten by mothers during late pregnancy are learnt by the foetus, preparing them for the flavours they are likely to experience in postnatal life.”


Research co-author Professor Benoist Schaal, National Centre for Scientific Research (CNRS)-University of Burgundy, France said:


“Foetuses not only detect minute amounts of all types of flavours the mothers ingest, but they overtly react to them and remember them while in the womb and then after birth for quite long times. In this way, mothers have an earlier than early teaching role, as the providers of the infant’s first odour or flavour memories.”


Visit https://doi.org/10.1016/j.appet.2025.107891 to read the full research paper in Appetite.

Connect with:
Jackie Blissett

Jackie Blissett

Professor of Psychology

Professor Blissett has a interest in children’s fussy eating including poor fruit and vegetable acceptance, emotional eating, and obesity.

Feeding and Eating BehaviourPsychologyChildhood Eating BehaviourFussy EatingDevelopmental Psychology

You might also like...

Check out some other posts from Aston University

3 min

Aston University research: Parents should encourage structure and independence around food to support children’s healthy eating

Dr Katie Edwards studied the feeding practices of parents of children with ‘avid’ eating traits, which can lead to obesity Focusing on health or deciding when it is time for a meal or snack helps parents to use supportive feeding practices. Supportive feeding practices could include involving children in decisions about food, or sitting together for mealtimes New research from Aston University has shone a light on the best ways for parents to encourage healthy eating in their children. The team of academics from Aston University’s School of Psychology, led by Professor Jacqueline Blissett, with Dr Katie Edwards as the lead researcher, looked at the meal- and snack-time practices of parents of children with ‘avid’ eating behaviours. ‘Avid’ eaters, who make up around 20% of children, particularly love food, are often hungry and will eat in response to food cues in the environment and their emotions, not just when they are hungry. They are the most susceptible to obesity and therefore encouraging a healthy, balanced diet is vital. Feeding children with avid eating behaviours can be challenging and the researchers wanted to understand how factors in everyday life, such as parent mood or eating situations, influence the feeding practices that parents use. Understanding this can help to create better support for families around meal and snack times and reduce the risk of children developing obesity. Dr Edwards says that the research shows that when parents prioritise children’s health or decide when it is time for a meal or snack, parents are more likely to use supportive feeding practices which create structure around meal or snack times or encourage children to be independent with their food choices. For example, parents could sit and eat with their children, choose what food is available for their children, or involve children in decisions about what food to eat. She adds that there are three main things that parents can do to help encourage healthy eating behaviour. The first is to focus on health, by providing nutritious and balanced meals. The second is to ensure a calm and positive atmosphere during eating occasions. The final recommendation is that parents should take the lead on setting meal- and snack-times, with a good structure being three meals and two snacks a day. These recommendations are linked to parents’ use of supportive feeding practices which are known to encourage children’s healthy eating. To carry out the research, the team recruited parents of children aged 3-5 with avid eating behaviour and asked them to download an app to their smartphones. The app sent four semi-random reminders per day for a 10-day period, asking them to complete a survey with information about mood and stress levels. Every time a child had a meal or a snack, or asked for food, parents completed another survey to give information about feeding practices (including those which give children structure, or independence, around food), mealtime goals (such as prioritising healthy eating), and information about the mealtime setting (such as the atmosphere). Previous research from this team at Aston University identified four main eating traits in children. As well as ‘avid’, the other traits, not studied here, are ‘typical’ eaters, who have no extreme behaviours, ‘avoidant’ eaters, who are extremely fussy, and ‘emotional’ eaters, who eat in response to emotions but do not necessarily enjoy food in the way that avid eaters do. Dr Edwards was also involved in the team’s research at Aston University that showed that parents’ eating behaviour influences that of their children. Dr Edwards said: “Given the challenges that parents may face and the risk of childhood obesity, we will use these findings to develop feeding support for families. Encouraging parents to use feeding practices which provide structure around meal and snack times, or promote children’s independence with food, could be helpful for supporting children’s healthy eating. Read the full paper in the International Journal of Behavioral Nutrition and Physical Activity at https://doi.org/10.1186/s12966-025-01768-x.

3 min

Aston University optometrist develops app with the best easy blinking exercises to improve dry eye symptoms

Dry eye disease is a common condition affecting one-third of the adult population and one-in-five children Professor James Wolffsohn researched the most effective blinking exercises to reduce discomfort, involving a close-squeeze-blink cycle He developed the MyDryEye app in collaboration with Alec Kingsnorth and Mark Nattriss to help sufferers An Aston University optometrist, Professor James Wolffsohn, has determined an optimum blinking exercise routine for people suffering with dry eye disease, and has developed a new app, MyDryEye, to help them complete the routine to ease their symptoms. Dry eye disease is a common condition which affects one-third of the adult population and one-in-five children, in which the eyes either do not make enough tears, or produce only poor-quality tears. It causes the eyes to become uncomfortable, with gritty- or itchy-feeling eyes, watery eyes and short-term blurred vision. It is more common in older adults and can be exacerbated by factors including dry air caused by air conditioning, dust, windy conditions, screen use and incomplete blinks, where the eye does not fully close. Professor Wolffsohn is head of Aston University’s School of Optometry and a specialist in dry eye disease. While it has long been known that blinking exercises can ease the symptoms of dry eye disease, the optimum technique, number of repetitions and necessary repeats per day are unclear. Professor Wolffsohn set out to determine the best exercises. His team found that the best technique for a dry eye blinking exercise is a close-squeeze-blink cycle, repeated 15 times, three times per day. Participants found that while they were doing their exercises symptom severity and frequency decreased, and the number of incomplete blinks decreased. Within two weeks of stopping the exercises, their symptoms returned to normal levels, showing the efficacy of the exercises. To carry out the work, Professor Wolffsohn’s team ran two studies. For the first, they recruited 98 participants, who were assessed for dry eye symptoms before and after the two weeks of blinking exercises. Participants were randomly allocated different blinking exercises to determine the most effective. A second study with 28 people measured the efficacy of the blinking exercise. Once the optimum blinking routine had been developed, Professor Wolffsohn worked withAlec Kingsnorth, an engineer and former Aston undergraduate and PhD student, and Mark Nattriss, business manager of his spin-out company, Wolffsohn Research Ltd, to develop the app, MyDryEye, which is freely available on Android and iOS operating systems. The app allows users to monitor their dry eye symptoms, assess their risk factors, add treatment reminders and monitor their compliance, complete the science-based blink exercises and find a specialist near them. Professor Wolffsohn says that the blinking exercises should be carried out as part of a treatment programme which could also include the use of lipid-based artificial tears, omega-3 supplements and warm compresses. Professor Wolffsohn said: “This research confirmed that blink exercises can be a way of overcoming the bad habit of only partially closing our eyes during a blink, that we develop when using digital devices. The research demonstrated that the most effective way to do the exercises is three times a day, 15 repeats of close, squeeze shut and reopen – just three minutes in total out of your busy lifestyle. To make it easier, we have made our MyDryEye app freely available on iOS and Android so you can choose when you want to be reminded to do the exercises and for this to map your progress and how it affects your symptoms.” Read the full paper, ‘Optimisation of Blinking Exercises for Dry Eye Disease’, in Contact Lens and Anterior Eye at https://doi.org/10.1016/j.clae.2025.102453.

2 min

Aston University researchers to take the first steps to find out if AI can help policymakers make urban mobility more sustainable

Researchers to explore how AI can help urban mobility planners They are to investigate AI-driven policy tools’ potential to create greener cities Project to benefit from expertise of five European universities. A European group of researchers led by Aston University is taking the first steps to explore how AI can help urban mobility planners. As city populations grow causing strain on resources, the experts are to investigate AI-driven policy tools’ potential to create greener cities. The team have received £10,000 in funding from the British Academy which they hope will set them on the road to further research. Taking part in the project will be experts from University College London, Ruralis University in Norway, the University of Turin, Italy and Lisbon University Institute, Portugal. Dr Dalila Ribaudo from the Centre for Business Prosperity at Aston Business School and Dr Alina Patelli from the Aston Centre for Artificial Intelligence Research and Application will co-lead a UK-EU consortium consolidation project. The interdisciplinary project will benefit from expertise in applied business and specialist insight into global economics, policymaking and urban transport planning. Dr Patelli said “Policymakers and society could all benefit from our research into innovative ways of managing the strain on urban infrastructures and resources. "The AI-powered policy tools we are developing are meant to support decision managers at all levels of urban governance with reducing emissions, optimising transportation as well as predicting and preventing environmental hazards. Such changes would improve the quality of life for the millions of people living in towns and cities across the UK, Europe and, in the long term, the entire world.” Following the successful bid for the British Academy pump priming grant the team will apply for Horizon Europe funding to continue developing impactful AI-driven policy tools for greener cities.

View all posts