How taste preferences form: can you “teach” your child to love vegetables

How do we perceive taste?

When we eat, our taste receptors pick up 5 basic tastes: sweet, sour, bitter, salty, and umami.

However, for the full perception of food we also involve the smell receptors, which pick up odors. That is why, when our nose is blocked, food seems bland — we cannot fully sense its aroma.

Notably, odor molecules reach the receptors in our nose not only through the nose, but also through the nasopharynx while we chew and swallow food. This process is called retronasal breathing, and it plays an important role in perceiving the complex nuances of a food’s taste.

So when we talk about taste, it is worth understanding that this concept includes not only the taste receptors on the tongue, but also the smell receptors.

In fact, the perception of food is an even more complex process, which includes not only the integration of stimuli such as taste and smell, but also depends on trigeminal sensations, the texture of the food, and even its appearance.

Trigeminal sensations are those that arise from stimulation of the trigeminal nerve, which is responsible for sensitivity to pain, temperature, and certain chemical substances in the mouth. These can be sensations of cold, astringency, burning, and so on. They add depth to the taste experience and create a richer perception of food.

It is worth noting that all these sensations together create what in English is called “flavor”. In Ukrainian, unfortunately, there is no separate word that would fully describe the combination of all these properties of food.

The influence of biological factors

It is known that inherited factors play a significant role in shaping taste preferences. They affect how different tastes are perceived, they determine a tendency to prefer certain tastes, and they shape openness to food variety in general. Let’s look at the main ones below.

1. Innate taste preferences

Many studies confirm that babies have an innate tendency toward sweet, salty and umami tastes, and react with aversion to bitter and sour. This conclusion is often based on analyzing the amount of liquid consumed and babies’ facial reactions to different tastes.

Interestingly, unlike sweetness, which is preferred from birth, babies’ response to salty taste changes over the first months of life. Studies show that at 2-3 months babies show no noticeable changes in sucking behavior in response to salt solutions, which suggests indifference to the salty taste or even rejection of it. At the same time, by 3-4 months they are able to tell saltiness apart and begin to prefer moderately salty solutions (sodium chloride) over plain water.

Research has shown that a baby becomes familiar with tastes and aromas before birth. Taste buds form between weeks 8 and 15 of pregnancy, which allows the fetus to distinguish different tastes. In the third trimester, the ability to distinguish smells also develops. When the fetus breathes in and swallows amniotic fluid, which is known to take on the aroma and flavor components of the food the mother eats, it already begins to perceive these qualities. So by the third trimester of pregnancy the fetus’s taste and smell receptors are already developed enough to sense tastes and smells. After birth, these receptors keep on refining.

A study carried out by scientists at Durham University showed that babies in the womb exposed to the taste of carrot more often displayed smile-like expressions, while exposure to the taste of kale produced cry-like expressions. In addition, it was found that introducing a sweet stimulus into the amniotic fluid stimulated swallowing movements, while introducing a bitter stimulus reduced the intensity of such movements.

These findings point to an ability to distinguish tastes even before birth.

What are these preferences for?

It is believed that taste preferences shaped by evolution help babies orient toward the most useful and safest food sources. The sweet taste, naturally associated with energy and nutrients, draws babies to breast milk, which is an important source of vitamins, sugars and fats. The sweet taste also has a calming effect on babies and can even reduce the sensation of pain. Studies show that introducing a sweet stimulus can reduce pain responses in babies, adding to their comfort during unpleasant procedures or situations.

On the other hand, aversion to bitter taste is a natural protective mechanism, since many poisonous substances and toxic compounds taste bitter. This allows babies to avoid dangerous foods. Similarly, unpleasant reactions to sour tastes help prevent eating spoiled food or unripe fruit, which can be harmful to health.

2. Genetic sensitivity to certain tastes

Besides an innate attraction or aversion to tastes, there is also individual sensitivity to the basic tastes.

In 1931, the chemist Arthur Fox accidentally scattered PTC (phenylthiocarbamide) powder, and his colleague instantly felt a strong bitterness, while Fox himself felt nothing. This led him to the idea of individual differences in taste perception. He ran an experiment among relatives and friends: some felt a pronounced bitterness, others only a faint aftertaste, and some felt nothing at all.

That is how it was discovered that the perception of bitter taste varies and is inherited.

In 2003, scientists identified the TAS2R38 gene, which is responsible for sensitivity to bitter compounds. It turned out that there are two main variants of this gene, and one makes a person sensitive to bitter compounds. This experiment explained why some people dislike broccoli and other cruciferous vegetables, while others eat them with pleasure.

According to statistics, in the US about 25% of people describe PTC as very bitter, 50% have medium sensitivity to it, and 25% do not taste it at all.

Interestingly, fat taste, which until recently was not considered a separate basic taste, is now being actively researched in science. Sensitivity to fatty acids, which is linked to receptors such as CD36, allows us to judge the fat content of food. The ability to sense fat taste is an evolutionarily important skill, because fats are the main source of energy, and this helped our ancestors choose calorie-rich foods to survive.

There is reason to believe that sensitivity to fat taste varies from person to person: some perceive it more strongly than others. There are also variations in how other tastes are perceived, such as sweet, salty, sour and umami, but the degree of genetic sensitivity is most pronounced for bitter taste.

3. Food neophobia

Food neophobia is a fear of, or a refusal to eat, new foods or foods served in a new way. This process is a normal stage of a child’s development and is seen in 50-75% of children aged two to six years.

Over time this phase gradually fades, but in some cases it can persist into adulthood. Notably, new foods are often rejected before they are even tried, at the stage when they are served, because a dislike of the textural and visual characteristics of food is the strongest factor contributing to food neophobia in young children.

In general, children more often accept familiar food or food that tastes sweet, since this is linked to their experience of breast milk or formula.

This mechanism is an adaptation for our ancestors’ survival, as it made it possible to avoid potentially poisonous or dangerous foods (poisonous mushrooms, berries and so on) during the period when a child began to actively explore the world, which usually starts in the second year of life.

4. Neurodiversity

Eating involves all eight sensory systems of our body: visual, auditory, taste, smell, tactile, vestibular, proprioceptive and interoceptive. Each of them plays an important role in perceiving food and interacting with it, providing the sensory processing needed for comfortable and safe eating.

In neurodivergent people, in particular people with autism spectrum disorder (ASD) or attention deficit hyperactivity disorder (ADHD), this process can be more difficult. They often face difficulties with sensory integration, which affects the perception of taste, smell, texture and other characteristics of food, and often shapes restricted eating behavior.

For example, hypersensitivity to certain textures or smells can cause a strong aversion to foods, such as vegetables with a coarse or fibrous structure or dishes with a strong smell. The bright colors of some foods can be over-stimulating, and crunching sounds during a meal can cause discomfort or even pain. All of this significantly affects how acceptable food is, regardless of how it tastes.

Some neurodivergent people, on the contrary, seek more intense sensations. This can show up as a craving for bright, sour, overly salty or spicy-hot foods. Such behavior helps them meet their need for stronger sensory stimulation.

The influence of the surrounding environment is no less important. Noise, bright light, a large number of dishes on the table or a general overload of stimuli during a meal can cause difficulty concentrating and raise anxiety levels, which in turn leads to a reduced appetite or an impaired ability to feel hunger and fullness cues.

Neurodivergence, although not always, is often hereditary, driven by genetic factors. That is exactly why it is included in the list of genetic factors that influence individual features of sensory and food perception.

5. Other genetic features in the perception of taste and smell

Eating behavior is strongly influenced by genetically determined individual features of smell and taste. In humans, about 400 genes are responsible for smell receptors, and variations in these genes explain why the same smell can be pleasant for some people and repulsive for others. Such differences undoubtedly affect food preferences.

Just like with smell, the number and sensitivity of taste receptors differs from person to person. For example, there is a group of people known as supertasters — they have heightened sensitivity not only to bitter, but also to sweet, salty, texture, smells and even sounds connected with food. This affects not only what exactly they choose to eat, but also how much pleasure they get from the process of eating.

Despite a widespread belief, supertasting is not linked to a greater number of taste receptors and is not a total hypersensitivity to all tastes. That general condition has a different name — hypergeusia. There are other conditions too, such as reduced or distorted perception of taste or smell (anosmia, dysgeusia). All of them are often inherited, which once again underlines how important individual differences are and how they shape eating behavior from an early age.

The influence of environment

Inherited factors largely shape our taste preferences and eating behavior. However, this behavior is not formed by innate biological features alone. The influence of environment matters just as much — upbringing, cultural traditions and early experience all significantly shape our eating habits. Next we will look at how early experience affects a child’s food preferences, and how we can help them accept solid foods more willingly.

1. A varied maternal diet during pregnancy and breastfeeding as a first taste experience

As already mentioned, your baby gets to know different tastes before birth, because flavor molecules from the mother’s food pass through the amniotic fluid.

The taste of breast milk also changes depending on the mother’s diet. All of this lets your baby get used to different tastes even before solid foods.

One experiment found that when mothers ate garlic, the taste and smell of their breast milk changed, which in turn prompted the infants to spend more time at the breast and to suck more actively. In addition, studies have shown that babies are able to remember the flavors of breast milk and amniotic fluid, and later recognize these tastes when solid foods are introduced.

And although this does not guarantee that your baby will immediately like a food with a familiar taste, it lowers resistance to a new taste and increases the likelihood that your baby will accept it.

For example, babies whose mothers drank carrot juice during pregnancy or breastfeeding ate carrot-flavored cereal with more enjoyment, or at least showed more positive reactions to this familiar taste.

There is now reason to believe that the more vegetables a mother eats during pregnancy and lactation, the more a baby tends to accept a wide range of foods when solid foods are introduced, and this acceptance is not limited to specific tastes only.

As for the long term, some studies have found a direct link between breastfeeding, the mother’s diet and how this affects a baby’s taste preferences: the more vegetables a mother eats in the first 3 months after giving birth, and the longer she breastfeeds her baby, the greater the likelihood that her child will go on to eat large amounts of vegetables. What is more, breastfed children are mostly less fussy about food at an older age.

2. The influence of formula feeding

Unlike the varied taste experience of breastfeeding, formula-fed babies usually get a stable, less variable taste. However, even among formulas there are big differences in taste, and babies get used to the particular taste of their formula. For example, babies fed an extensively hydrolyzed formula accepted foods with the bitter and sour tastes typical of this type of formula better, including broccoli and other cruciferous vegetables.

This early experience also shapes food preferences, but unlike breastfed babies, formula-fed babies can get used to tastes that are not present in the family diet, so their liking may not be supported by the food eaten at home.

Interestingly, for formula-fed babies there is a period of sensitivity to the taste of extensively hydrolyzed formula during the first four months. At first they may show no interest in this taste, but over time acceptance of the taste grows, and this effect lasts for months and even years after the feeding has stopped.

These results confirm the importance of early acquaintance with a variety of tastes, even unacceptable ones, because this has a long-lasting effect on a child’s taste preferences.

3. Dietary variety and repeated offering

In the first years of life a child is especially open to new tastes and textures — this is the so-called “window of opportunity” for food, which gradually fades as they reach the age of 24 months. That is why, whatever the type of feeding, it is important to offer your baby a variety of foods, to build a broad palette of taste preferences and minimize signs of food neophobia.

The results of one study showed that children who had a wide variety of vegetables at the start of solid foods later ate more new vegetables, had a higher level of acceptance of them, and were more willing to try new vegetables. These effects lasted up to 6 years of age, which highlights the importance of introducing a variety of vegetables early for building healthy eating habits in the long term.

It is worth noting that at the first meeting with a new food you should pay attention not so much to your baby’s facial expressions as to their willingness to try the food. A change in facial expression may appear much later than a change in the amount of food eaten, so even if your baby makes faces (scrunches up their face, frowns), it does not mean they dislike the food.

Do not underestimate the power of offering a food again: even though your baby refused a food on the first try, it does not mean they will not accept it later. It is known that children need at least 8-10 tries before they get used to a new taste.

In addition, serving new foods alongside already familiar ones is considered an effective way to gradually broaden your baby’s food preferences. Offering purées made from the foods the mother ate during pregnancy and breastfeeding can make the introduction to solid foods easier, and adding breast milk or the usual formula to your baby’s porridge can become a kind of “bridge” to accepting more complex tastes.

4. Moving from purées to more complex textures at the right time

Texture is an important part of food. There is some evidence pointing to the importance of when different textures are introduced. For example, babies aged 6 to 12 months who had experience of different textures of apple purée (for example, purée, lumps, chopped into pieces) preferred more complex textures in later testing. In addition, children aged 7 who were introduced to lumpy food only after 9 months, compared with those introduced to such food between 6 and 9 months, ate fewer different food groups, including all 10 categories of fruits and vegetables, and had significantly more problems related to eating. So food acceptance is positively affected not only by a variety of tastes and aromas, but also by a variety of textures.

5. Homemade food and commercial food

Homemade food supports better acceptance of fruits and vegetables in children, because it lets them get used to more complex textures and natural flavors. Unlike commercially prepared baby foods with a predictable, consistent taste and uniform texture, homemade dishes can have a variety of taste and texture characteristics. This helps children build a positive attitude toward healthy food. Offering foods again in different forms and textures supports gradual adjustment to new tastes and increases dietary variety in the future.

6. Limiting foods with added sugar and a high salt content in the first years of life

There is no need to add salt or sugar to your baby’s food. Despite an inborn preference for sweet and salty, frequently eating foods with added sugar or salt can strengthen this preference.

Interestingly, the inborn preference for salty taste can also be influenced by the mother’s experience during pregnancy. Studies show that babies whose mothers had severe morning sickness already show a stronger preference for salty taste at 4 months. In adolescence and adulthood, the same preference for saltier foods is found in people who had episodes of vomiting or diarrhea in early childhood, or whose mothers also had morning sickness during pregnancy.

This happens because when the body loses fluid, it also loses sodium — an important electrolyte — and to restore the balance, the physiological need for salt goes up. If such states occur during critical periods of development (for example, in the womb or in early childhood), the brain “remembers” this need, and this can form a long-term preference for salty taste.

This confirms once again: food preferences are strongly influenced by early experience, and this influence can last for many years.

In today’s food environment, where children are surrounded by large amounts of sweet, low-nutrient foods from an early age, a stronger liking for sweet and salty tastes can become an extra risk factor — in particular for developing excess weight and health problems.

It is worth noting that this limit applies specifically to foods with added sugar. There is no need to avoid or delay introducing naturally sweet foods, such as fruit or berries. Research does not support the common belief that vegetables should be introduced first so that your baby does not get used to sweet tastes. What matters more is variety in the diet and regularly offering foods again — these are the factors that influence how food preferences form the most.

7. A responsive environment and a positive example from important adults

The context in which your child gets to know new foods has a big influence on how they perceive food. Children often copy the behavior of adults, so the role model provided by parents or other people who matter to your child has a significant effect on how your baby’s food preferences form. If adults eat a varied diet, with pleasure, willingly try new things and show a healthy attitude to food, children are more likely to take on that behavior.

A responsive environment that supports healthy eating habits and offers positive examples gives your child the chance to develop their own attitude to food, based on inner motivation rather than outside pressure or rules. At the same time, pressure, bans, rewards or distraction may work for a while, but over time they contribute to picky eating, a shortfall in calories and nutrients, and increase signs of food neophobia.

Conclusion

Despite the widespread idea that food choice is purely a cultural phenomenon, convincing scientific evidence shows that it is children’s biological features that make them especially vulnerable to today’s food environment, which is rich in processed products high in salt and sugar.

Although we cannot change children’s innate leaning toward sweet and salty, or make them love cabbage more than candy, current evidence shows that early taste experience plays a key role in shaping food preferences and the relationship with food.

Through amniotic fluid and breast milk, a baby receives the first signals from the mother’s diet, so the mother’s diet during pregnancy and breastfeeding can set a healthy course for the development of taste preferences. For babies who receive formula, repeatedly offering a variety of foods becomes critically important. However, for a liking for vegetables or fruit to take hold, a child needs not just to taste them, but also to see the people close to them eating these foods regularly.

At the same time, no less important than the diet itself is the emotional context in which your baby gets to know food. A responsive, supportive environment, where food choices are not imposed through pressure, bans or rewards, helps build internal motivation.

In such an environment, a child learns to trust their body, to discover different tastes without pressure and fear, and forms a healthy, flexible relationship with food.

This skill is especially important in today’s world, where it is easy to get lost among diet rules, bright packaging and aggressive advertising of processed products.

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