Food-ology: the psychology of food, taste and changing eating habits
Why is it that some foods have more appeal to us, and our children, than others? Why are some foods harder to say “no” to? And why is it so hard to change our eating habits? If you have a fussy foodie or if you have been on a crusade to change your eating habits or have ever wondered why it’s so hard to change the trend of increasing waistlines, then this fact sheet is going to be right up your alley. Huggies Baby Club nutritionist Leanne Cooper takes a look at the science and the psychology behind our eating habits to help make sense of why some habits die hard, and just how they came about in the first place.
Getting to know our food preferences
The foods we like and want are influenced by a number of factors including internal ones such as genetics and your physiology (for example your taste receptors), and external factors such as your cultural background and family life.
Our life stage will also influence our food choices; at any time your current health, lifestyle, personal life and beliefs will naturally affect what you choose to eat and what you choose not to eat (and drink). The reason adults choose a certain food is generally different from a child’s. For example, adults may be influenced by health concerns, convenience and cost, whereas children are more likely to be influenced by taste experiences, visual appearance and access. The importance of these factors becomes very evident when trying to amend an eating habit, and being aware of them can affect the likelihood of success.
By understanding our food preferences we can better understand how our and our children’s eating habits are formed, as well as how to work with them.
Before we go on, lets just consider a few terms.
- Food preference itself refers to our choice of one food over another, so for example steak over chicken.
- Taste preference refers to one taste over another for example savoury foods over sweet foods.
We should also keep in mind that liking and wanting are two different things. I can like sugar but after my eighth sweet I may not want any more. It also seems that liking is easier to amend and wanting seems more deeply “ingrained” within us.
How does taste work?
Our palate seems able to detect so many subtle flavours in our food and drink, however, there are really only a few distinct taste sensations. Our taste buds can pick up, sweet, bitter, sour, salty and umami (savoury). Fat on the other hand is believed to be distinguished by its texture. Interestingly our taste buds for different tastes are in different places on our tongue.
It also appears that our acuity to taste (taste sensitivity) affects how we accept new foods. For example, it is likely that picky children who have a high taste acuity will be less likely to adjust to new foods, where as children who have a lowered taste sensitivity respond more favourably to new foods and tastes. So you can see that to some degree we are fighting nature when we try to change some eating habits. A good example comes from research in the area of food neophobia in children; studies suggest those with heightened taste sensitivity are less likely to respond to attempts to increase food acceptance by actions such as food-taste exposure.
Taste preferences start earlier than you may think
You will have heard or read that our early years are an important time for setting up healthy eating habits; but you might be surprised to learn just how early our food preferences can begin.
Recent research has shown that taste preferences develop as early as the foetal stage. Studies have demonstrated that if a mother consumes a certain food (for example carrot juice), then infants are more accepting of the food when they begin solids. The same effect occurs via breastmilk. In addition, this early exposure for baby leads to a wider array of tastes and may increase acceptance of foods down the track. So there’s even more reason to eat well while pregnant and during breastfeeding.
How do our main taste preferences come about?
- The preference for sweet is innate
It appears our only innate taste preference is for sweet and that we are designed to reject bitter tastes, some suggest that this is a survival mechanism to avoid ingesting poison. Potentially this helps to explain why many children appear to be predisposed to reject vegetables, particularly those that err on the bitter side. Do I hear a few sighs of relief out there?
I can just hear those pennies dropping. So that’s why those lovely fruit purees you offered baby went down so well, and why somehow baby knew when you were offering a vegetable and clamped his mouth tightly shut. Variety of healthy foods throughout the solids stage is very important, so keep the balance tilted towards vegies. Don’t stop offering if they are rejected; it may just be a matter of time before baby’s taste buds adapt to the more bitter foods. While sweet taste preference is one given by nature, parents still control the environment: remember “parents offer, children choose”. If you give in to the sweet tastes it gets harder to amend this; keep home for the good stuff and leave the sweet stuff for outings.
- Our great love of salt
A liking for salty (and or fatty) foods is something that we learn. It appears that newborns are not able to differentiate salty tastes, though they quickly learn this by about four months of age. Yes, just in time for solids! In fact it seems our love of salt is one of the quickest learnt preferences, so it won’t take long for them to become “hooked” on salt. Avoid using salt in children’s meals and remember most of our salt comes from processed foods (80 per cent). Children who are exposed to salt early on and repeatedly ingest it are very likely going to be adults who love their salt also.
So it’s important to keep in mind that our environment exerts considerable control over our love of salty (and fatty) foods. Don’t let the horse bolt, that’s the key! As we will see, food habits formed during early childhood appear to be the hardest to change.
The good news is that everyone can adjust to less salt and less salty tasting foods. Simply slowly reducing the salt, opting for low-salt foods and avoiding heavily salted products will quickly result in a readjustment of taste buds. Before you know it you can detect all sorts of fabulous tastes and you will baulk at an overly salted meal. A word of warning though, while reducing your salt can reduce your want for salt, you may still find that you like the stuff, making it easy to revert to old habits if you let up.
- Is fatty food comfort food?
Fat, as we will see, really is in a league of its own! Our preference for fatty foods appears to be learnt in a similar fashion to salt; however, our ability to detect and react to fat levels in food is quite different. And while we are able to adjust to a diet lower in fatty tastes, we appear to find it difficult to sustain these diets. It seems that while our taste perceptions can adjust, our want and love for fatty foods lags behind. It may take some time before our love of fat is extinguished sufficiently for us to make a permanent change in our eating habits, and for it to be one that we truly enjoy. This might explain why, after a sustained high-fat diet we find healthy food a little on the “dim” side taste-wise.
You might have heard some people saying “fat tastes good” and arguing that is why we love fatty foods so much. Well, strictly speaking this is not true, after all there wouldn’t be many of us who would say a lump of butter tastes good? It is a little more complex than that: fat gives food improved palatability, which we associate with a positive experience.
Changes to fatty food preferences need to involve a shift of enjoyment to tasty, healthful foods. Making such shifts and the decisions that go along with them are far easier said than done as it is likely we are fighting very ingrained thinking patterns.
Interestingly, it appears that our love of fatty foods is heightened when we are hungry. How many of us haven’t felt that urge for a greasy takeaway after a long day without food? Hunger is not our friend when we are trying to make good food choices!
The influence of “good tasting food”
“Palatability” sounds a simple term; logically one would assume it refers to how appealing a food or meal is. In fact it is far more complex than that. Palatability of a food relates more to the hedonic or pleasurable experience that a food or a nutrient such as fat creates within us. The level of pleasure we gain from a food will depend on many things, including your brain chemistry (specifically opioid levels), who you are eating with, the atmosphere, the reason you are eating and so on. Palatability can also be learnt and in fact it seems it can override our natural cues of hunger and satiety (fullness). This might explain why we can easily overeat indulgent foods.
Interestingly, palatability of foods is greatest when we are deprived of the food and is lowest after we have eaten it. Doesn’t that just make perfect sense of all those times when you gave in to a dessert you were craving, but afterwards you suddenly feel that the anticipation was better than the experience? Still we do this time and time again, which brings us back to liking and wanting being quite different. While you can reduce your liking of something, the wanting still remains a salient factor. Research seems to suggest that wanting is not easily down-regulated because it may be governed by processes beyond our mere physiology. Just how this works is not as yet understood, though it is likely that our higher order processes such as our emotions are involved.
Factors affecting a child’s food choices
So we know now that repeated exposure is likely to increase the acceptance of new tastes and foods; but let’s look at the effect of associations with food and the influence of role models on eating habits.
Studies show that while repeated exposure to new foods is important to early eating habits, it’s also the environment in which the exposure occurs that has an impact. A child’s initial association with a food may well affect their reaction to it next time. For example, where a food has been linked to a positive feeling such as feeling full, it may increase one’s preference for this food a little. As apposed to where a food was eaten in a negative environment or had negative consequences, for example where it was given forcefully or if it resulted in gagging; this may lead to future rejection of that food.
Children also tend to eat as we do; whether this is a consequence of social learning (also referred to as modelling) where our children copy us, or whether it is result of pure exposure, that is they eat what you eat because that’s what you have in our house, is not clear. Regardless, you can take it that eating well yourself and keeping the home for healthy foods are going to be good habits.
Changing habits and patterns
If you feel that the current stock of advertising and media messages have been ineffective at reducing our waistlines you are probably right. Research tends to suggest that reconditioning to connect healthy food with enjoyment appears more effective in creating change than mere education alone. For example, luring individuals by means of very appealing and also healthy food may be more effective at eliciting change and behavioural shifts than warnings of the health-related dangers of saturated fat.
Really, you could take a leaf out of Jamie Oliver’s books, in that it’s not just about education it’s about doing, experiencing and enjoying.
- Unlearning habits
Studies suggest in the case of where we have learnt an eating behaviour from watching others, or cognitive learning (education), that “unlearning” may be best done in the same way as the initial learning. For example, habits gained by imitation (copying) or cognitive learning (for example education) may be best changed by reasoning and cognitive information or by the example of significant role models.
- Habits hardest to change
We know that how we learn a behaviour or a food preference in the first place affects how these are then amended. However, some habits die harder than others. The hardest of all behaviours to alter are those that we learn unconsciously, as in the case of innate preferences for sweet, followed by those learnt via early learning experiences. However, these can be over-ridden more easily during “sensitive periods” in life, such as early childhood, late adolescence coinciding with independent living, major changes such as divorce or spousal death, plus pregnancy. So never, say never?
Change is easiest for things we have been taught or that we have copied from others.
Now theory is all very grand, however, applying theory to real life can be a totally different ball game! So let’s have a look at some examples and how we can apply our new knowledge.
- Example 1: Solids when baby is ready
Sofie is four and a half months old*, her mum has been trying to get her to take solids for two weeks now. However, Sofie simply closes her mouth and wiggles about and the food that does go in generally comes back out after Sofie gags on it.
Sofie may still have a strong tongue-thrust reflex, which is not only preventing her from swallowing but also causing her to gag. Unfortunately the gagging may now be an unpleasant association to solids. Don’t be tempted to start solids too early (not before 16 weeks). Start when your baby shows the relevant signals. Starting out right is more likely to result in a positive experience for you both and increase the acceptance of a variety of foods.
- Example 2: Salt
Jimmy is two and a half years old and loves his salty foods. Having a Japanese background has exposed him to an extensive array of salty foods including miso, heavily salted Japanese crackers and dad adds salt to all meals both during preparation and at the table.
So? we know Jimmy has learnt this taste preference and salt taste buds adapt quickly to levels of salt in the diet. Jimmy’s parents could simply cut out all added salt in the home and, once comfortable with this, move onto the salted products by reducing the number of times these are offered during the week and the quantity at any one time.
- Example 3: Sweet taste preference
Maya is five and loves all things sweet; in fact she has now learnt to avoid anything that has even the vaguest bitter taste in preference for starchy, fatty salty foods.
So? we know that Maya’s love of sweet things is probably not going to be something we can change easily as it is an unconsciously learnt preference. However, we can use sweet foods to encourage an increase in other tastes. It is far better to offer new foods with familiar foods (even if it is tomato sauce, salt reduced of course) and focus on what is eaten as apposed to what wasn’t, creating a positive experience around food.
Also, we need to focus on the positives not the negatives to avoid creating negative associations with foods we want Maya to eat. So dessert is offered for eating dinner. Rather than “you can’t have dessert if you don’t eat your dinner”. It may sound simple or even silly, but you will see that it has a big impact on dinner time as well as how readily Maya will eat things she usually rejects. Keep in mind that studies show a more permanent change in eating habits where rewards are not used.
- Example 4: Fatty fervour?
Charlie is 12 and loves fatty foods, he has been recommended to be more active and watch his intake of unhealthy junk foods, swapping them for fruit and vegetables.
Now, we know that the word “love” is going to play a huge role in making the switch to a healthier diet and while we can talk to Charlie till we are blue in the face about the health issues of saturated fat and even reduce his liking for fatty foods, his wanting for such foods is probably going to be working against us. Likely the process to move Charlie from a love of fatty foods will require a slow but consistent readjustment to healthier options. This may involve hands-on experience with food to increase the pleasure around food.
NOTE: It’s important to note, however, that you should never place a child on a diet; even healthcare professionals who work with overweight children do not do this. Instead, to avoid affecting their growth from limiting their intake the focus is on activity and creating a varied diet of healthy foods. Over time such children will “grow into their bodies”, slowly, and consequently their rate of growth will not be affected.
Enjoy your food, favour the fresh stuff and flavour naturally.
- Current WHO and NHMRC guidelines recommend solids at “about 6 months”. However, there is likely to be a shift toward 4-6 months (as per the readiness of the infant) for the introduction of solids. As such, this is inline with ASCIA and other agency recommendations as a consequence of recent research into delayed solids and food allergies. For more information visit www.allery.org.au.
This information has been provided by Leanne Cooper from Cadence Institute of Nutrition & Health Coaching. Leanne is a qualified nutritionist and mother of two very active boys.
Last Published* December, 2022
*Please note that the published date may not be the same as the date that the content was created and that information above may have changed since.