How the Psychology of Eating Behavior Can Help Explain Food Waste

A blog-keeping note: the national spotlight series is by no means over! I am just going to intersperse other posts, like this one, when inspiration strikes.

Recently, I read a study by Oxford’s Department of Experimental Psychology that made me reflect more on how our eating behavior leads to waste. The experiment, published in 1982, tested how variety in the color, texture, and flavor of food in a meal influenced a person’s consumption and enjoyment. Only one of the sensory properties was changed in each round of the experiment while the other two were held constant. For instance, Smarties (a candy similar to M&M’s) were used to test the influence of color because they are uniform in texture and chocolate flavor.

I won’t recap the entire process and detailed findings of the experiment, but the general conclusion was that humans eat more when offered food in varying textures, colors, or flavors. So, if given a plate of only green Smarties, we will eat fewer than if we were given a plate of mixed-color Smarties. This indicates that there is a sensory-specific satiety effect: we stop eating sooner when eating a ‘plain’ meal than when our senses are variously stimulated by a meal, even if there is no difference in the nutrition of the food to influence our actual fullness.

Another conclusion of the experiment was that “the degree of pleasantness of a food may affect whether a food will be selected for ingestion, but the amount actually ingested will then depend to a considerable extent on the satiating power of that particular food.” In other words, knowing that we like a food makes us more likely to choose to eat it but does not necessarily mean that we will eat more of it, especially if it is something filling. This is the part of the report that got me thinking about waste:

Put this effect in the context of a buffet, dining hall, or any other smorgasbord scenario where we are presented with an abundance of options. Many people erroneously start filling their plates or trays before having seen all of the available foods. When they then come across a favorite food of theirs, they add a large portion of that to their meal because they know they are going to enjoy it. They don’t generally think about how much other food they already have; they prioritize the favorite and end up with an extra large portion.

buffetAssuming they recognize their satiety (which is often difficult to do, leading to overeating), the eaters will not finish all of the food that they have taken. Whether the diners scarfed down their favorite food first or tried to save the best for last, some remnants of the superportion will be left. Of course, leftovers can be given to a friend or taken home in a doggy-bag, yet the sad truth of the matter is that many people leave the food to be thrown out. I don’t have any statistics to back it up, but I believe that people are more likely to bring home leftovers from a meal paid for a la carte than in a buffet-type setting because they feel more motivated to get their money’s worth. In restaurants, you think, “I spent $12 on that pizza, so those last three slices are $4!” When you pay a flat rate for a self-serve meal, though, you pay for ‘all you can eat,’ which is achieved once you are full.

It’s no surprise that presenting people with an abundance of food, especially food they know they like, can easily lead to waste. Nor is it shocking to read that our eating behavior is influenced by psychological at least as much as by physiological and nutritional factors. Still, the study makes an interesting read to explain the extent of this influence and reflect on its role in issues like food waste or obesity.


Pleasure Study of Food

Screen Shot 2014-11-12 at 10.56.30 AMEver noticed how the first spring roll seems to taste better than the other five? Or how a fun-sized Halloween candy bar is more satisfying than the regular one? This feeling isn’t necessarily because your stomach is telling you that you’re getting full; rather, it’s your senses becoming accustomed to the flavor. Boredom with flavor is a real sensory phenomenon that develops as you consume food over a period of time. The food is still yummy, but its taste-novelty wears off with every bite, exciting your senses less and less.

A study by Novakova et al. investigated how smell influenced people’s enjoyment of food while eating. Participants were asked to look at, sniff, and chew (taking ten seconds for each ‘step’) ten individual banana slices and then rate their satisfaction on a 21-point scale. Half of the thirty participants had congenital anosmia (loss of smell), while the rest could smell normally. Since taste and smell are intertwined, the idea behind removing the aroma factor was to isolate the food’s flavor and its pleasure effects. Quick semantic note: taste is the way your body interprets a food’s objective flavor.

As expected, the control (‘normal’) group demonstrated a clear decrease in enjoyment as participants made their way through the ten slices. More noteworthy was the fact that the anosmic group continuously gave higher satisfaction ratings than the control group. Not only did they rate that the food tasted better initially, but their pleasure ratings waned to a lesser degree than those of the control. One proposed reason for this is that the absence of the smell lessened the overall habituation effect that normally causes loss of flavor appreciation. Another possibility is that, much like how blind people tend to have better hearing, anosmics have a more receptive palate. In any case, the study shows how our senses influence our perception of flavor and dull to its enjoyment as we eat.

Screen Shot 2014-11-12 at 10.57.29 AMWhile the effect of prolonged sensory stimulation is really interesting in itself, recognizing it could also be helpful in preventing food waste. For instance, when many people say that they’re ‘full’ from a dish, they mean, “I have satisfied myself with this taste,” rather than, “My stomach has been filled.” They might even proceed to another course, typically dessert, to provide their senses with new delights. This becomes a problem if the initial meal wasn’t finished and its leftovers aren’t saved: food is wasted simply because the eater got bored. However, people who frequently find themselves in this situation can easily resolve it. If, for whatever reason, saving leftovers isn’t an option, simply take less food to begin with. Other options are to share with friends or assemble a diverse plate, full of small portions of unique flavors that will, hopefully, encourage you to finish what you have.

Cherish your food and relish the experience of eating it.


The Sour side of Sweet

Everyone knows that a piece of chocolate can help you boost your mood when things are looking gloomy, but don’t bring refined sugars into this circle. The British Journal of Psychiatry published a cross-cultural analysis in 2011 that showed a ‘strong correlation between refined sugar consumption and mental illness’.

“What could cause this?’, you maybe asking yourself. Well, we have got the breakdown, it involves some neurological terms, but bare with us, it’s important. What you need to understand is that our brain requires a chemical called ‘brain-derived neurotrophic factor‘ (BDNF) which serves as a growth hormone in the brain. It helps maintain the health of the millions of neurons working in our brain muscle by helping them make new connections between each other and aid with memory function.

Refined sugar consumption suppresses the release of this hormone, which has a potential to increase depression and schizophrenia. In fact, individuals that suffered from these mental illnesses, were shown to have low levels of the BDNF hormone.  Aside from causing a risk for mental illnesses, consuming high dosage of refined sugar leads to inflammation in the body and prevents our immune system from properly functioning. This chronic inflammation can lead to arthritis, different forms of cancer, diabetes, heart diseases, and other illnesses, which includes depression and schizophrenia.

Professor of University of Kansas, Dr. Illardi, said that there is a solution for this, and all it requires of you is a diet change. His patients, suffering from mental illnesses, have shown that their new diet high in whole grains and low in refined foods and sugar, significantly improved their mental health and clarity. So the next time you are having a bad day, remember to stick to natural sugars and chocolates, and leave those refined sugars and food to the side, they will only worsen your mental state.

New Hunger Report

Generations United published their recent report on Hunger in America. Filled with interesting statistics and visuals, the report hopes to shed light on the growing problem of hunger that millions of Americans face on a daily basis.

Staggering statistics show that “1 in 5 children are hungry, or at risk of hunger” in one of the wealthiest countries in the world. This begs the questions of: “How is this possible?” and “Why isn’t something being done to end this?”

Instead, the current talks of a fiscal cliff in the US government puts programs such as Supplemental Nutrition Assistance Program (SNAP) under threat of budget cuts. This would leave 3 million of hungry Americans facing this problem all on their own.

Review of 2012 food trends

The Food Nutrition & Science magazine, predicted that 2012 will be the year more dads stay at home and prepare meals. That farmers will become food celebrities and our phones will be used to check out at the local supermarkets.

A more realistic prediction was that people will become more aware about the high volume of food we discard on a daily basis. And that ethnic food will become more popular, as food trucks emerge as a common trend around the city streets.

Another big question on the table was the differentiation between  ‘good’ vs. ‘bad’ fats. The answer, of course, depends on our ability to self control and eat in right proportions. To review all these 10 food trend predictions for the year 2012 and make some of your own predictions for 2013, click on the link here.