Ever hear of the endowment effect? In its simplest terms, this refers to the added worth that humans give to things that they own. Studies have shown, for example, that people will sell a product they own for a much higher price than they'd be willing to pay for it when buying from someone else. Can you relate? It sounds like fairly predictable human behavior. But to what extremes can this endowment effect influence our eating habits? This is where it gets interesting.
Lauren Block, a marketing professor at Baruch College in New York City, is co-authoring a study to be published in the June issue of the Journal of Consumer Research. In this study, she and her team questioned 165 students about their yogurt preferences. The students were given yogurt smoothies that were past their "best if enjoyed by" date, although they were still considered safe to eat. The students were split into two groups. The "endowed" group of students, were told the yogurt was theirs to keep.
The results of these findings showed that 38% of those in the endowed group were willing to drink the smoothie either right then or later. But only 13 percent of the students who didn't own the yogurt were willing to drink the smoothies. Those who were told to keep their smoothie were also less likely to think it would make them sick.
"Our results help explain why a person might consume expired food that they found in the fridge, but not consume expired food found in a friend's fridge," Block said. This endowment effect theory suggests that people will rationalize their behavior towards expired foods when they “own” the food.
Let’s personalize this a little. If you were in a grocery store, would you buy yogurt that you knowingly understood to be a few days past the expiry date? Probably not. But, if you looked in your fridge for that yogurt and found it was just a few days past the expiry date, you’d probably still eat it, right? This research suggests that you would (feel free to defend your own position in the comments below). Researchers chalk this up to the fact that people unconsciously give more value to things that they own, and will rationalize accordingly.
So, what’s the big deal? It’s part of the human psyche to personalize things. If we name something, we own it. If we buy it, we own it. But like it or not, possessions influence behavior. The problems start when that influence becomes negative, or irrational. This latest study raises new concerns for the health and safety of consumers who ignore expiry dates. Yogurt is one thing, but meat products are another.
Some food have inherent safety guards in place, like foods that grow moldy. If a food’s appearance or smell repels us, we probably won’t eat it (regardless of whether or not we own it). But if we follow this endowment effect theory all the way through, what about other products with expiry dates? According to Block, “Many consumers do not know that sunscreen, condoms, fire extinguishers and medicine lose efficacy over time… Our research suggests that consumers may underestimate the risk associated with using products past their expiration dates, and for some products, this might have a negative consequence."
Via: USnews.com
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I daresay experation dates would also carry more weight if they were accurate and meaningful.
Many products have best buy dates that are unusually conservative as a means to protect the producer. For example, eggs are usually still good to eat for many days past their date. Best by, use by, and sell by have distinct meaning that seldom are used correctly on packaging.
Also, I might not buy a product I would consume. I'll eat day over yogurt in my fridge because I have it and no other options (other than throw it out and take the fiscal loss), I won't buy it, however, because it might go really bad before I get arround to eating it during the week. Also, the store likely has fresher options, which given the choice and the fact that the loss is the store's, means that I will take the fresher, better choice.
Finally, most producers have now taken on the habbit of putting best by dates on a whole host of non-perishable products creating a "boy who cried wolf" syndrom to such dates. While these dates are useful to make sure that product is being rotated (not just new stuff put in front of old forever), it does nothing for people confidence in such dates. Is purified water in a container that takes thousands of years to decay really a health risk after two years? Five year old Mountain Dew still tastes good and is still carbonated. Probably would still be good in twenty years (consider that my inflation shelter). While some vitamins break down over times as short as a few months, most last for years, so your Honey Nuy Cherios will still be good for you and delicious ten years after the apocalypse . . . just don't try to milk the five headed winged cow, use powdered milk; it will still be good as well.
I only speak for myself in saying that it's not necessarily the ownership property of the item, it's that I KNOW what that item has been through, where it's been, and what's been done to it - at least in my posession. If I know that I've kept my milk sealed in my refrigerator at a frosty temperature (barely above freezing!), I will not hesitate to use that milk after its expiration date, within reason of course! This is not the case with most of my friends items or items in a restaurant. It's the same reason I try to buy things new...used items have a history you know nothing about!
I had to create an account to post this. This has nothing to do with endowment effect. There are two reasons that I would eat expired food
1. I paid for it
2. nothing else in the cupboard to eat
If you gave me a case of expired yogurt, I would probably eat it since it was free, but not because I own it.
It makes perfect sense. How does this rationale extend into our daily lives? Does this make us less wasteful if we have ownership? Such as a person who has ownership in a neighborhood will take care of the property as opposed to a renter?
Sounds like these so called scientists don't know anything about correlation studies. Where does any evidence suggest that this effect has to do with ownership?
Would you buy something that is past the sell-by date? No. Why? Because its probably gonna sit in your fridge for a few more weeks and by the time you get to eating it, it will have turned.
If I was in a store, buying something to eat for lunch right then, I would buy a yogurt expired by a few days -- we all know those expiration dates are just a guide and that the food isn't necessarily bad.
This article is just riddled with terrible science.
usually i like to open up my expired milk and do the old smell check before i drink it. If i could do that at the grocery store it might make me more prone to buying expired products lol
I would imagine that when stores price discount products that are closer to their best before date that they would sell quickly. But given the choice between identically priced products, and a longer shelf life with one. Utility maximization will occur (you chose the one with the most "value"). Same with products in the fridge, you choose to maximize your utility - eat the one a few days past, or go to the store and get another and throw out this one. If its nasty you throw it out because being sick outweighs the going to the store.
The endowment effect may be true but I don't think it works with food. In fact I seem to be more attracted to food that isn't mine - the other person's plate always looks tastier. I think we tend to enjoy the things that we know we can't eat all the time more than the things we own and can eat whenever we want.