3 Ways to Save Yourself and Your Wallet From Your Brain at the Grocery Store

Grocery shopping isn't exactly an exciting part of the week for most people. We go in, grab what we need, maybe pick up a chocolate bar, and get out.

It's a big part of your weekly expenses, but have you ever taken time to wonder why you buy the specific things that you buy?

As it turns out, a lot of our purchases are affected by factors completely unrelated to cold, hard preferences, which leads to a lot of impulse buying, habitual buying, and buying based on what other people are doing. These mistakes are costing us our money -- and our waistlines.

Pretty! Shiny!What brand of toothpaste do you buy? Do you have a favorite, or do you just grab whatever happens to catch your eye?

If it's the latter, you're far from alone. Next time you're shopping for toothpaste, do yourself a favor and take a step back and look at the shelf.

You'll probably see a lot of differentiation between customer groups (whitening, kiddy flavors, sensitive teeth, etc.). But you might also notice a whole lot of shiny packaging. And, barring a deep sense of personal identification with a particular dental need, which box would you normally reach for?

Would it maybe be the shiny one?

Personal care companies pay a great deal of attention to the often-arbitrary ways consumers make decisions. By exploiting our normal lack of scrutiny and our tendency to associate value with nice packages, toothpaste makers effectively get the most from our wallets.

Establish some form of criteria for your purchase decisions. One might be price: Always buy the cheapest toothpaste. Another might be effectiveness: Figure out which brand works best, and stick with it. This could work equally well for toothpaste as for breakfast cereal, another product that often comes in eye-catching packaging.

Of course, "effectiveness" comes with its own set of problems. We tend to view products that cost more or come in a nicer box more favorably, so you could get yourself into trouble here if you're not careful. Blind Lucky Charms taste tests, anyone?

What do I usually do?I don't know about you, but I buy almost the same bundle of groceries every week: same brand of milk, same bag of carrots, etc. I like to think that if the carrots looked really bad, I would skip them over, but to be honest, I don't know if I'd actually do it.

That's because habit is an extremely powerful driver of behavior.

Consider the popcorn experiment. Participants were invited to watch a movie and given either stale or fresh popcorn.

It turned out that people who often ate popcorn at the movies at the same amount, regardless of whether it was stale or fresh -- even though they reported disliking the stale popcorn! Those who didn't indulge so often ate less of the stale popcorn because, as everyone noticed, it was stale.

Habits can be wonderfully healthy or terribly self-defeating. When it comes to your grocery habits, maybe you're buying "bad" stuff out of habit, even though you objectively want to eat better. It can be extremely difficult to break such a habit once it's established.

Instead of beating yourself up for picking up frozen pizza again, make a shopping list before you leave the house. If you want to be really careful, make the list and go shopping after you've eaten so your hunger is less likely to lead you to excessive purchases. Shopping from a list frees you from the burden of decision-making and the temptation of those unhealthy but super delicious purchases, which will make it easier to build the kinds of habits you want and let go of those you don't.

What does everyone else do?Just as we tend to stick with our own habits, we have a tendency to stick to the habits of society as a whole. Social norms are a very powerful motivator to buy certain things and not others.

For example, a study on eco-friendly products found that an unexpectedly important factor in a person's decision to go green was his or her perception of the moral norm -- that is, what he or she thought was the common moral stance on eco-friendly products.

This means our own well-thought-out ethical outlook isn't necessarily as strong as the prevailing outlook around us, and that can lead us to some unnecessarily costly shopping decisions.

Morals are all well and good, of course, but they can also be exploited to make you pay more money for the same products. Take a look at the packaged food and cleaning aisles, and you'll see countless examples of "eco-friendly" products that give you a warm, fuzzy feeling at a preposterous price. Still worse, many of these aren't even really green -- they're just taking advantage of a marketing trend known to increase pricing power.

So, rethink your stance. Is the organic hand-soap really necessary, or are you buying it just to impress the odd guest at your house? If you're not sure, refrain. Even if you do find it important to be eco-friendly, do your research before picking up everything with a green package. If you can confirm which products' premium prices are justified, you can make sure you're only spending more when it makes a difference -- and this could save you an awful lot of money.

In all of these cases, it's important to remember that our decisions are not always driven by careful and logical consideration. That's OK: Even if we wanted to shop with perfect logic every trip to the store, we don't always have time for it.

But being aware of how psychology and the influence of others can lead us astray can help you save time, money, and a bit of your waistline. Well worth the effort.

The article 3 Ways to Save Yourself and Your Wallet From Your Brain at the Grocery Store originally appeared on Fool.com.

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