Before I dig into this topic, let me just put this out there: Expiration dates are important and you should always consider them so you don't get food poisoning and end up in the hospital or whatever. Please don't interpret this post as my arguing that expiration dates are total bull.

That being said, expiration dates are total bull. Just kidding! Well, kind of. I recently came across an alarming study from Harvard, which found that Americans waste 160 billion tons [Editor's Note: Kristin pointed out that she should have written 160 billion pounds] of food annually. A similar 2012 study from the NRDC calculated that waste in terms of dollars: We throw out about $165 billion worth of food and beverages each year. On average, that's between $275 and $400 per household.

The Dating Game

The Harvard Food Law and Policy Clinic titled their study “The Dating Game,” and they came to the conclusion that many “sell by” dates don't really have anything to do with safety. Companies mostly determine those dates based on taste tests.

Emily Broad Leib, who authored the study, told CBS, “The dates are undefined in law and have nothing to do with safety. They are just a manufacturer suggestion of peak quality.”

But of course, food does go bad. Despite the liberal expiration date on that cup of Dannon in the back of your fridge, you probably shouldn't eat it if it's been there since the '90s. Okay, you definitely shouldn't eat it if it's been there since the '90s.

But Leib urges consumers to be aware that when manufacturers determine expiration dates, they're mostly thinking about protecting their brand rather than public safety. The purpose of the Harvard study was to push for a more reliable labeling system for food.

“Make an Assessment”

Until the system changes, what's the solution? Are we supposed to simply turn a blind eye to expiration dates and pray against food poisoning?

Well, of course not. Here's Leib's suggestion:

“Consumers need to take that extra minute to actually look at their food and smell their food and make an assessment. When we just rely on these dates and throw everything away after the date, we're leading to really high rates of food waste.”

Sounds like good ol' common sense, but her study found that 90 percent of households throw out food that's still perfectly good, thanks to inaccurate expiration dates.

Growing up, we always “made an assessment.” We were poor (I think I may have mentioned that once or twice?), so my mom didn't just toss out food willy-nilly. She was very discerning; but if it didn't emanate any strange odors and hadn't changed color, we usually ate it. When she did have to throw something out — when it was, say, taken over by mold — she would still shake her head and mumble, “What a waste.”

On the other hand, I'd argue that my extended family goes a little overboard. My aunt, for example, once fed us cooked rice that she neglected to tell us had been sitting out for a few days. The aftermath was not pretty.

I use the “sell by” (or, the more charming “enjoy by”) date as an approximation. If the expiration date is really, really old, I'll toss it, even if the item still looks and smells edible. If you've ever had crippling food poisoning that's left you vomiting next to your boss in the middle of a work meeting, you know it's just not worth the risk. However, if it's at least somewhat close to the expiration date, I make an assessment, and, if it still looks and smells edible, I usually go for it. Although, I tend to be stricter when it comes to meat, milk or eggs.

How Long Does Food Really Last?

When it comes to assessing “expired” food, it's probably better to rely on data rather than instinct. Ever heard of Eatbydate.com? I hadn't, until I started researching this story. It's a pretty cool website that seeks to answer the question, “How long does food really last?” It's pretty extensive, and you can check it out yourself, but here are a few items I found interesting:

When properly stored,

• Fresh whole mushrooms last 7-10 days.
• An opened pack of cream cheese lasts 1-2 weeks (stored at or below 40° F)
• Opened shredded cheese lasts 3-4 weeks (stored at or below 40° F)

The site also gives tips on how to tell if certain foods are spoiled. Their content is based on research from resources including the Department of Agriculture and the FDA.

Earlier this year, Get Rich Slowly staff writer Lisa Aberle wrote an article on food waste in general, and she pointed out some helpful ways that she avoids waste. In addition to the whole expiration date conversation, there are a couple of practical tactics I'd like to add:

Extend the Shelf Life of Your Food

I know how I make the most out of my food's shelf life, but I'm no expert, so I thought I'd check with one. Jill Houk is a food consultant and cookbook author who was kind enough to offer a few tips:

• “Don't wash fruits or vegetables before storing them,” Houk says. “Even small amounts of water can start the molding/decomposition process.”
• She adds that keeping your refrigerator temperature between 34ºF and 38ºF will help slow the bacteria growth that leads to food spoilage.
• Most of us know to store our canned goods and jarred food in a cool, dry place. But Houk warns: “Even avoid storing food too closely to your dishwasher, toaster, or coffee maker. If food experiences wild temperature fluctuations, it's more likely to spoil faster, even if it's shelf-stable.”

Meal Planning

It's easy for me, because I only live with one other person, but I try to plan out my meals and groceries for the week. I cook about four or five times a week, and, as we near the end of the week, I take an inventory of what's left over, and I try to make the most of whatever that is. If I have half an onion or a few potatoes left, I see if I can make a stew or something. Online meal planners like $5 Meal Plan are especially helpful. You type in whatever ingredients you have in your pantry, and they'll pull up recipes that include those ingredients. I don't want to sound like a commercial, but ever since I've started using their app, I find I throw out very little food.

Anyway, I'd like to know — how closely do you follow your expiration dates, and what do you think of them? Do they contribute to waste, or should we follow them strictly?