What Expiration Dates Really Mean

Expiration dates often have nothing to do with food safety. Here's what you really need to know.


By Zoey Garcia


Have you ever gone through your refrigerator or pantry and come across a package that is well past its expiration date? Or, maybe you have read the nutritional facts at the store before buying a product and stumbled across different dates on the package that leave you in a state of confusion. This article will explain exactly what expiration date is and how you can tell if your favorite product is still safe to consume.

By definition, the expiration date is the date after which a product experiences an expected decline in quality but it does not dictate how safe the product is for consumption. It is interesting to note that the different dates printed on food containers telling us when to purchase, eat, or throw out food are actually determined by each individual manufacturer. With this being said, some foods may still be edible for anywhere between a week and a couple months longer than the date listed.

According to a study conducted by Harvard Law School’s Food Law and Policy Clinic and the Natural Resources Defense Council, more than 90% of Americans prematurely waste food that has not actually gone bad due to misinterpreting food labels.

What Exactly is an Expiration Date?

The actual term “expiration date” refers to the last date a food should be eaten or used in any way without risking illness. In fact, in America, the only items required by federal law to be labeled for expiration are infant formulas and some baby foods. Some states require pulling certain foods, such as dairy products, from the shelves on or before the expiration date to eliminate any risk.

There is actually no federal mandate that uniformly outlines expiration dates, which means that states generally use different techniques and labels to describe the shelf life of a certain product.

The term “shelf life” refers to non-perishable foods that can be stored safely on the ‘shelf’ in a pantry for a long period of time without affecting the contents of the package. Essentially, the process of canning foods is a means of preserving food by vacuum-sealing containers to make them airtight, which destroys microorganisms and deactivates certain enzymes.

A few decades ago, people began producing less and less of the foods they ate and began shopping at grocery stores, as opposed to canning their own food. In the 1970’s, food dating emerged out of the consumer demand for information on how food was made. Historically, the expiration date indicates freshness and is merely used by manufacturers to show when the product is at its peak, but does not inherently mean the food is inedible.

How to Determine if a Product is Still Edible

Unless a food product actually goes bad, how do you know if it is safe to eat? As a rule of thumb, food safety is not an issue in products that are kept on the shelf or even in the pantry for long periods of time. Canned food, specifically, has a shelf life of around two years past the expiration date, considering that it has been stored in a safe and temperature controlled environment.

On the same note, other types of packaged foods may be prone to going bad due to temperature sensitivity.

Milk should remain fresh 5 to 7 days past its expiration date. Some products may last longer, eggs can last 3 to 5 weeks beyond its expiration date. The most important thing to consider when inspecting food is using your senses to determine the condition of the contents as well as basic food safety regulations.

There are certain things to consider about the packaging of food and its condition before cracking it open to consume. Once a package is opened, it needs to be used immediately or stored in an airtight container in a refrigerator for a short period of time.

The most important aspect to consider when inspecting food that is past its expiration date is the condition of the packaging before it has been opened. Even if a can has dents or even minor damage, it does not render the food inedible. Foods that are unsafe to eat may show the following signs:

Broken seal

Can or lid is bulging due to pressure or spoiled contents

Discoloration of contents seen through packaging

Hissing and spurting upon opening

Leaking fluid or food contents

Rust or corrosion on the can

Signs of mold

Strong odors

Making Sense of Expiration Dates

You may have even noticed that there are other dates listed on package labels besides the expiration date that are an indicator of food freshness. These dates, also known as the “use by”, “sell by” date, and other packaging codes are used by manufacturers and may include a month, day, and year, but are of no significant importance to consumers.

Having a firm understanding of manufacturers packaging dates and expiration dates can help cut back on food waste as well as save you money in the long run.

Zoey is a part-time blogger and a full-time nurse. She is the founder and editor of an avenue for sharing her passion about juicing, plant-based diet and living a healthier lifestyle.

Main Photo Credit: Minerva Studio/; Second Photo Credit: allensima/; Third Photo Credit: Lisa S./; Fourth Photo Credit: Matej Kastelic/

Dec 2, 2017