Is Eating Expired Foods Dangerous?

We are going to show you which products can be consumed even when expired and when exceeding this date poses a health risk.

Written and verified by el nutricionista Saúl Sánchez.

Last update: 21 June, 2023

The consumption of expired foods is something really common in many homes. The truth is that sometimes this practice can carry a microbiological risk, leading to intoxication. Every day, someone who has eaten a product in poor condition goes to the emergency room.

However, it’s also possible that the food can be consumed after the date proposed on the packaging expires. In this case, we’re speaking of a preferred consumption date, with a different connotation than the expiration date of the product in question.

The differences between the preferred consumption date and the expiration date

From an industrial point of view, food can be classified into perishable and non-perishable. The main difference is that the former are susceptible to harboring the growth of pathogenic microorganisms. The ingestion of these could harm the state of health leading to an infection or poisoning.

On the other hand, the preferred consumption date, or “best before” date, refers to the moment from which the product loses part of its organoleptic characteristics. There’s no risk from the microbial point of view, but the flavors, odors, aromas, and texture of the product can be altered. This makes it less palatable.

Most of the ultra-processed foods of industrial origin have a best-before date, so they never expire as such. To achieve this, additives such as preservatives are added, which effectively limit the growth of bacteria. However, some of them, such as nitrites, are dangerous to health, according to a study published in Nutrients.

Despite being considered safe in the short term, the regular presence of this type of food in the diet is considered counterproductive as time progresses. They tend to contain high amounts of trans or hydrogenated fats, in addition to the aforementioned additives. There’s evidence that indicates that this type of lipid increases the risk of developing chronic and complex diseases.

At the same time, it’s possible to find perishable foods, such as meat and fish, which do have an expiration date. From the moment marked on the label, the risk of bacterial overgrowth increases, so the product is no longer safe for health.

What foods can be expired?

Not all foods have the ability to expire as such. Some simply stop being good from the point of view of taste or texture, but despite these details, they can be ingested without major complications. It’s important to know how to distinguish those that have a microbiological risk to avoid exceeding the dates set.

As a general rule, all fresh foods from animals can be expired. When meat and fish are marketed cut, there’s usually no reference to the expiration date itself, although it does exist. This usually doesn’t exceed 3-4 days after purchase. However, the product tends to get rancid beforehand, so its external appearance also worsens.

An exception must be made regarding those foods derived from animals. Eggs have an expiration date on the outside, but they really are foods that don’t spoil if they’re kept in the right conditions. The same happens with yogurts, products that last much longer than what’s on the package.

Milk, when it has been treated by means of a thermal process, is able to resist for a long time without suffering alterations. Now, it’s important not to open the container, otherwise, it’ll have to be consumed within a few days, always keeping it refrigerated.

As far as packaged meat and fish are concerned, there’s also an expiration date, but this is usually longer. In the same way that it happens with ultra-processed products, they can contain preservative additives inside, which lengthens their useful life. Sometimes they’re simply packaged in a modified atmosphere that limits microbial growth by altering the concentration of gases.

Good storage practices to prevent food from expiring prematurely

Despite the dates reflected on the fresh food packaging, it’s important to follow good hygienic practices when it comes to conservation and handling. Otherwise, they could reach expiration before the marked day. This is because the industry calculations are developed based on models that imply good practices from a hygienic point of view.

For example, if a piece of meat is left at room temperature, it will take a few hours for it to go bad. The same thing happens with fish. This occurs because the cold delays and slows the growth of pathogenic microbes. However, temperatures close to those of the human body favor its development and multiplication.

This is one of the reasons why you have to be very careful with raw egg preparations in summer. Higher temperatures can cause easy growth of Salmonella.

This bacterium is pathogenic for humans and its consumption generates gastrointestinal problems. This is evidenced by a study published in the International Journal of Environmental Research and Public Health.

To avoid unpleasant situations, it’s always best to keep perishable food in the refrigerator, and away from sunlight. Another useful option is freezing. Under low temperatures, many of the pathogenic bacteria are inactivated or destroyed, so the shelf life of the product is significantly lengthened.

It’s true that the freezing process can reduce the organoleptic characteristics of some foods. However, safety is gained from a hygienic point of view. If you buy a large quantity of food that’s not going to be eaten soon, the best option is to store it in suitable bags and freeze it.

Can moldy foods be eaten?

On some occasions, certain products can develop surface mold before the expiration date is reached. It’s something relatively common in cheeses and even vegetables and fruits. The truth is that it’s best to discard the affected part, but you can consume the rest without major problems.

Normally, these fungi aren’t pathogenic, so they don’t have the ability to infect the gastrointestinal tract and generate internal changes. Just the same, there are exceptions. Some microorganisms are capable of generating mycotoxins, substances with the power to cause severe damage.

As a general rule, mold on cheeses doesn’t cause too many problems. The part that looks bad is removed and the rest can be consumed. The mold that develops on fruits is usually more problematic, especially when they’re kept at room temperature. The best thing to do when in doubt is to throw away the food, thus avoiding possible problems.

In addition, it may be the case that some fresh foods that are marketed packaged develop a certain mold inside. This occurs due to the fact that the seal isn’t hermetic, or that good hygiene standards weren’t observed during the handling of the product. In this case, it’s important to avoid its consumption.

Is food that exceeds the “best before” date expired?

As we discussed earlier, foods that have a preferred consumption date on the outside don’t expire as such. Not even if the marked day is exceeded. It’s possible to open and consume the product with peace of mind. The worst that can happen is that the proteins are rancid or that the organoleptic characteristics have been damaged.

Now, this doesn’t mean that this class of foods can’t be expired under any circumstances. If they’re opened and kept for too many days, they can reach a state of contamination with microorganisms. In this case, their consumption would be considered dangerous and harmful to health.

The most typical example is that of packaged tomato sauces. Many times, these products are opened and the entire bottle isn’t consumed. It’s stored in the fridge and stays in this state, even without closing the lid, for quite some time. By the time the food is eaten again, there’s already significant microbial growth that causes health problems.

In this type of case, the most common is contamination with Clostridium botulinum, especially when it comes to preserves. This bacterium generates a toxin that has a paralyzing power. This is stated in an article published in the journal Epidemiologie, Mikrobiologie, Imunolige.

Of course, when there’s an overgrowth of the bacterium Clostridium botulinum inside a preserve, the smell of it is usually altered significantly. Normally, the food takes on a strange and unpleasant aroma. In these cases, the product should be discarded. If you’re in doubt about how long an open jar has been in the fridge, it’s also best to throw it away.

When making homemade sauces and preserves, it’s essential to properly sterilize the jars in which the result is to be introduced. It’s also convenient to generate a vacuum inside them. The lack of oxygen limits the growth of many microorganisms, especially the aerobic ones. They need this element to survive and reproduce.

The 6 foods you can eat even if they’re expired

Now we’re going to tell you which are the 6 foods that you can eat even if the expiration date has expired. In any case, many of them will present on their label a preferred consumption date, which, as we’ve said, is indicative.

Yogurts

Yogurts stand the test of time well if they’re kept refrigerated. They contain bacteria inside, but these aren’t pathogenic. On the contrary, they’re considered beneficial for health. In fact, they’re identified as probiotics. Its regular intake manages to exert positive effects on the body, according to a study published in Nutrients.

Bread

Sliced bread begins to go bad when mold develops inside, but this phenomenon can occur well beyond the date marked on the package. It’s one of the foods that can be consumed expired.

Of course, once green formations are observed, it’s best to discard the product. In the case of products made with flour, it’s not recommended to just remove the affected part.

Nuts

Nuts don’t really expire. They may lose quality from the organoleptic point of view, but they never experience bacterial growth inside. This is because microorganisms require a minimum percentage of water to grow. Nuts don’t meet this premise, so they’re not an optimal reservoir.

Sugary soft drinks can be consumed expired

According to research published in the journal Nutrients, these kinds of drinks aren’t recommended for health in the medium term. They have added sugars and additives capable of generating metabolic problems. However, they don’t pose a microbiological risk. They can be consumed beyond the day marked on the package without problems.

Jams

One of the classic preservatives used by the industry is sugar. It acts in a way similar to salt, limiting the growth of pathogenic bacteria. For this reason, the consumption of expired jams doesn’t carry health risks. The percentage of sugars present in their interior makes them safe products from the point of view of microbes.

Sausages

Sausages are made from meat, a theoretically perishable product with a microbiological risk. However, they have a previous curing process, in addition to large amounts of salt and additives. All these elements allow their hygiene level safety, so they don’t expire. In fact, their flavor can improve in some cases over time.

Some food can be eaten even if it’s expired

There are foods that can be consumed even if they’re expired. However, with others, you have to be extremely careful. Even without the expiration of the packaging date, problems can arise, especially if good handling or conservation practices aren’t observed.

When in doubt, it’s always better to avoid eating food. Otherwise, you can experience really harmful poisoning for your health. These scenarios are extremely dangerous for risk groups, such as the elderly and pregnant women. They carry a great risk of dehydration and digestive problems and sometimes hospital intervention is required.