What canned food should you never eat?

Are canned foods unhealthy?

Table of Contents:

Are canned foods lower in nutrients?

One advantage of canned food is obvious: yours long durability makes them an ideal stash when the fridge is empty.

But is the criticism that they contain fewer nutrients correct?

No - with a few exceptions: The content of the main nutrients remains largely unchanged, heat sensitive Micronutrients like vitamin C. are dwindling, however.

But that's not as bad as it sounds, because: We get this water-soluble vitamin mainly from fresh fruit, lettuce, herbs and unheated vegetables. Not from a warm meal - whether freshly prepared or canned.

Even if fresh potatoes are rich in vitamin C, for example, the content drops significantly when cooking, frying and the like.

In addition to vitamin C, it comes with preservation - as well as with classic cooking - Loss of other micronutrients such as B vitamins and beta-carotene.

Summarized: Canned foods perform worse than raw food in terms of micronutrients, but sensitive ingredients are also lost when fresh food is prepared.

Correspondingly, a canned meal is not necessarily lower in nutrients compared to a freshly cooked meal.

Tip: Make sure that you prepare food in a nutrient-friendly way and that you expose it to as little heat as possible.

Special preserves even convince with an extra portion of nutrients, which I will present to you in the next paragraph.

Canned tomatoes - a superfood?

Fresh tomatoes are an ideal supplier of vitamin C, but canned tomatoes contain more of another nutrient.

The cell protecting ingredient lycopene which is responsible for the brilliant red color of tomatoes, comes concentrated in canned tomatoes in front.

Lycopene is an antioxidant phytochemicals that can reduce the risk of cancer by rendering free radicals harmless.

Tomato paste is therefore an excellent base for pasta sauces or soups.

Important: Despite this benefit, you should look out for BPA-free doses. More on this in the next section.

Reading tip:Preserving in the oven - that's how it works

Bad aftertaste: Can components of the can pass into the food?

Cans mainly consist of the types of sheet metal aluminum or Tinplate (thin sheet steel with chrome or tin-containing coating). Already at this position result health problems: In tin cans, acidic food - or brine containing salt - can dissolve metal components.

This creates the risk that aluminum particles, for example, get onto the contents of the can. In order to prevent transmission to the food contained, the packaging material for food is also included Epoxy plastic coated.

Another reason for the coating of the inside of the can: the metal components can come off even after years of storage and that Aroma affect the content. Additionally it can over time too Discoloration the groceries are coming.

The cause of the sensory changes and that Health risk is due to corrosion. The can material reacts with the oxygen in the environment. In some cases this can be too porous areas (leaks) and Bulges (bulges) which also pose a health risk.

Tips: I recommend you, not to buy damaged canned food with dents. Otherwise it cannot be ruled out that metal particles have migrated to the food. In addition, the contents can already be spoiled by the fact that cans with a dented, bulged lid are on the shelf. In this regard, I advise you to be extremely careful: spore-forming bacteria can lead to food poisoning (botulism).

Internal Coating Risks: BPA

The inner coating with Epoxy resin makes perfect sense for the reasons presented above. The problem with can liner, however, is that there are still numerous internal coatings BPA contain. Above all, when the cans are sterilized, this pollutant can migrate to the contents. Especially if the food is rich in fat or acid.

Unfortunately, there is currently only few alternatives for can linings containing BPA. Play it polyester and Phenolic resin a role. However, particles can also come off the new linings. It is not yet clear whether these are also of concern to our health.

It became a 2018 Maximum value - a so-called specific migration value - issued by BPA for can coatings (0.05 mg per kg of food) for the EU, but a health risk remains. A detection limit of 0.01 mg BPA per kg of food applies to baby food.

It is difficult to assess whether and how much BPA is in the food. It depends, among other things, on the acid content of the can, temperature fluctuations during storage and the fat content of the food.

Coconut milk and canned tuna followed by tomatoes are particularly endangered.

The inside of cans is often lined with epoxy resin, which can cause the toxic BPA to migrate to the contents. Photo: webandi (Pixabay)

What are the consequences of BPA for the body?

The frequent consumption of canned food contaminated with BPA, the one estrogen-like effect unfold is associated with an increased risk of numerous diseases. These include diabetes, hypertension (high blood pressure) and breast and testicular cancer. The same applies to cardiovascular diseases, obesity and functional disorders of the immune system. In addition, it is discussed to what extent BPA can cause deformities in growing children.


  • I would definitely recommend you not to buy cans outside the EU - and especially from Asia - as it is impossible to estimate the health risk posed by the canned food. Popular ingredients from the Asia shop can now also be found in the organic shop. And pay attention - as already mentioned - to the label "BPA-free".
  • You should decant the contents of the can after opening, in case anything is left over. Otherwise there is a risk that harmful substances such as tin, which is harmful to the kidneys, will loosen from the protective lacquer.

How often is canned food allowed?

I can't give you an exact tip on how much canned food you can eat per week without taking any health risks. But I recommend that you heed the tips in the next paragraph, which I adhere to myself.

I eat 1 to 2 doses per week, with canned tomatoes for pasta sauces or homemade pizza making up the largest share. Occasionally I buy chilli sin carne from a can, coconut milk or pineapple in their own juice. However, I have now also discovered the latter in a glass in my health food store - just like tomato paste. That's it already. If there is anything left over, I transfer it to another container and keep it in the refrigerator.

Buying tips for canned food

I recommend you first always prefer fresh fruit and vegetables. The purchase of canned food such as canned tomatoes or corn can occasionally supplement the fresh goods. When buying, make sure that the cans do not contain BPA (it says on the casing).

Prefer packaging Paper and cardboard. There is, for example, tomatoes or frozen herbs. The same goes for vegetables like peas or vegetable mixes that you think are fresh regional seasonal goods or should buy frozen - for example blueberries and raspberries outside of summer.

are Glasses a good alternative to cans? Unfortunately, they are not more environmentally friendly. Their transport weight is high and recycling is laborious (exception: deposit glasses). After all, there is no BPA in the jar itself - but in many lids. This is why the following also applies to glasses: Check whether the packaging says "free of BPA".

Many foods are also available in jars or you can easily preserve them yourself. Photo: Ray Shrewsberry (Pixabay)

Since the content of artificial additives such as flavors and co. In organic products is significantly lower, you should Organic quality canned food to prefer. In addition, the raw material for stews and Co. is usually more nutrient-rich, more environmentally friendly and significantly less polluted with pollutants.

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Cover picture: SevenCooks