Canned foods have a reputation for having less nutritional value than fresh or even frozen foods. It has also been claimed that canned food is harmful and shouldn’t be eaten. Let’s take a closer look.
How Does Canning Food Affect Nutrients?
The process of canning food can preserve its nutritional value rather than diminishing them as some people think.
Nutrients like fats, protein and carbohydrates remain the same before and after canning while the majority of fat-soluble vitamins such as A, D, E and K as well as most minerals are preserved.
The canning process can help to increase some vitamins, like in corn or tomatoes which become richer in antioxidants when heated (1).
On the other hand vitamins like B and C can be damaged because they are vulnerable to the heat that is involved in canning.
Therefore canning does have very similar levels of vitamins, minerals and nutrients compared to fresh or frozen food and has the benefit of being preserved for longer periods of time.
Is Canned Food High In Sugar, Salt And Preservatives?
As with all processed foods, some companies will add extra salt, sugar or preservatives in during the process.
Varieties of natural or chemical preservatives can be added however this is to preserve the look, texture or color of the food because canning in itself will prolong the foods shelf life.
Some canned foods can be high in added sugar which is known to have adverse health effects.
Canned food might also contain extra salt. Salt should be consumed in moderation and can cause health risks especially in people suffering from high blood pressure
Do Canned Foods Contain BPA?
Bisphenol-A known as BPA is a chemical used for packaging food and is used in cans. Bpa has detrimental effects on the human body.
Studies have shown that the BPA in those cans does leach from the lining, into the foods. They can then be absorbed into the body.
This study assessed 78 types of canned foods and found the chemical BPA in over 90% of the sample size.
Other studies have found that eating canned food is probably the main source of BPA exposure (7).
This study focused on individuals who ate 1 serve of canned soup for 5 days. It resulted in a 1000% increase in BPA in their urine. This study in particular links BPA excretion in urine to increased risk to diabetes and cardiovascular diseases
Not all cans use BPA so it is a good idea to shop around and chose BPA free options wherever possible.
Canned Food And Deadly Bacteria
There is a deadly bacteria called Botulism or Clostridium botulinum that can be found in canned foods which have not been processed properly.
This is very rare but will cause illness or death when consumed and not treated. Botulism is more risky when you are canning at home rather than from commercially produced foods. Always avoid cans that are bulging, leaking, or have cracks or dents.
How Do You Know if the Canned Food Is Healthy?
Canned foods are not all the same, as with any processed food – there are some superstars, mediocre brands and some foods which are just plain bad for you.
The best way to distinguish between them is to read the label and study the ingredient list. Ingredient lists starting with added sugar or syrup should be avoided.
Instead choose fruits canned in water or natural juices. You will also see if extra salt or preservatives have been added.
If you are trying to reduce your salt intake – be sure to opt for either the ‘no added salt’ or try the ‘low sodium’ canned goods out there.
You can also drain and then rinse the canned food which will reduce any residual sugar or salt in the syrup or brine.
There are plenty of canned foods on the market that don’t have any additional ingredients and these are the healthiest options. Make sure you read that ingredient list to be sure.
Should We Eat Canned Food As A Part of a Balanced Diet?
Short Answer – if you can avoid them then do so. The macronutrients remain intact but some of the micronutrients are lost.
Fresh, unprocessed food is always going to be the most nutritious option however canned foods are helpful as an alternative and they have the bonus of having a much longer shelf life than fresh produce. This makes them cheaper, highly transportable and convenient.
Keep in mind that some canned foods use BPA linings which can leach into food. This will cause health issues over time. As mentioned read the labels and choose the healthiest options.