Diet and nutrition experts have been telling people for a long time not to eat too much processed food.
Some of the things the World Cancer Research Fund says we can do to prevent cancer are to eat less red and processed meat.
But the term “ultra-processed food” has only been around for a few years but is now being used more and more to describe a certain type of food. The majority of the calories that the average person in the UK consumes come from highly processed foods, according to a study released in 2018.
The level of processing that foods go through varies hugely. Food processing includes everyday tasks like making homemade bread and pasteurizing milk. Chopping and boiling are also examples of processes. But these are rarely considered unhealthy.
When talking about the commercial and industrial production of food, the phrase “processed food” is often used. This is also where the phrase “ultra-processed food” has become more common.
Tuna is one of the most popular and frequently consumed types of fish worldwide. This versatile and lean protein can be found fresh, frozen, or most commonly, canned. But the canning process leads to an important question – does tuna in a can count as processed meat?
This article will dive into how tuna is handled and packaged, how it compares nutritionally to other proteins, and whether experts classify canned tuna as a processed food.
Understanding How Tuna is Processed
Tuna destined for the canned food aisle undergoes a multi-step process
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Tuna is caught and transported to processing plants shortly after being caught.
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The fish is precooked through steam to denature proteins and soften the flesh
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After cooking, tuna is cleaned by removing inedible parts, bones, skin, and blood.
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The tuna loins are then cooled, packaged into cans, sealed, and heat sterilized.
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Finally, broth, water, oil or other flavorings are added before the can is sealed and distributed.
So while fresh tuna is simply the raw flesh of the fish, canned tuna is cooked, sterilized, and packaged with various added ingredients to preserve and enhance the flavor.
How Does Canning Affect Tuna’s Nutritional Value?
Canning makes tuna more convenient and extends its shelf life. But does it change the nutritional properties that make tuna a healthy protein choice?
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Protein: Canned tuna provides about 25g protein per 3oz serving, identical to fresh tuna. Canning does not degrade the protein quality.
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Mercury: Mercury levels remain unchanged through canning. Pregnant women and young children should still limit intake.
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Omega-3s: The beneficial omega-3 fatty acids in tuna are retained through the gentle steam cooking process.
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Vitamin D: Canning results in modest vitamin D losses, but tuna still provides this essential, hard to find vitamin.
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Sodium: Salt is added during canning, raising sodium content significantly compared to fresh. Check labels and rinse to reduce sodium.
So while some nutrients like vitamin D decrease slightly, the core benefits of tuna like protein, mercury risks, and omega-3s are unaltered by canning.
How Does Canned Tuna Compare to Other Processed Meats?
Next, let’s see how canned tuna stacks up against popular processed meats like hot dogs, bacon, and deli meats:
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Added ingredients: Tuna contains fewer chemical preservatives and artificial ingredients than hot dogs and bacon.
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Sodium: Fresh tuna is very low in sodium. Canned tuna contains added salt but much less than typical deli meats.
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Nitrates/nitrites: These carcinogenic compounds used to cure meats are not present in canned tuna.
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Cholesterol: Tuna is naturally low in cholesterol, even when canned. Processed red meats like bacon and hot dogs are high in cholesterol.
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Saturated fat: Canned tuna made with oil has some saturated fat, but far less than fatty processed meats.
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Mercury: One of the only risks associated with tuna is mercury. No mercury is present in other processed meats.
So compared to bologna, salami, hot dogs, and bacon, canned tuna is a clear nutritional winner.
How Do Dietitians Classify Canned Tuna?
When making dietary recommendations, registered dietitians share the consensus that canned tuna is distinct from other processed meats:
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Dietitians group canned tuna with other seafood rather than with processed red meats.
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They recommend tuna as part of a high protein, anti-inflammatory diet but advise limiting true processed meats like bacon and hot dogs.
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Because the canning process is relatively simple, dietitians view canned tuna as only lightly processed compared with something like sausage.
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They may recommend rinsing canned tuna to reduce sodium intake. But overall, tuna remains recommended as an affordable, convenient protein source.
Canned Tuna in Food Guides and Dietary Guidelines
Major government and health organizations also endorse canned tuna as part of a nutritious diet:
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USDA’s MyPlate – Recommends 8-12 ounces of seafood, including canned tuna, weekly.
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American Heart Association – Encourages 2 servings of fatty fish like tuna to support heart health.
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American Cancer Society – Says tuna is a healthy protein choice and better alternative to processed deli meats.
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FDA & EPA – Advise limitations on tuna intake due to mercury risk, but do not group it with other processed meats.
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US Dietary Guidelines – Recommend seafood, including canned tuna, as protein alternatives to processed red and white meat.
The Verdict on Canned Tuna
Given its mild processing method and distinct nutritional profile, there is a strong case for categorizing canned tuna separately from more heavily processed red and white meats:
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With only salt, oil or water added, tuna undergoes less processing than hot dogs, sausage, bacon and deli meats.
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The core benefits of tuna like high-quality protein, omega-3s and vitamin D remain after gentle canning.
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Major health and dietary guidelines endorse canned tuna as part of a healthy diet, with mercury consumption as the main caution.
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From a sustainability perspective, tuna production has different impacts than meat and poultry farming.
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Allergies, intolerances and dietary restrictions around tuna differ from other processed meats.
While opinions vary on the degree to which canned tuna is processed, its health advantages and minimal preparation method set it apart from more aggressively processed meats. So armed with information on mercury risks, consumers can confidently enjoy canned tuna as part of a balanced approach.
Recommendations for Enjoying Canned Tuna
Here are some tips for selecting, preparing and eating canned tuna:
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Choose tuna packed in water when possible to reduce sodium intake. Flavor it yourself with healthy fats like avocado or olive oil.
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Opt for low-sodium versions or rinse tuna before use to further decrease sodium levels.
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Prioritize sustainably caught tuna like pole and line caught to support responsible fishing practices.
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Enjoy tuna in moderation, no more than 2-3 times per week according to mercury advisories.
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Try adding canned tuna to salads, sandwiches, pastas, rice bowls, and snacks for an easy protein boost.
At the end of the day, canned tuna is set apart from more highly processed meats like hot dogs and deli meat when it comes to both nutrition and processing methods. Keeping mercury guidance in mind, tuna canned in water can serve as an easy and healthful addition to your diet.
Is ultra-processed food harmful?
There are a number of health concerns related to ultra-processed food. Studies have shown that diets high in ultra-processed food tend to be linked with a higher risk of chronic disease (this is a recent review). And there has also been at least one large study that links excessive consumption of ultra-processed foods with increased cancer risk.
We don’t know for sure how ultra-processed food could affect health. They might not have as many healthy nutrients (like vitamins and minerals) as foods that have not been processed as much.
Some of the things that are added to food during processing are thought to cause cancer. For example, nitrites are often added to processed meats.
They also tend to have less fiber because the manufacturing process breaks down the structure of the original product. They also have more sugar and salt.
There is strong evidence that a “Western” diet, which includes eating a lot of ultra-processed food, makes people gain weight. We also know that overweight and obesity are a cause of at least 12 types of cancer.
But it’s the overall diet that is most important, rather than any one food, food group or nutrient. People are told to eat a healthy, well-balanced diet that includes lots of whole grains, vegetables, fruit, and beans and not too many “fast foods” or other processed foods that are high in fat, starches, and sugars, red and processed meat, and sugary drinks.
One way to get closer to eating the way we recommend for preventing cancer is to cut down on the amount of ultra-processed food you eat. Foods that are very processed seem to be a good indicator of how healthy a diet is; a diet that is low in these foods is usually healthier overall.
Processed culinary ingredients
These are ingredients that aren’t meant to be eaten by themselves but are often used with those in group 1. Examples include:
- oils
- fats such as butter
- vinegars
- sugars
- salt
This is when a group 2 product, like salt, sugar, fat, or vinegar, is added to one of those minimally processed foods.
This category includes:
- a lot of canned foods, like chickpeas, tomatoes, lentils, and beans
- food kept in brine, like olives
- salted nuts
- cheese
It also includes smoked and cured meats (that haven’t been made with reconstituted meat).
This includes foods that are usually made in a factory with tools and ingredients that separate the food and then put it back together again, often with artificial preservatives or other things that you wouldn’t find in a normal kitchen.
The list of foods that sit in this category is long and includes:
- pre-packaged meals (such as microwave dinners)
- industrialised bread
- breakfast cereals
- sweets, chocolate, biscuits and cakes
- sausages, chicken nuggets, veggie burgers
- soft drinks (eg cola, fruit drinks)
- crisps
- sweetened yoghurt
As was said in the introduction, this group accounts for 55.6 percent of the average British person’s calories. It is therefore clear that ultra-processed food has become the most popular type of food in the UK, at least.