Is canned fish healthy? The No. 1 pick to start eating right away, according to dietitians

Canned fish seems more popular than ever. Whether it’s the rising prices of groceries or TikTok’s #tinnedfish obsession, this shelf-stable, lean protein source is having a moment.

Despite the recent traction, canned seafood or “conservas” have been around for over a century. It’s commonly eaten in many parts of Europe and Asia, and a menu specialty in Portugal and Spain.

But is canned fish actually good for you? Which types are the healthiest? Here’s what dietitians think.

Is canned fish healthy?

Fish is rich in many key nutrients, including protein, omega-3 fatty acids, essential vitamins and minerals. That’s why U.S. Dietary Guidelines and the American Heart Association recommend fish as part of a healthy eating pattern.

“We’re supposed to be eating two or more servings of fish each week,” Frances Largeman-Roth, registered dietitian nutritionist, tells TODAY.com.

Tinned fish provides the same nutrients and benefits but in a pre-cooked, shelf-stable, convenient package.

“Due to lack of cooking skills when it comes to seafood, combined with high prices of the fresh stuff, many of us are not eating enough fish,” says Largeman-Roth. Research suggests that about 90% of Americans don’t eat the recommended amount of fish.

“Canned fish is a great way to meet the recommendation and get the nutrients you need in an affordable way,” says Largeman-Roth.

Depending on where you live and grocery shop, fresh or even frozen fish may not be readily available, Julia Zumpano, a registered dietitian with Cleveland Clinic’s Center for Human Nutrition, tells TODAY.com. “Canned fish can allow for more frequent intake of fish at a lower cost and in areas where fish is less accessible.”

Canned fish is fully cooked or smoked before it is sealed in an air-tight can, Largeman-Roth notes, which makes it safe to eat as is. “You can keep canned fish in your pantry for two to five years, depending on how it was packaged and processed,” Largeman-Roth adds.

Is canned fish high in mercury?

Nearly all fish contains trace amounts of mercury from the water, which gets absorbed by fish when they feed, per the U.S. Food and Drug Administration. For most people, the risk of mercury exposure through eating fish is not a health concern, the FDA says.

However, at higher levels, mercury can be toxic to adults or harmful to pregnant women and young children. The degree of mercury exposure depends on the amount and type of fish eaten, per the Environmental Protection Agency.

Certain canned fish are lower in mercury and safe to eat more often than others.

How to choose a healthy canned fish

Most tinned fish can be healthy, the experts note, but some are more nutritious and contain fewer added ingredients and contaminants. Overall, when choosing between canned varieties of the same fish, Zumpano recommends opting for the following:

• Packed in water or extra virgin olive oil
• Lower in sodium
• Lower in mercury
• Wild or safe-caught
• Packed in a BPA-free can

When it comes to fish packed in water or oil, the experts say both can be healthy. “Water is better than oil unless it is in extra virgin olive oil,” says Zumpano.

Although fish packed in olive oil contains more calories, it also has more healthy fats and nutrients from the oil, as well as a richer flavor, the experts note.

As with any food, moderation is key. One serving of canned fish is about 3 to 4 ounces, or the size of an adult’s palm. The experts also recommend varying your seafood sources each week.

What are the healthiest canned fish?

Sardines

Sardines are a favorite among dietitians for many reasons: They are high in protein, nutrient-dense and low in mercury. In fact, sardines came in as the healthiest fish, according to registered dietitian and TODAY.com contributor Samantha Cassetty.

According to the U.S. Department of Agriculture, one serving or can of the average store-bought sardines packed in oil provides about:

• 200 calories
• 22 grams of protein
• 12 grams of fat
• 200-300 milligrams of sodium

“Sardines are an excellent source of protein,” says Largeman-Roth. The small, nutrient-dense fish are also packed with omega-3 fatty acids, a type of polyunsaturated fat that can help support heart, brain, skin and immune health.

Foods high in omega-3s can help increase good (HDL) cholesterol and can lower bad (LDL) cholesterol.

Sardines are also packed with vitamin D, vitamin B12, calcium, phosphorus and selenium, Zumpano notes. They are also a good source of potassium, iron, zinc and choline.

Sardines are one of the lowest-mercury fish you can buy. They’re considered a “best choice” fish by the FDA, and are safe to eat in moderation for pregnant women and children.

Sardines can be enjoyed straight from the can with crackers, on top of a bed of salad or rice, or in pasta sauces.

Wild salmon

Salmon is another front-runner that packs in protein, healthy fats, and other nutrients the body needs.

According to the USDA, 3 ounces of canned sockeye salmon, without skin and bones, drained, provides about:

• 167 calories
• 23 grams of protein
• 7 grams of fat
• 300 milligrams of sodium

Just like fresh salmon, canned salmon is an excellent source of protein and omega-3 fatty acids — and very affordable at about $6.50 a can, says Largeman-Roth.

Omega 3 fatty acids have been proven to decrease triglycerides (a type of fat found in the blood), blood pressure, risk of death and blood clots, Zumpano notes. “Salmon is also low in mercury (and) a good source of vitamin B12 and vitamin D,” Zumpano adds.

Just one 3-ounce serving of canned salmon provides 25% of the daily vitamin D requirement, plus calcium, iron and potassium, Largeman-Roth adds.

The experts recommend wild-caught sockeye or pink salmon, which is more sustainable and lower in contaminants.

Canned salmon can be used to make salmon burgers, added into sushi rolls or onigiri (rice balls), or used in place of tuna in a salad.

Light tuna

Tuna is one of the most popular canned fish around. It’s a convenient source of lean protein, versatile and cheap.

According to the USDA, one can of the average light tuna packed in water, drained, provides about:

• 142 calories
• 33 grams of protein
• 1.5 grams of fat
• 200-300 milligrams of sodium

Canned tuna provides an impressive amount of protein — over 30 grams per can — and packs in other valuable nutrients, including selenium, iron and vitamin B12, experts note.

Tuna is lower in fat than other popular canned fish varieties like sardines, but also comparatively lower in heart-healthy omega-3 fatty acids, says Zumpano.

There’s one big catch: Not all canned tuna is the same.

“Tuna can be high in mercury, so choose canned varieties that are tested for mercury and are lower than average canned tuna,” says Zumpano. These include smaller tuna species, such as skipjack, which may be sold as “light” or “chunk light,” says Largeman-Roth.

Canned albacore (white) tuna and yellowfin tuna are higher in mercury and should be eaten less, TODAY.com previously reported.

Tuna is versatile and delicious. “Simply add any ingredients you like, from mayo and olive oil to lemon juice and fresh herbs, and you can have a meal in minutes,” says Largeman-Roth.

Mackerel

Mackerel is a tasty and nutritious alternative to canned sardines, salmon and tuna.

According to the USDA, one serving (a standard can or 75 grams) of canned mackerel provides about:

• 117 calories
• 17 grams of protein
• 4 grams of fat
• 200-300 milligrams of sodium

Mackerel is also rich in protein and heart-healthy omega-3 fatty acids, per the Cleveland Clinic. These nutritious fish are also packed with B and D vitamins.

As with tuna, not all mackerel is the same. It’s important to choose Atlantic or Pacific chub mackerel, which are lower in mercury. Avoid king mackerel, which is high in mercury, per the FDA.

Anchovies

Anchovies are small but mighty when it comes to nutrients. Although they often get a bad rap, canned anchovies have a number of benefits.

According to the USDA, one serving (about five flat filets or 20 grams) of anchovies, packed in oil, drained, provides:

• 42 calories
• 5 grams of protein
• 2 grams of fat
• 735 milligrams of sodium

These small, oily fish are loaded with nutrients, including protein, omega-3s, calcium and selenium, an antioxidant that protects cells from damage that can lead to heart disease, cancer and other health issues.

Anchovies are typically salt-cured and packed in oil. They can add a salty, umami flavor to dressings, pasta sauces and pizzas. However, they are much higher in sodium compared to other tinned fish varieties, which is why the serving size is much smaller.

If you are on a sodium-restricted diet, consider limiting or avoiding anchovies, says Zumpano, but always talk to your doctor first.

Which canned fish is unhealthy?

The FDA recommends avoiding king mackerel, bigeye tuna, marlin, shark, swordfish, tilefish and other fish with higher mercury levels. Fortunately, these bigger fish aren’t commonly sold in cans, so they are relatively easy to avoid in the canned seafood aisle.

“There really isn’t an unhealthy canned fish,” says Largeman-Roth. However, some types of canned fish are less healthy due to the added ingredients or processing, Zumpano notes. These include canned fish that are:

• Packed in processed oils
• High in sodium
• In BPA cans

When possible, try to opt for wild or sustainably-caught fish over farm-raised or imitation varieties, Zumpano notes.

Is it safe to eat canned fish every day?

Canned fish is recommended as part of a healthy diet, but in moderation. It may be safe for some people to eat low-mercury canned fish daily, the experts note. “It depends on what you’re eating and who you are,” says Largeman-Roth.

Canned fish that are higher in mercury should not be eaten daily, the experts note. These include albacore or white tuna, yellowfin tuna, and Spanish mackerel, per the FDA. The recommendation for higher mercury fish is to eat it no more than once a week.

Recommended seafood intake is at most 12 ounces per week, Zumpano adds. If you are consuming a few ounces of canned fish each day while staying within the weekly limit, it should not be a concern, she adds.

“The FDA recommends that women who are pregnant or planning to become pregnant eat two to three servings of low mercury fish each week,” says Largeman-Roth.

The best bet is to vary the type of seafood you eat to avoid potential mercury exposure and environmental contaminants, Largeman-Roth adds.

Risks of canned fish

Canned fish is generally safe if you consume the recommended amount. “Avoid canned fish if you have an allergy (or sensitivity) to fish,” says Zumpano.

People on a sodium-restricted diet should limit their intake of tinned fish and opt for varieties that are lower-sodium or have no salt added, the experts note. “(Higher sodium) varieties can cause elevated blood pressure if total sodium intake is not being monitored,” Zumpano adds.

“Make sure to avoid buying cans that are dented or bulging or leaking, as the product inside may be contaminated,” says Largeman-Roth. Any unfinished canned fish should be placed in an airtight container and enjoyed within a few days.

This article was originally published on TODAY.com