Canned fish is a shelf-stable food that is convenient, budget-friendly, and nutritious. However, some people question whether canned fish is as healthy as fresh fish. There are concerns about the canning process, sodium content, and contamination with toxins like mercury. This article reviews the evidence on the nutrition, safety, and health effects of canned fish to help you decide if it should be part of a healthy diet.
Common types of canned fish
Some of the most popular types of canned fish include:
- Tuna
- Salmon
- Sardines
- Anchovies
- Mackerel
These fish are canned in water, oil, or sauces. Canned tuna is one of the most widely consumed, while sardines and salmon are also common choices.
Nutrition in canned fish
Canned fish is highly nutritious, providing protein, healthy fats, vitamins, minerals, and antioxidants. A 3-ounce (85 gram) serving contains:
- 116–189 calories
- 22–25 grams protein
- 2–15 grams fat
- Calcium: 4–43% of the Reference Daily Intake (RDI)
- Iron: 8–20% of the RDI
- Potassium: 5–28% of the RDI
- Vitamin D: 39–154% of the RDI
- Selenium: 47–163% of the RDI
The exact nutrition varies by fish type and canning method. Key nutrients in canned fish include:
Protein
Canned fish provides high-quality protein with all essential amino acids required for building muscle, bone, enzymes, hormones, and antibodies. The protein content ranges from 22–25 grams per 3-ounce serving.
Omega-3 fats
Fish are rich in the omega-3 fats EPA and DHA, which provide anti-inflammatory effects. Canned salmon, sardines, and trout are among the best sources.
Vitamin D
Fatty fish naturally contain vitamin D, a fat-soluble vitamin lacking in many people’s diets. Just 3 ounces (85 grams) of canned salmon provides over 100% of the recommended intake of vitamin D.
Calcium
Bones of canned sardines, salmon, and other fish are soft, edible, and rich in calcium. Per serving, you can get 4–43% of the recommended calcium intake from canned fish.
Selenium
A trace mineral important for thyroid and immune function, selenium is abundant in seafood. Canned tuna, sardines, anchovies, and mackerel are excellent sources.
Does canning affect the nutritional content?
Canning does result in some loss of heat-sensitive nutrients like vitamin C and B vitamins. However, levels of protein, healthy fats, minerals like calcium and potassium, and fat-soluble vitamins A, D, E, and K remain stable.
Canning also makes fish bones soft and edible, providing additional nutrition like calcium, phosphorus, and iron. Overall, canned fish has impressive nutrition and is comparable to fresh fish.
Is canned fish safe to eat?
There are some concerns related to toxins, contaminants, and food safety with canned fish. However, fish processors follow strict regulations to ensure canned products are safe.
Mercury and other contaminants
Large, predatory fish accumulate high levels of mercury and other pollutants. However, the FDA monitors contaminants and enforces cut-off limits for concentrations in seafood.
Brands test canned fish from each catch for contaminants and toxins. Fish like light tuna, salmon, anchovies, and herring have very low mercury levels and are safe when consumed in recommended amounts.
Bisphenol A (BPA)
BPA is an industrial chemical used in plastic manufacturing. Some early studies linked BPA from can linings with health risks. However, today, manufacturers use BPA-free cans or linings made with alternate materials.
Sodium content
While fresh fish is naturally low in sodium, salt is added to canned fish for flavor and preservation. The sodium content per 3-ounce serving ranges from:
- 150–350 mg in tuna canned in water
- 200–500 mg in tuna canned in oil
- 350–800 mg in salmon
- 500–1,100 mg in sardines
To limit sodium intake, choose low-sodium or no-salt-added versions when available. Be sure to drain and rinse the fish before use to remove up to 40% of the sodium.
Presence of histamine
Histamines can accumulate in spoiled fish. Good manufacturing processes help control histamine production in canned products. Regulations require testing canned fish for histamines to ensure low levels.
While allergies vary, most people tolerate the low histamine levels in commercially canned fish. However, those with histamine intolerance may need to avoid it.
Botulism risk
Botulism is a severe form of food poisoning caused by the toxins from Clostridium botulinum bacteria. To prevent botulism, canned goods are heated to 250°F (121°C) to kill bacteria and spores before canning.
Properly processed canned fish does not contain botulinum toxins. Cases of botulism from fish are extremely rare and linked to home canning errors.
Shelf life
Commercially canned fish has a shelf life of at least 2–5 years. The can protects against recontamination while the high heat processing destroys bacteria that could make you sick.
For optimal quality, it’s best to use canned fish within 2 years. Older cans that are heavily dented, leaking, rusted, or bulging should not be consumed.
Health benefits of canned fish
Despite the high sodium content, studies consistently link canned fish intake to improved cardiovascular health and other benefits:
Heart health
Eating 1–2 servings of fatty fish per week reduces heart disease risk by 36%, according to a study in over 600,000 people. The anti-inflammatory omega-3s EPA and DHA play a major role.
Other studies show canned fish or tuna 1–3 times per week lowers triglycerides and blood pressure while raising HDL (good) cholesterol. The benefits appear similar for canned versus fresh fish.
Reduced risk of stroke
A study in over 80,000 women found those who ate 2–4 servings of canned tuna or other broiled or baked fish per week had a 27% lower risk of stroke compared to those who ate it once monthly.
Less cancer risk
Research links higher intakes of omega-3 rich fatty fish to lower risks of prostate, breast, and colon cancers. In one study, just one serving of canned tuna or other fish per week cut prostate cancer risk by 25%.
Better brain health
The omega-3s in fish also benefit the brain and nervous system. Eating fish weekly appears to lower dementia risk by 13–15% and reduce age-related mental decline.
Healthy aging
A study in Chinese adults 65 or older found those who consumed canned fish 3-4 times a week showed better cognition and fewer symptoms of depression versus non-consumers.
Good for moms and babies
During pregnancy and lactation, omega-3s support fetal brain development while choline benefits attention and memory. Canned fish provides these and other nutrients to support healthy growth.
Potential concerns
Despite the benefits, there are some potential downsides to canned fish:
High sodium
To limit the adverse effects of sodium on blood pressure and stroke risk, the AHA recommends no more than 2,300 mg per day. One serving of canned fish can provide up to 40% of this amount.
Those with hypertension or at high risk should limit sodium intake to 1,500 mg per day. High intakes from canned fish could contribute to issues.
Not ideal for mercury
Mercury builds up in larger, long-lived fish like tuna, swordfish, shark, tilefish, and king mackerel. Young children and pregnant women are advised to limit intake of these fish.
Canned light tuna is lower in mercury but should still be eaten in moderation. Albacore or white tuna has 3 times the mercury of canned light tuna.
High histamine for some
Most people can tolerate the low histamine levels in canned fish. However, those with sensitivities may experience headaches, flushing, sweating, and heart palpitations after eating canned products.
Allergies
Fish is one of the most common food allergens, especially among children. An allergy to one type of fish often means needing to avoid all fish. Speak to your doctor about diagnosis and management of fish allergies.
Acrylamide formation
Frying or roasting fish at high temperatures may produce acrylamide, a potentially carcinogenic compound. However, acrylamide is not a concern with lower temperature commercial canning methods.
Canned fish for different diets
Here’s how canned fish may fit into different dietary patterns:
Keto and low carb diets
Canned fish is a zero carb food rich in protein and heart-healthy fats that supports ketosis. Try salmon, sardines, or mackerel. Limit brined fish packed in sugary sauces.
Vegetarian and vegan
Most canned fish is off limits for vegetarians and vegans. The exception is vegetarian omega-3 long chain fatty acids from microalgae, which are added to some canned tuna.
Paleo diet
Canned fish fits well in the Paleo diet as it involves minimally processed, wild-caught seafood. Salmon, sardines, mackerel, and anchovies are good choices.
Gluten-free diet
Plain canned fish contains no gluten. However, some canned tuna, salmon, and sardines are packed in sauces that may contain gluten from wheat, barley, rye, or oats. Check labels carefully.
DASH diet
The DASH diet for blood pressure control limits processed foods and sodium, so plain canned fish in water is the best option. Keep intake moderate to avoid excess sodium.
Mediterranean diet
Canned fish like salmon, sardines, mackerel, and anchovies fit well in the Mediterranean diet given their high omega-3 content. Choose versions canned in olive oil when possible.
How to add more canned fish to your diet
Here are simple ways to eat more canned fish for better health:
- Make tuna, salmon, or sardine salad sandwiches or wraps using low carb or whole grain bread.
- Add canned salmon, tuna, or anchovies to leafy green salads, grain bowls, pasta dishes, and pizza.
- Make salmon patties or crab cakes using canned fish.
- Try fish tacos with canned tuna, salmon, or anchovies.
- Add canned sardines, anchovies, herring, or mackerel to toast, crackers, and antipasto platters.
- Make canned tuna and cracker snacks or tuna melts.
- Add canned salmon to egg dishes like omelets and frittatas.
- Include canned fish in pasta sauces, casseroles, soups, and stews.
- Use canned salmon or tuna in place of raw fish in sushi rolls, poke bowls, and ceviche.
Aim for 1–2 servings (3–6 ounces) of canned fish per week as recommended for optimal health. Try different types to take advantage of their unique nutritional benefits.
The bottom line
Canned fish like tuna, salmon, sardines, and mackerel is nutritious, affordable, and shelf-stable. It provides high-quality protein, healthy omega-3 fats, minerals, and various vitamins.
Research consistently links canned fish intake to better heart health, reduced risk of chronic disease, and lower mortality. However, those with hypertension, elevated mercury levels, or allergies may need to limit intake.
When shopping, opt for low sodium versions canned in water. Rinsing before use reduces sodium further. Stick to smaller fish lower in mercury like light tuna, salmon, sardines, or herring when possible.
Overall, canned fish is a convenient way to get needed nutrients into your diet and supply the health benefits of fish. Buying sustainable options helps support the health of our oceans too.
Frequently asked questions
Is canned fish healthier than fresh fish?
Canned fish is very healthy and comparable to fresh fish. Canning makes fish more affordable, convenient, and shelf-stable but does result in some losses of vitamins. However, protein, healthy fats, minerals, and fat-soluble vitamins are preserved.
Is canned tuna good for you?
Yes, canned tuna is nutritious. It provides high-quality protein, omega-3s, vitamins, and minerals. Studies link canned tuna intake 1–3 times per week with lower heart disease risk factors. However, limit white or albacore tuna which is higher in mercury.
Is canned salmon healthy?
Absolutely. Canned salmon is an excellent source of protein plus anti-inflammatory omega-3s, vitamin D, calcium, iron, and other nutrients. The bones in canned salmon are soft and edible, providing extra nutrition like calcium and phosphorus.
Are canned sardines good for you?
Yes, canned sardines and other small fish like herring, anchovies, and mackerel are very healthy. They provide omega-3 fats, high quality protein, calcium, selenium, and various vitamins and minerals.
Is it okay to eat canned fish daily?
Eating canned fish daily should be fine for most healthy people. Getting 3-6 ounces every day can help you meet recommendations for healthy omega-3 intake. However, limit tuna to a couple times a week to minimize mercury exposure.
Conclusion
Canned fish offers an affordable, shelf-stable way to get the health benefits of seafood. While fresh fish is great, canned varieties like tuna, salmon, sardines, herring, and mackerel provide similar nutrition in a convenient package.
Studies show those who eat canned fish 1-3 times weekly have better heart health, reduced inflammation, and lower risks of chronic disease. However, it’s wise to choose low sodium options and limit tuna and other fish higher in mercury.
Aim to include a serving or two of canned fish per week as recommended. Rinse before use to remove excess sodium. The right amount can supply key nutrients without the risks. For an optimal diet, enjoy canned fish along with plenty of fruits, vegetables, whole grains, plant proteins, low fat dairy, and healthy oils.