Fish is a nutrient-packed food recommended as part of a balanced diet. However, some options may be healthier than others regarding eating fish.
The healthiest fish to eat are low in contaminants and rich in nutrients like omega-3 fatty acids, iodine, selenium, vitamin D, and amino acids. Many types of fish are also low in calories and high in protein. Regular fish consumption may benefit heart health, metabolic health, and hormonal balance. Fish may also help older adults maintain muscle mass.
Top 5 Healthiest Fish to Eat
The healthiest fish are rich in nutrients like omega-3 fatty acids and low in contaminants like mercury. Although sustainably farmed or caught fish are viable options, there are important considerations to keep in mind.
Contaminants like mercury can harm brain development. Choosing fish low in mercury is essential, especially during pregnancy, lactation, and in children. Low-mercury fish include anchovies, Atlantic mackerel, catfish, crawfish, flounder, haddock, mullet, plaice, pollock, salmon, sardines, shad, sole, tilapia, trout, and whiting.
Whether wild-caught or farm-raised, sustainably sourced fish may benefit the environment and long-term health. However, sustainable fish don't always offer more nutrition or benefits and can also be expensive and hard to find, making them a potentially unrealistic option.
The following highlights the top five healthiest fish to eat.
1. Salmon
Renowned for its delicate flavor and rich nutritional profile, salmon is a versatile fatty fish with many health benefits.
Benefits: Salmon is high in omega-3 fatty acids and low in mercury, making it a healthy, low-contaminant choice. Salmon contains additional nutrients that support your overall health, including protein, amino acids, and various vitamins and minerals, like vitamin D, iron, calcium, and potassium. Salmon also contains antioxidants such as vitamin E, vitamin C, and selenium.
Best Sources Salmon found in grocery stores may come from rivers, oceans, or fish farms. According to one study, farm-raised and wild-caught salmon have statistically similar nutrition profiles, meaning one isn't necessarily healthier. Farm-raised salmon may contain antibiotics and other components not found in wild-caught salmon. While some countries regulate the amount of antibiotics a fish farm can use, others do not.
2. Mackerel
"Mackerel" is the name given to various fish of the Scombridae family that live in oceans around the world. The following includes its nutritional benefits and more.
Benefits: Mackerel are high in omega-3 fatty acids and other healthy fats. Atlantic mackerel is a sustainable and healthy choice, containing lean protein, calcium, magnesium, potassium, selenium, and B vitamins. It is also an excellent source of vitamin D. A 3-ounce serving provides over 500 international units (IU), nearly 100% of the recommended daily intake (RDI).
Best Sources: When choosing mackerel, you may want to consider factors like contamination and taste. Atlantic mercury is a low-mercury fish. However, king mackerel is high in mercury. Pregnant people should limit their intake of high-mercury fish like king mackerel to avoid potential harm to fetal brain development.
3. Sardines
Sardines are small, inexpensive, nutritious fish with several potential health benefits, such as the following.
Benefits: As an oily fish, sardines are a good source of omega-3 fatty acids. They are also high in calcium, with 100 grams (g) meeting almost 40% of the RDI for most adults. In addition to omega-3s and calcium, sardines contain other heart-healthy nutrients, like potassium, magnesium, zinc, and niacin. Sardines are also higher in iron than many other types of fish. Eating them may help you meet your iron needs.
Best Sources: Since they tend to live near coastlines, some types of wild sardines may contain mercury and other contaminants. However, sardines are still considered a low-contaminant fish. Canned sardines are a popular option, but they are also available fresh. All types of sardines are thought to provide various health and nutritional benefits. However, canned sardines may be higher in sodium than fresh sardines.
4. Rainbow Trout
Known for its low contaminant levels and high nutritional value, rainbow trout is a heart-healthy fish packed with essential nutrients.
Benefits: Like other types of oily fish, rainbow trout are a good source of heart-healthy omega-3 fatty acids. A 3-ounce serving of rainbow trout also contains protein, calcium, magnesium, phosphorus, potassium, zinc, selenium, niacin, vitamin D, and other vitamins and minerals. Rainbow trout is a heart-healthy, lean fish due to its high protein and low saturated fat content.
Best Sources: Rainbow trout may be farmed or wild and is considered safe to eat. In terms of nutritional value, wild rainbow trout tend to be slightly higher in certain nutrients, like protein, calcium, iron, magnesium, and B vitamins. Due to their diets, wild rainbow trout typically have lower mercury levels than some other types of fish. In the United States, rainbow trout farming is considered a sustainable, environmentally friendly option.
5. Anchovies
Anchovies are small, nutrient-dense fish with a salty flavor, which some consider an acquired taste. They tend to be safely fished and may be considered a sustainable choice.
Benefits: Despite their small size, the nutritional benefits of anchovies rival much larger fish. A serving of anchovies provides 17 g of protein and plenty of omega-3 fatty acids. You'll also find calcium, iron, magnesium, potassium, B vitamins, and plenty of other vitamins and minerals in anchovies. Some types of anchovies may be higher in sodium, so some people with certain health conditions may need to limit their intake.
Best Sources: The FDA recommends anchovies as a low-mercury fish. Anchovies are typically caught in the wild and processed before they reach the grocery store aisles. During processing, anchovies are salted and cured. However, you can also purchase fresh anchovies.
Fish to Limit or Avoid
Some fish can contain heavy metals like mercury and other contaminants, which may pose health risks, particularly for vulnerable populations. Fish to limit or avoid include the following.
1. High-Mercury Fish
Mercury can harm brain development, particularly in children. The Food and Drug Administration (FDA) and the Environmental Protection Agency (EPA) determined the best fish for eating three servings per week contains less than or equal to 0.15 micrograms per gram (mcg/g) of mercury.
The FDA also suggests people avoid fish with mercury levels over 0.46 mcg/g, especially in sensitive populations like children, during pregnancy, or breastfeeding.
If you do not fit into these populations, consuming high-mercury fish on a limited basis may be OK. However, check with a healthcare provider if you have concerns.
According to the FDA, king mackerel, marlin, orange roughy, shark, swordfish, tilefish from the Gulf of Mexico, and bigeye tuna contain the highest mercury levels and should be limited or avoided.
2. Fish High in Other Contaminants
Research shows that fish and other animal products are common sources of persistent organic pollutants (POPs). These include polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), dioxins, and chlorinated pesticides, which tend to end up in bodies of water where fish live.
POP levels in fish tend to vary by their size, fat content, location in the food chain (and therefore what they eat), and where they are fished. POPs may be carcinogenic (cancer-causing), but more research is needed.
The European Food Safety Authority (EFSA) suggested a limit of 2 picograms per kilogram of body weight (pg WHO TEQ-05/kg bw) for dioxin-like contaminants.
3. Overfished Species
Overfishing, or the fishing of too many fish, is a potential environmental problem. It puts fish species at risk for depletion and highlights the potential for more sustainable fishing practices.
Fish at risk for overfishing include Atlantic cod and some types of tuna, including albacore.
Is Tuna Good for You?
Specific types of tuna have higher mercury levels, while others are low in mercury.
Canned light tuna (typically skipjack tuna), albacore, and yellowfin tuna tend to contain lower mercury levels compared to other types of tuna.
The FDA recommends no more than two or three 4-ounce servings of canned light tuna per week or one serving of albacore or yellowfin tuna per week.
Bigeye tuna is high in mercury and should be avoided during pregnancy, while breastfeeding, and in children.
Health Benefits
Research shows that regularly eating fish may have health benefits, including improved heart health and cognitive function. These benefits stem from fish's nutrient-rich profile, which includes vital nutrients such as protein and key amino acids.
Nutrition: Fish tend to contain high-quality protein. However, they're unique as many are also a good source of omega-3 fatty acids and other healthy fats. Omega-3s benefit cell membranes in the brain and more, provide energy, and support heart and eye health.
Fatty or oily fish tend to contain the highest levels of omega-3s. Fish contain varying levels of vitamins and minerals, including vitamins A and D, B vitamins, calcium, iron, and zinc. It also has iodine and selenium for thyroid health and vitamin D for bone health, calcium absorption, and inflammation control. Taurine, an amino acid, is also present in fish and supports blood lipids and heart health.
Studied Benefits: It's well known that eating fish benefits your health. Several studies have associated fish consumption with heart health benefits, likely due to its high omega-3 fatty acid content. Omega-3 fatty acids from fish have reduced brain inflammation, improved mental performance, and potentially improved blood flow to the brain. Regular consumption of fish and other nutrient-dense foods may promote bone health, decrease the risk of certain cancers, and help maintain weight.
Incorporating fish into your diet has the potential to improve your overall health and well-being.
How Much Fish Should I Eat?
Avoid fish if you are allergic. Otherwise, the Dietary Guidelines for Americans and the FDA recommend the following amounts of fish per week:
Adults: At least 8 ounces
Pregnant or breastfeeding people: 8 to 12 ounces of low-mercury fish
Children: 8 ounces or less of low-mercury fish
How much fish you eat is a personal choice, guided by considerations like your dietary preferences and goals.
Summary
Fish are generally recommended as part of a well-balanced diet. However, some fish may be healthier than others. Salmon, mackerel, sardines, rainbow trout, and anchovies are five of the healthiest fish to eat. The healthiest fish are rich in nutrients, like omega-3 fatty acids, and low in contaminants, like mercury. Sustainably sourced fish may be a consideration.
Fish like king mackerel, marlin, orange roughy, shark, swordfish, tilefish from the Gulf of Mexico, and bigeye tuna, which contain the highest mercury levels, should be limited or avoided.