What is a swai fish

Swai fish: should you eat or avoid it? (healthy or unhealthy?)

Swai fish is both affordable and pleasant to the taste. It is typically imported from Vietnam and has become widespread and popular in the United States over the past few decades.

However, many people who eat Swai are unaware that their production is problematic in overcrowded fish farms. This article will give you the facts about Swai fish and help you decide whether to eat or avoid them.

What is Swai and where does it come from?

Swai is a white-fleshed, moist fish with a firm texture and neutral taste. Hence, it easily takes on the taste of other ingredients. According to the US National Oceanic and Atmospheric Administration (NOAA), swai is the sixth most popular fish in the country. It comes from the Mekong River in Asia. However, swai that is available to consumers is most commonly produced in fish farms in Vietnam.

In fact, Swai production in Vietnam's Mekong Delta is one of the largest freshwater fish farming industries in the world. The Swai imported to the USA was previously called the Asian catfish. In 2003, the US Food and Drug Administration (FDA) passed a law that only fish from the Ictaluridae family, which includes the American catfish, but not Swai, can be labeled or advertised as catfish.

Swai comes from a separate but related family called Pangasiidae, and the scientific name for it is Pangasius hypophthalmus. Other names for Swai and similar species are panga, pangasius, sutchi, creme dory, striped catfish, Vietnamese catfish, tra, basa and - although it is not a shark - iridescent shark and Siamese shark.

Swai is a white-fleshed, tasteless fish that is typically imported from Vietnamese fish farms. Once referred to as the Asian catfish, U.S. law no longer allows the use of this name. American Catfish is from a different family than Swai, but they are related.

Nutritional value

The consumption of fish is generally encouraged as it provides lean protein and heart-healthy omega-3 fat. The protein content of Swai is average compared to other common fish, but offers very little omega-3 fat. A 4-ounce (113 gram) serving of uncooked swai contains:

  • Calories: 70
  • Protein: 15 grams
  • Fat: 1.5 grams
  • Omega-3 fat: 11 mg
  • Cholesterol: 45 grams
  • Carburetor: 0 grams
  • Sodium: 350 mg
  • Niacin: 14% of the reference daily dose (RDI)
  • Vitamin B12: 19% of the RDI
  • Selenium: 26% of the RDI

For comparison, the same serving of salmon has 24 grams of protein and 1,200-2,400 mg of omega-3 fat, while American Catfish has 15 grams of protein and 100-250 mg of omega-3 fat in 4 ounces (113 grams).

The sodium in Swai can be higher or lower than shown above depending on how much sodium tripolyphosphate, a moisturizing additive, is used during processing. Swai is an excellent source of selenium and a good source of niacin and vitamin B12. However, the amounts can vary depending on what the fish is being fed.

Swai don't have a particularly healthy diet. They are typically fed rice bran, soy, canola, and fish by-products. The soy and rapeseed products are often genetically modified, which is a controversial practice.

Swai is moderate in nutritional value and offers a decent amount of protein but very little omega-3 fat. Its main vitamins and minerals are selenium, niacin and vitamin B12. Using an additive to keep Swai moist increases its sodium content.

Concerns about Swai fish farming

The effect of Swai fish farms on the ecosystem is a major problem.

The Monterey Bay Aquarium’s Seafood Watch program lists Swai as a fish to be avoided because some Swai fish farms produce waste products that are illegally dumped into rivers.

Improper disposal of sewage is of particular concern as many chemical agents are used in Swai fish farms, including disinfectants, anti-parasitic agents and antibiotics. Another consideration is mercury contamination. Some studies have found acceptable levels of mercury in Swai from Vietnam and other southeast and southern areas of Asia.

However, other research has shown that the mercury content in Swai is above the limit recommended by the World Health Organization in 50% of the samples tested. These challenges suggest the need for better water quality in Swai fish farms and better quality control of the fish during the import process.

The Monterey Bay Aquarium’s Seafood Watch Program advises avoiding Swai as many chemicals are used on fish farms and can pollute nearby water. Some, but not all, analysis suggests that Swai could also be high in mercury.

Antibiotics are heavily used in production

When swai and other fish are raised in overcrowded fish farms, the risk of infectious diseases in the fish increases. In one study, 70-80% of Swai samples exported to Poland, Germany and Ukraine were contaminated with Vibrio bacteria, a microbe that is often implicated in food poisoning in shellfish.

To fight bacterial infections, Swai are often given antibiotics and other medications on a regular basis. However, there are downsides. Antibiotic residues can remain in the fish, and the drugs can end up in nearby bodies of water. In a study of imported seafood, Swai and other Asian seafood were the most likely to have exceeded drug residue limits. Vietnam had the highest number of drug residue violations among fish exporting countries.

In fact, 84,000 pounds of frozen Swai fish fillets imported from Vietnam and distributed in the US have been recalled for failing to meet US requirements to test the fish for drug residues and other contaminants. Even when fish are properly inspected and antibiotic and other drug residues are below legal limits, frequent use can increase bacterial resistance to the drugs. Some of the same antibiotics are used to treat human infections. When overused and the bacteria become resistant to them, it can leave people without effective treatments for certain diseases.

Antibiotics are widely used to fight infection in overcrowded Swai fish farms. Overuse of antibiotics increases the risk of bacterial resistance to them, which, in turn, could reduce the effectiveness of the medicine in humans.

You may be eating Swai fish unknowingly.

You could order Swai in restaurants without even knowing it.

In a study by Oceana, an international organization dedicated to protecting the seas, swai was one of the three species of fish that were most often replaced by more expensive fish. In fact, Swai was sold as 18 different species of fish - most commonly misnamed perch, grouper, or sole.

Such incorrect labeling can occur in restaurants, supermarkets and fish processing plants. Sometimes this mislabeling is a deliberate scam as Swai is inexpensive. Other times it's unintentional. Seafood often travels a long way from where it's caught to where it's bought, making it harder to trace its origin. For example, there is no easy way for restaurant owners to verify that a box of fish they bought is what it says it is.

Also, if a type of fish is not identified, such as when you order a fish sandwich at a restaurant where the type of fish is not specified, it could be Swai. In a study of seafood products served in 37 restaurants in the southeastern United States, about 67% of the items simply listed as "fish" on the menu were Swai.

Swai is sometimes intentionally or accidentally referred to as a different species of fish such as perch, grouper, or sole. Also, restaurants may not recognize the type of fish in some dishes, so there is a good chance you ate swai even if you didn't know.

A sensible approach to Swai and better alternatives

If you like Swai, buy eco-certified brands from an independent group like Aquaculture Stewardship Council. Such brands usually contain the certification body's logo on the packaging. The certification indicates efforts to reduce pollutants that can contribute to climate change and affect water quality.

Also, don't eat raw or undercooked swai. Cook fish to an internal temperature of 145 ℉ (62.8 ℃) to kill potentially harmful bacteria such as Vibrio. If you are passing Swai on, there are plenty of great alternatives. For white-fleshed fish, wild-caught US catfish, Pacific cod (from the USA and Canada), haddock, sole or flounder must be taken into account. For fish filled with omega-3 fatty acids, some of your best non-excess mercury-free options are wild salmon, sardines, herring, anchovies, Pacific oysters, and freshwater trout.

Finally, eat a variety of different types of fish instead of the same type all the time. This helps reduce the risk of overuse from potentially harmful pollutants in a species of fish.

When you eat Swai, choose a brand with an eco-certified seal, such as from the Aquaculture Stewardship Council, and cook it well to kill Vibrio and other harmful bacteria. Healthy alternatives to Swai include haddock, sole, salmon, and many others.


Swai fish have a mediocre nutritional profile and are best avoided. It is imported from densely packed fish farms where chemicals and antibiotics are used in excess, causing water pollution and health problems. It is sometimes mislabeled and sold as a higher quality fish. If you do eat it, choose a brand that has an organic certificate. In general, it is best to eat a variety of different types of fish. Healthy alternatives to Swai include haddock, sole, salmon, and many others.