Swai Fish: Should You Eat or Avoid It?

You may have tasted Swai fish. It is one of the most popular fishes in the US. Of course, it is not native to the United States, and it is imported mainly from Vietnam.

Swai is not only tasty, but also pretty affordable.

You may have acquired a taste for this very popular fish, but are you aware of the concerns that surround the production of Swai?

If you are not aware, this article is going to let you know everything you need to. So, buckle up and read on.

What is Swai?

Swai is a fish with white flesh. It has a firm texture, it is moist, and it offers a neutral flavor. Because of its neutral flavor, the fish is capable of taking on the flavor from all the ingredients you add to it while cooking. [1]

Did you know?

Swai is the 6th most popular fish in the United States. This data comes from NOAA (the US National Oceanic and Atmospheric Administration). [2]

Where does Swai come from?

Swai is not endemic to the United States. This fish is natively found in the Mekong River in Asia. However, growing consumerism has led to commercial production of Swai, and industrial farming of this fish has started worldwide.

Did you know?

Vietnam’s Mekong Delta has a Swai production industry, and it is one of the largest freshwater fish farming industries in the entire world.

The catfish controversy

Before 2003, Swai that was imported into the US were labeled as Asian catfish. In 2003, the US Food and Drug Administration stepped forward and passed a law which prohibited such naming. [3]

The law stated that only those fish that fall in the Ictaluridae family can be labeled as catfish. This means that the American catfish could be labeled as catfish, because it belonged to that family. Unfortunately, Swai doesn’t fall in the Ictaluridae family.

With the passage of the law, no one could label Swai as Asian catfish any longer.

Swai comes from the Pangasiidae family, and its scientific name is Pangasius hypophthalmus.

Swai is not the only name for this fish. It is popular by various other names including:

  • Basa
  • Tra
  • Vietnamese catfish
  • Striped catfish
  • Cream dory
  • Sutchi
  • Pangasius
  • Panga
  • Siamese shark
  • Iridescent shark

Though Swai is sometimes referred to as shark (see the two names at the last), it is not a shark.

Swai fish farming – things you should know

Mercury contamination

Swai fish farming impacts the ecosystem, and it has become a major concern. [4]

According to Monterey Bay Aquarium’s Seafood Watch, the farms involved in Swai fish farming generate a lot of waste products. These waste products are illegally dumped into rivers, and hence, the Seafood Watch program says that Swai should be avoided.

The waste product produced during Swai farming is a concern, because the farming process uses various anti-parasitic drugs, disinfectants, antibiotics, etc.

To top that, there is mercury contamination.

Several studies [5, 6, 7] have found that the mercury levels found in Swai coming from Vietnam and other southern and southeastern regions of Asia have acceptable mercury levels.

However, other research found high mercury levels (above WHO’s recommended level) in 50% of the Swai samples tested for mercury contamination. [8]

Mercury, beyond a certain limit, is harmful to the human body. Often, mercury-related health problems in humans are related to the food we consume.

Antibiotic usage

In crowded fish farms where Swai or just about any fish are grown, there is a significant increase in the risk of infectious diseases in fish.

This isn’t a hypothesis. It is a fact.

For instance, there was a study in which it was found that 70 to 80% of the Swai samples that Ukraine, Germany, and Poland imported had Vibrio bacteria contamination. This microbe is responsible for causing shellfish food poisoning in humans.

People involved in farming of Swai often resort to antibiotic usage to deal with viral infections. However, residues of antibiotics stay in the fish and often enter into the nearby waterways. [9]

Did you know?

Vietnam is a repeat violator in terms of drug residue in fish that it exports, and even worse, it tops the list of such violators. Many Asian countries that export seafood and Swai fall in that list, and they very often exceed the drug residue limits.

In 2017, 84,000 pounds of Swai fillet that were imported from Vietnam had to be recalled because of excess drug residues! [10]

Here is the problem – even if the exporters manage to stay within the allowed drug residue limits in the US, frequent use of such antibiotics tend to make the microbes resistant to those drugs.

The problem is that some of the antibiotics used for Swai are often used for treating humans. So, if the microbes become resistant, treatment becomes ineffective in humans. [11, 12]

You may have already eaten Swai!

You may think that you did not eat Swai, like, ever!

Are you sure about that? You may have unknowingly done so.

Did you ever hear the name of Oceana? It is an international organization that works towards and advocates for conserving our oceans.

Oceana conducted a study and found that Swai and two more fish are most commonly substituted for fish that are far more expensive.

In fact, Oceana found that Swai was replaced with 18 different types of fish including the famous sole, grouper, and perch.

Sometimes Swai is mislabelled by mistake. Other times, such mislabelling is intentional, because Swai is cheaper. In short, fraud is committed, and you can become a victim anywhere from restaurants to supermarkets. Such fraud can take place even in plants where seafood is processed.

So, when it is clear that fraud or accidental mislabelling happens, why can it be solved?

The reason is startlingly simple!

Seafood travels a very long distance, especially in case of imports. So, tracing its point of origin is nearly impossible. Do you really think that a restaurant will go out and investigate the origin point for a box of fish it buys?

One easy way to find out whether a restaurant is serving you fish or not is to see whether the menu specifically names the fish or not. If it only says something like ‘fish sandwich’ or simply lists the dishes as ‘fish,’ they are most likely serving you Swai.

If you like Swai, do this!

You may just love Swai. Many people do. But whatever you read above shouldn’t be a deterrent. If you absolutely want to eat Swai, make sure that you are going for brands that have earned eco-certification from some independent group.

An eco-certification ensures two things:

  • Proper initiative has been taken to reduce the pollutants contributing to climate change.
  • An eco-certification means that pollutants harming water quality have been reduced with a conscious effort.

What else can you do?

Make sure that you are properly cooking the Swai. Eating undercooked or even raw Swai puts you at risk. Make sure that you have a device to measure the internal temperature of the Swai fillet. The internal temperature should be at least 62.8 degrees Centigrade or 145 degrees Fahrenheit. At this temperature, potentially harmful microbes such as the Vibrio bacteria are killed.

If you are not a die-hard fan of Swai, it is better that you go for alternatives like wild-caught American catfish.

You can also settle for options like sole, haddock, Pacific cod (especially the ones caught in Canada, and the US), flounder, etc. All these fish have white flesh.

You can also settle for options like freshwater trout, Pacific oysters, anchovies, herring, sardines, and wild-caught salmons. These fish do not have excess mercury, and they are even high on Omega-3 fatty acids.

Swai nutrition content

Assuming that you want to eat Swai and that you have managed to get a good branded pack of fillet, here is the nutrition content of 113 grams or 4 ounces of raw Swai [13, 14, 15, 16]:

  • Protein: 15 grams.
  • Calories: 70.
  • Omega-3 fat: 11 milligrams.
  • Cholesterol: 45 grams.
  • Fat: 1.5 grams.
  • Sodium: 350 milligrams.
  • Carbohydrates: 0 grams.
  • Selenium: 26% of referenced daily intake (RDI).
  • Vitamin B12: 19% of RDI.
  • Niacin: 14% of RDI.

Take a close look at the values above. How much Omega-3 fat do you see? That’s a very insignificant amount.

If you replace Swai with the same quantity of American catfish or salmon, you will get 100-250 mg or 1,200-2,400 mg of Omega-3 fat respectively. [17, 18, 19]

One may argue that the selenium content is good is Swai, but that will definitely depend on what is fed to the fish during farming. The same argument holds for niacin, as well. [20, 21]

The problem with Swai farming is that the fish do not get a healthy diet. They are mostly fed fish byproducts, canola, soy, and rice bran. Of these, the canola and soy are mostly genetically modified, which is not a good practice. [22, 23]

Swai fun facts [24]

  • Swai has a shimmering skin that gives it the name iridescent shark.
  • Basa and Swai aren’t the same. The scientific name of Swai is Pangasius hypophthalmus. The scientific name of Basa is Pangasius bocourti.
  • Though Swai is endemic to Mekong and Chao Phraya, commercial breeders introduced it to large ponds and other rivers in Vietnam, Cambodia, Laos, and Thailand.
  • Swai is omnivorous.
  • Swai have increased amounts of red blood cells in their blood, allowing them to warm waters that have low oxygen levels.
  • Swai is capable of breathing directly from the air.
  • In natural habitat, Swai can grow up to 4 feet, and weigh as much as 97 pounds.
  • Swai meat has less nutritional value than Basa. Basa meat has a superior taste.
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