Health Benefits of Swai (Pangasius, Basa, or Tra)

Swai (Pangasianodon hypophthalmus) is a farmed freshwater catfish from the Mekong River in Vietnam. You may also see swai referred to as pangasius, basa, or tra. It has grown in popularity in the United States for its low cost, mild flavor, and health benefits. Swai is a good source of protein, micronutrients, and vitamins.

Researchers have several ethical and environmental concerns about how swai is produced. Swai has more sodium and a higher risk of contamination than other locally grown catfish. The U.S. Food and Drug Administration (FDA) labels swai as one of the most commonly mislabeled types of fish.

Provides Lean Protein

Swai is a good source of protein without high amounts of saturated fat. However, this also means swai is low in omega-3 fatty acids.

Lean protein like swai reduces the risk of high cholesterol commonly associated with chicken and red meat. Eating excess saturated fat can increase your risk of developing heart disease by contributing to a build-up of low-density lipoprotein (LDL) cholesterol on your artery walls.

Each swai fillet contains up to 19 grams (g) of protein. Eating an adequate amount of protein helps to keep your bones and muscles strong. 

Good Source of Micronutrients

Swai is a good source of many essential micronutrients, including selenium, phosphorus, zinc, and certain B vitamins. Selenium is important for thyroid health, infection prevention, and DNA synthesis. Micronutrients in swai can also improve reproductive health and protect against oxidative stress, which can lead to illness and infection.

The B vitamins in swai include niacin, thiamin, vitamin B12, pantothenic acid, and biotin. B vitamins in swai can help keep your body energized by assisting with the production of ATP (adenosine triphosphate)—a molecule that stores energy in your cells.

Other nutrients like zinc support immune health, wound healing, and protein synthesis.

Nutrition

Swai is a lean protein with less saturated fat than other types of fish. Although consuming less saturated fat is good for your health, swai is also higher in sodium than many other types of fish. Fatty fish like salmon and haddock have more nutrients than swai.

A 4-ounce (112-gram) swai fillet has the following nutrition profile:

• Calories: 80 cal
• Fat: 0.5 grams (g)
• Sodium: 30 milligrams (mg)
• Carbohydrates: 0 g
• Fiber: 0 g
• Added sugars: 0 g
• Protein: 19 g
• Cholesterol: 50 mg

Fatty fish like salmon or sea bass are better sources of omega-3 fatty acids than swai. Omega-3 fatty acids help reduce inflammation in your body. They also benefit your heart, immune, and respiratory health.

High amounts of sodium in swai may be especially harmful for people with high blood pressure. Excess sodium can raise blood pressure. Fish like salmon and mackerel may be a better protein option for managing your blood pressure.

Risks

Swai are typically grown in rivers with an increased risk of contamination. This makes swai prone to unsafe levels of mercury and other chemicals. One study found a range of mercury concentrations in different frozen swai fillets. In another study, 50% of the swai tested had mercury levels beyond the recommended limit.

Furthermore, one study evaluating swai fish exported to countries like Ukraine and Poland found that 70%–80% of swai used tested positive for vibrio—a bacteria that can cause food poisoning.

Many fish farmers in Vietnam rely heavily on antibiotics and other drugs to prevent bacterial infections in fish. Some antibiotics used in swai fish in Vietnam are prohibited in the U.S. because of the risk of antibiotic resistance.

As with any other type of seafood, exercise caution if you are allergic to seafood.

Tips for Consuming Swai

Swai has a mild flavor with a hint of sweetness similar to flounder, tilapia, and grouper. To avoid foodborne illness, ensure that the fish is thoroughly cooked. Fully cooked fish should not look translucent and should break apart easily.

Many people purchase frozen swai at home. When purchasing swai, check the label for the amount of water and salt added. Researchers recommend cooking fish at a temperature of at least 145 degrees Fahrenheit (63 degrees Celsius).

Environmental Concerns

Swai are typically raised in fish farms, which have harmful environmental effects. Fish farms in Vietnam do not have many regulations. Farmers are allowed to use an unrestricted amount of chemicals while farming swai fish. 

Fish certified by the Aquaculture Stewardship Council (ASC) is safer to consume than brands of frozen fish that are not. Antibiotics in swai can also increase the presence of harmful bacteria by making species more resistant to antibiotics over time.

Fish farms produce large amounts of waste that can also contaminate other waterways, potentially harming consumers and other fish species.

A Quick Review

Swai is a type of fish farmed in Vietnam. It’s available as an affordable frozen fish option in the United States. Swai is a great source of protein, micronutrients, and vitamins. However, it does not contain as many nutrients, such as omega-3 fatty acids, as other fish like salmon, haddock, and sardines.

When purchasing swai, look for fish certified by the ASC to ensure the fish you purchase follows standard fish farming safety practices.