Catfish are a type of white fish that can live in both freshwater and saltwater. While you might associate them with Creole and Cajun cuisine, there are actually thousands of types of catfish that are prepared around the world in all kinds of ways. These fish are known for being rich in vitamins, minerals and omega fatty acids.

Catfish Around the World

Catfish are eaten all over the world, including North America, Asia, Europe and Africa. Although the many species of catfish can vary considerably, it’s generally considered to be an affordable, adaptable fish regardless of where it’s found.

In North America, the channel catfish, native to the Mississippi River, is one of the most commonly consumed types. Americans consume 15 pounds of seafood per year on average. Over half a pound of this amount is farmed U.S. catfish. Catfish in America is consumed in a variety of forms, from deep-fried to blackened or integrated into a stew.

Regardless of the type of catfish, these fish are considered omnivorous, eating plants, insects, shellfish, other fish and even small land mammals or reptiles. This diverse diet means that there is a difference in nutrition between farmed and wild catfish. It also means that, as predators, catfish have the potential to grow into quite large fish. Catfish are actually considered to be the largest freshwater fish in Europe.

Catfish Nutrition Facts

Catfish are a good source of protein, with 49 percent of the daily value in one fillet (about 159 grams). Each 159-gram serving of channel catfish also has the following vitamins and minerals:

• 10 percent of the daily value (DV) for vitamin E
• 38 percent of the DV for thiamine (vitamin B1)
• 7 percent of the DV for riboflavin (vitamin B2)
• 18 percent of the DV for niacin (vitamin B3)
• 10 percent of the DV for pantothenic acid (vitamin B5)
• 15 percent of the DV for vitamin B6
• 65 percent of the DV for vitamin B12
• 8 percent of the DV for copper
• 9 percent of the DV for magnesium
• 32 percent of the DV for phosphorus
• 14 percent of the DV for potassium
• 29 percent of the DV for selenium
• 8 percent of the DV for zinc

Catfish also have small amounts (between 1 and 4 percent) of most other essential vitamins and minerals, including vitamin A, folate, vitamin C, calcium, iron and manganese. They also contain other nutrients, like choline and are good sources of healthy, essential fats. Catfish have both omega-3 and omega-6 fatty acids.

Farmed vs. Wild Catfish

Like many other creatures, catfish nutrition can differ based on whether they’re farmed or wild. The protein and minerals in both of these types of catfish are roughly the same. However, the vitamin content has some major differences. There’s 199 percent of the DV for vitamin D in wild catfish per one filet, compared to none in farmed catfish. However, there’s only 22 percent of the DV for thiamine (vitamin B1) in the same quantity of wild catfish, compared to the 38 percent in farmed catfish.

There are also less omega-6 fatty acids in wild catfish and more omega-3 fatty acids. This is actually a good thing, since most Western diets are already rich in omega-6 fatty acids, and high omega-3 content is actually one of the main health benefits of eating fish. This means that eating wild-caught catfish can be better for you as it can help you maintain a healthy, low ratio of omega-6 to omega-3 fatty acids.

Catfish Health Benefits

Catfish’s benefits come from its nutrients. While catfish isn’t considered a fatty fish like salmon, it’s still a good source of omega fatty acids. In particular, omega-3 fatty acids, like eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are good for your brain, heart, immune system and eyes.

Catfish is also a good source of vitamin B12, a nutrient that is typically only found in animal products. This nutrient is important for your health as it helps your body make DNA and keeps your nerve and blood cells functioning properly.

If you like to eat wild catfish, this fish is an excellent source of vitamin D, which isn’t found in too many foods naturally. This nutrient is important for your bones because it helps your body absorb calcium. It also helps maintain the function of your immune system and regulates cellular growth throughout your body.

In general, catfish is good for your health as it’s filled with different nutrients. However, if you’re pregnant or breastfeeding, you may want to select farmed catfish over wild catfish. This is because heavy metals, like mercury, have sometimes been found in wild catfish.

Read more: 9 Excuses to Eat More Seafood (Hint: It Can Make You Happy!)

Heavy Metals in Catfish

Traditionally, catfish has been considered to be a fish that is low in mercury. In fact, the U.S. Food and Drug Administration has recommended that up to 12 ounces of low-mercury fish and shellfish be consumed each week. They specifically refer to salmon, canned light tuna, pollock, shrimp and catfish as examples, while advising people to avoid large predatory fish. Catfish is listed as one of the ‘best choices’ of fish you could consume.

Catfish that are farmed are likely only allowed to grow up to a certain point. They’re also unlikely to display particularly predatorial behaviours, given how farmed fish are usually raised. However, wild-caught catfish, which can become very large, will increasingly consume bigger prey as they age. Bigger fish tend to be the ones that accumulate mercury and other heavy metals in their bodies.

Several studies, including a 2014 study in the Journal Chemosphere and a 2013 study in the Journal of the Asiatic Society of Bangladesh, Science have examined catfish accumulation of heavy metals in catfish. Excessive amounts of mercury, copper, cadmium, chromium and lead have been found in wild catfish throughout Europe and Asia.

If consumed too frequently, these heavy metals can cause neurological problems and organ damage. This means that if you’re specifically seeking fish low in mercury and other heavy metals, the smaller, farmed variety of catfish may be a safer option.