Ordering fish at a restaurant often feels like an easy decision. Compared with fried foods, burgers, or heavy dishes, seafood is commonly viewed as a lighter and nutritious option. A beautifully cooked fillet can provide plenty of protein, and many types of fish contain beneficial nutrients such as omega-3 fatty acids.

But there is more to choosing seafood than simply looking at the name on the menu.

Different fish species can vary considerably in mercury levels, environmental impact, population health, and farming or fishing practices. Some large predatory fish can accumulate more mercury because they eat other fish and live for many years. Other species may come from fisheries that have faced concerns about overfishing or habitat damage.

That doesn’t mean seafood should disappear from your menu.

In fact, fish can be an excellent part of a balanced diet. The better approach is to understand which choices may deserve more consideration and which alternatives can make ordering easier.

Here are ten seafood choices you may want to think about before ordering, along with some alternatives worth considering.

1. Swordfish

Swordfish is popular in restaurants because its firm texture holds up beautifully to grilling, roasting, and pan-searing.

However, swordfish is a large predatory fish, and larger, longer-lived fish can accumulate higher concentrations of mercury than many smaller species.

For people who eat seafood regularly, choosing lower-mercury fish more often can be a practical way to vary their diet.

Try instead: Salmon or trout can provide a flavorful alternative while generally being lower in mercury.

2. Shark

Shark may appear on some specialty seafood menus, but it is another large predator that can contain relatively high mercury levels.

There is also a conservation consideration. Shark populations and fishing pressures vary significantly by species and location, so the environmental story isn’t always straightforward.

If you’re simply looking for a nutritious seafood meal, there are plenty of alternatives that don’t require as much uncertainty.

Try instead: Salmon, trout, or another clearly identified fish from a well-managed source.

3. King Mackerel

Mackerel can be an excellent seafood choice, but the word “mackerel” covers several different species.

King mackerel is one variety that can contain relatively high levels of mercury. That’s important because someone who thinks they’re choosing a healthy fish may not realize that the specific species makes a difference.

Don’t assume every type of mackerel has the same nutritional and mercury profile.

Try instead: Atlantic mackerel is generally a lower-mercury option, while salmon is another popular alternative.

4. Orange Roughy

Orange roughy has a mild taste and delicate texture, which can make it appealing to diners who prefer a subtle white fish.

The concern is less about the flavor and more about the biology of the species. Orange roughy can live for many decades and mature slowly. Fish with these characteristics can be particularly vulnerable to heavy fishing pressure because populations may take a long time to recover.

Try instead: Cod or haddock can offer a similar mild, flaky experience, depending on the source.

5. Tilefish

Tilefish is another species that deserves some attention because mercury levels can vary considerably depending on where the fish was caught.

This is a good example of why the name of the fish alone doesn’t always tell the whole story. Geographic origin can influence the safety considerations associated with certain seafood.

When a restaurant provides sourcing information, it becomes much easier to make an informed choice.

Try instead: Ask about the origin of the tilefish or select a lower-mercury seafood option.

6. Bigeye Tuna

Tuna is one of the most common seafood choices on restaurant menus, appearing in everything from sushi and poke bowls to steaks and salads.

However, different tuna species have different mercury levels. Bigeye tuna can contain relatively high mercury concentrations, making frequent consumption something worth considering.

That doesn’t mean tuna has to be completely avoided. The important factor is variety and knowing which type you’re eating.

Try instead: Salmon, sardines, or other lower-mercury seafood can provide variety.

7. Seafood With Unclear Farmed Salmon Sources

Salmon itself is generally considered a nutritious choice and is widely appreciated for its protein and omega-3 content.

The question can sometimes be where it comes from.

Farmed and wild salmon are produced differently, and farming practices can vary by region and producer. Restaurants don’t always provide enough information on their menus to tell diners exactly how their salmon was raised.

If sourcing matters to you, there’s nothing wrong with asking.

Try instead: Choose restaurants that clearly identify whether their salmon is wild-caught or farmed and, when possible, provide information about its origin.

8. Farmed Shrimp

Shrimp isn’t technically a fish, but it appears on so many seafood menus that it deserves a place in this conversation.

Farmed shrimp can be produced under very different conditions around the world. Depending on the region and operation, environmental concerns can include habitat conversion, water management, and other production practices.

The important point is that “farmed” doesn’t automatically mean bad, just as “wild” doesn’t automatically mean perfect.

Try instead: Ask where the shrimp was sourced and whether the restaurant has information about its supplier or production method.

9. Cod From an Unclear Source

Cod has a reputation as a simple, versatile restaurant fish. It can be baked, grilled, fried, or paired with almost any seasoning.

But cod populations aren’t identical everywhere.

The sustainability of a particular cod choice can depend on the fishery, geographic location, management practices, and condition of the stock.

Therefore, seeing “cod” on a menu doesn’t automatically tell you whether the fish came from a well-managed source.

Try instead: Ask where the cod was caught or look for restaurants that provide detailed seafood sourcing information.

10. “Market Fish” With No Additional Details

Perhaps the biggest warning sign isn’t a particular species at all.

It’s a menu that doesn’t tell you what you’re eating.

Terms such as “market fish,” “fresh catch,” or simply “white fish” can sound appealing, but they don’t necessarily identify the species, origin, or production method.

Without that information, it’s harder for diners to consider mercury levels, conservation concerns, or sourcing practices.

Try instead: Choose a restaurant that clearly identifies its seafood and is willing to answer questions about where it comes from.

So What Fish Should You Order?

Fortunately, there are plenty of seafood options that can fit into a healthy and varied diet.

Salmon

Salmon is one of the most popular choices for good reason. It provides high-quality protein and omega-3 fatty acids and works well with many different cooking styles.

Sardines

Sardines are small fish that are generally lower in mercury than many large predatory species. They’re also nutrient-dense and can be enjoyed in salads, sandwiches, or as part of a larger meal.

Trout

Trout is another versatile choice that can work well grilled, baked, or pan-seared. Depending on the species and source, it can be a good alternative to larger fish.

Atlantic Mackerel

Don’t confuse all mackerel species. Atlantic mackerel is generally considered a lower-mercury option than king mackerel and can be a flavorful source of omega-3 fats.

Other Clearly Sourced Seafood

One of the simplest strategies is to favor restaurants that tell you where their seafood comes from.

Good sourcing information gives customers the ability to make decisions based on their own priorities, whether those involve nutrition, sustainability, or both.

Ask Questions Before Ordering

You don’t need to become a seafood expert before visiting a restaurant.

A few simple questions can provide useful information.

You might ask:

“What species of fish is this?”

“Where was it caught or raised?”

“Is it wild-caught or farmed?”

“Do you know the source of today’s seafood?”

A restaurant that takes its seafood program seriously will often have answers available.

Variety Is One of the Best Strategies

One of the biggest takeaways isn’t that you should permanently eliminate certain fish from your diet.

Instead, variety can be helpful.

Rather than eating the same high-mercury species repeatedly, rotate among different seafood options. If you eat fish often, favor lower-mercury choices more frequently and pay attention to guidance about mercury exposure.

For sustainability, look for restaurants and seafood suppliers that are transparent about sourcing and fisheries management.

There is rarely one perfect choice for every person or every situation.

Seafood Can Still Be a Great Choice

Reading about mercury, overfishing, farming practices, and environmental concerns can make seafood seem complicated.

But the solution isn’t necessarily to stop ordering fish.

A little awareness can make the process much easier.

The next time you open a restaurant menu, look beyond the attractive description of the dish. Consider the species, ask where it came from, and think about how frequently you eat that particular fish.

You don’t have to make every seafood decision perfectly.

You simply need enough information to make a thoughtful choice.

A nutritious meal can also be a responsible one, and sometimes the best choice on the menu isn’t the most expensive or exotic fish.

It’s the option you understand, enjoy, and feel comfortable ordering.

In the end, seafood is too diverse to put every species into one simple category. Some choices may deserve more caution, while others can be excellent additions to a balanced diet.

The goal isn’t to fear seafood. It’s to become a smarter seafood customer.