Seafood can be one of the most nutritious options on a restaurant menu. Many fish provide high-quality protein, beneficial omega-3 fatty acids, vitamins, and minerals that support overall health.
However, not every seafood choice is the same.
Some species naturally contain higher levels of mercury. Others may be harvested from overfished populations or are sometimes mislabeled in the seafood supply chain. Farming and sustainability practices can also vary depending on where and how the fish was produced.
That doesn’t mean you should avoid seafood altogether. Instead, making informed choices can help you enjoy its nutritional benefits while considering health and environmental factors.
Here are ten types of fish that may be worth thinking about before ordering, along with practical alternatives.
1. Swordfish
Swordfish is known for its firm texture and rich flavor, making it a popular menu item.
However, it is also one of the fish species that can contain relatively high levels of mercury because it is a large, long-lived predator.
Many public health agencies recommend that young children and people who are pregnant or breastfeeding limit or avoid high-mercury fish.
For many other adults, occasional consumption may still fit within a balanced diet.
Alternative choices:
- Salmon
- Rainbow trout
- Sardines
2. King Mackerel
King mackerel is another large predatory fish that may accumulate higher mercury levels over time.
It’s important not to confuse king mackerel with Atlantic or smaller mackerel species, which generally have different nutritional profiles and lower mercury levels.
Alternative choices:
- Atlantic mackerel
- Herring
- Anchovies
3. Shark
Although not commonly served everywhere, shark appears on some restaurant menus around the world.
Because sharks are long-lived predators, they may contain higher concentrations of mercury than many smaller fish species.
Availability also varies significantly by region.
4. Tilefish (From Certain Regions)
Tilefish can be an excellent source of protein, but mercury levels differ depending on where the fish is caught.
Some regional populations have higher mercury concentrations than others.
Restaurant staff or suppliers may sometimes be able to identify the source of their seafood.
5. Orange Roughy
Orange roughy became popular because of its mild taste.
One concern often discussed is sustainability.
This species grows slowly and may live for many decades, making some populations more vulnerable to overfishing.
Choosing seafood from well-managed fisheries helps support long-term conservation efforts.
6. Imported Farmed Shrimp
Shrimp itself is enjoyed worldwide and can absolutely be part of a balanced diet.
However, farming standards vary between countries.
Some imported shrimp may come from operations with different environmental or quality-control practices than others.
Many restaurants now identify sustainably sourced shrimp on their menus.
When available, asking about sourcing can help you make an informed decision.
7. Bluefin Tuna
Bluefin tuna is highly valued for its rich flavor and is commonly served in certain restaurants.
Some bluefin populations have experienced significant fishing pressure over the years, leading to conservation concerns in various parts of the world.
Sustainability certifications or responsible sourcing programs can help identify seafood from better-managed fisheries.
8. Chilean Sea Bass
Despite its popularity, Chilean sea bass has faced sustainability challenges in some fisheries.
Fortunately, improvements in fishery management have occurred in several regions.
If sustainability is important to you, consider asking whether the restaurant sources certified products.
9. Eel
Eel appears in many traditional cuisines and is appreciated for its unique flavor.
Some eel populations have declined significantly due to habitat loss, migration barriers, and other environmental pressures.
Availability and sustainability vary depending on the species and region.
10. Certain Fish Sold Under Generic Names
Sometimes restaurant menus simply list:
- White fish
- Market fish
- Catch of the day
These descriptions aren’t necessarily problematic.
However, they may provide very little information about the actual species being served.
If you’re concerned about sustainability, allergens, or mercury, don’t hesitate to ask:
- What species is it?
- Where was it caught?
- Is it wild or farm-raised?
Most restaurants are happy to answer if they have that information.
Understanding Mercury
Mercury occurs naturally in the environment but can accumulate in larger predatory fish over time.
Generally speaking:
Lower-mercury choices often include:
- Salmon
- Sardines
- Anchovies
- Trout
- Herring
- Pollock
Higher-mercury species often include:
- Swordfish
- Shark
- King mackerel
- Certain tilefish
National health authorities provide guidance on recommended seafood choices for different groups, including pregnant individuals and young children.
Sustainability Matters Too
Choosing seafood from responsibly managed fisheries helps protect marine ecosystems.
Several organizations evaluate fisheries and aquaculture practices based on sustainability standards.
Some restaurants display certifications or sourcing information on their menus.
If sustainability is important to you, asking questions is perfectly reasonable.
Seafood Mislabeling
Studies have shown that seafood substitution can occur in parts of the global supply chain.
For example, one species may occasionally be sold under the name of another.
Restaurants that work with reputable suppliers and provide transparent sourcing information help reduce this concern.
Healthy Fish to Consider More Often
Many seafood options combine good nutrition with relatively lower mercury levels.
These include:
Salmon
Rich in omega-3 fatty acids and widely recommended as part of a balanced diet.
Sardines
Small fish that provide calcium, vitamin D, and healthy fats.
Rainbow Trout
Often praised for its mild flavor and nutritional profile.
Herring
A traditional seafood choice rich in beneficial fats.
Pollock
Frequently used in seafood dishes and generally considered a lower-mercury option.
Atlantic Mackerel
Not to be confused with king mackerel, Atlantic mackerel provides omega-3 fats while typically containing much lower mercury levels.
Tips for Ordering Seafood at Restaurants
When dining out, consider asking a few simple questions:
- Is the fish wild-caught or farm-raised?
- Where was it sourced?
- Is it seasonal?
- Is it grilled, baked, or fried?
- Does the restaurant participate in sustainable seafood programs?
These questions can help you make choices that match your preferences.
Balance Is the Key
It’s important to remember that seafood remains an important part of many healthy eating patterns.
Rather than avoiding fish entirely, nutrition experts generally encourage variety.
Rotating different seafood choices allows you to enjoy a broad range of nutrients while reducing reliance on any single species.
Final Thoughts
Seafood offers many nutritional benefits, including high-quality protein and heart-healthy omega-3 fats. However, factors such as mercury levels, sustainability, and sourcing can vary between species.
Being informed doesn’t mean giving up your favorite seafood dishes—it simply means making thoughtful choices based on your health needs and personal values.
The next time you’re browsing a restaurant menu, taking a moment to consider the type of fish, where it came from, and how it was prepared can help you enjoy a meal that’s both delicious and well-informed.
As always, a balanced diet that includes a variety of nutrient-rich foods remains one of the best ways to support long-term health.