restaurant where its tilefish was caught.
If the answer isn’t clear, choose a lower-mercury option such as salmon, trout, cod, or haddock.
## 5. Bigeye Tuna
Tuna is one of the most popular fish served in restaurants.
It’s found in sushi.
It’s served as a seared steak.
It’s placed in salads.
It’s used in sandwiches.
And it’s often considered a healthy, protein-rich choice.
But tuna isn’t one single species.
Different types of tuna can have dramatically different mercury levels.
Bigeye tuna, in particular, is a species that can contain relatively high mercury levels.
That’s especially relevant for people who eat tuna frequently.
A single meal isn’t necessarily the issue.
Repeated exposure is more important when considering mercury intake.
### What to choose instead
Ask what kind of tuna is being served.
If you’re eating sushi, you can also consider lower-mercury options such as salmon, depending on the restaurant and your personal dietary needs.
If you love tuna, variety matters.
Rather than eating the same high-mercury species repeatedly, rotate seafood choices.
## 6. Orange Roughy
Orange roughy is a mild, white-fleshed fish that has appeared on restaurant menus for decades.
It can be prepared in many different ways and doesn’t have an especially strong fish flavor.
But there are two important reasons to think twice before ordering it.
First, orange roughy can contain relatively high levels of mercury.
Second, the species has historically raised sustainability concerns because orange roughy can live for a very long time and mature relatively slowly.
Those characteristics can make populations vulnerable when fishing pressure is high.
### What to choose instead
Cod, haddock, pollock, or responsibly sourced trout can be useful alternatives.
If sustainability is important to you, ask the restaurant whether its seafood is responsibly sourced.
## 7. Imported Farmed Salmon of Unclear Origin
Now here’s a fish that may surprise people.
Salmon is often considered one of the best seafood choices.
And it can be.
Salmon is rich in omega-3 fatty acids and provides plenty of protein.
But the source still matters.
“Salmon” doesn’t tell you whether it is wild-caught or farmed, where it came from, or how it was produced.
Farmed salmon isn’t automatically bad.
In fact, responsibly managed aquaculture can be an important part of feeding a growing population.
The issue is transparency.
If a restaurant simply lists “salmon” without providing any sourcing information, diners may have difficulty knowing what they’re getting.
### What to choose instead
Don’t automatically reject farmed salmon.
Instead, ask the restaurant what type of salmon it serves and where it comes from.
If sustainability is a priority, look for restaurants that clearly explain their seafood sourcing.
## 8. Escolar
Escolar is one of the more unusual fish on this list.
It has a rich, buttery texture that some diners love.
But that richness comes from its naturally high concentration of certain indigestible wax esters.
For some people, eating escolar can cause gastrointestinal symptoms, including diarrhea and stomach discomfort.
That’s why escolar has earned a reputation as a fish diners should approach cautiously.
It may also appear under different names on menus, depending on the establishment.
### What to choose instead
If you’re looking for a rich, satisfying seafood dish, salmon is an obvious alternative.
You can also choose a milder white fish such as cod or haddock.
If a menu describes a fish as extremely buttery or oily and you aren’t familiar with the species, it’s reasonable to ask what you’re actually ordering.
## 9. Raw or Undercooked Fish of Uncertain Handling
This category isn’t about one species.
It’s about preparation.
Raw fish can be delicious.
Sushi, sashimi, ceviche, and rare seared fish are enjoyed around the world.
But raw or undercooked seafood carries different food-safety considerations from fully cooked fish.
Parasites and harmful microorganisms can be a concern.
Proper sourcing, freezing practices, refrigeration, handling, and preparation all matter.
That doesn’t mean every sushi restaurant is dangerous.
Reputable establishments have food-safety procedures specifically designed for raw seafood.
But if you’re eating somewhere that doesn’t appear to handle seafood carefully, it’s worth thinking twice.
### What to choose instead
Order fully cooked seafood if you’re uncertain about the restaurant’s handling practices.
Grilled salmon, baked cod, roasted trout, or thoroughly cooked shrimp can all be excellent choices.
Certain people should be especially cautious about raw or undercooked seafood, including pregnant individ
