10 Fish You May Want to Think Twice About Ordering at a Restaurant—and What to Choose Instead
Ordering fish at a restaurant often feels like one of the healthiest decisions you can make.
You sit down, scan the menu, and see grilled salmon, tuna steaks, fried seafood, snapper, swordfish, or some beautifully prepared daily catch. Compared with a heavy burger or a rich pasta dish, fish can seem like the obvious choice.
But there’s another side to ordering seafood that many diners don’t consider.
The question isn’t simply whether a fish tastes good.
It can also be about where the fish came from, how it was caught, how it was stored, how frequently you eat it, whether it is sustainably sourced, and whether certain species naturally contain higher levels of contaminants such as mercury.
That doesn’t mean fish is unhealthy.
Far from it.
Fish can provide high-quality protein, omega-3 fatty acids, vitamin D, vitamin B12, selenium, and other valuable nutrients. For many people, seafood can be an excellent part of a balanced diet.
The problem is that not every fish is equally appropriate for every diner or every situation.
Some species are relatively high in mercury.
Some restaurant dishes may be heavily fried or covered in rich sauces.
Some menu names are vague enough that you don’t really know which species you’re ordering.
And some seafood choices raise sustainability concerns.
So rather than thinking of this as a list of fish that are “bad,” it’s more useful to think of it as a list of fish that may deserve extra attention when you’re eating out.
Here are 10 fish you may want to think twice about—and some alternatives that can make ordering seafood easier.
## 1. Swordfish
Swordfish is popular for a reason.
Its thick, meaty texture makes it feel more like a steak than a delicate fish fillet. It’s often grilled, seared, or served with vegetables and a lemon-based sauce.
But swordfish is also one of the species that can contain relatively high levels of mercury.
Mercury accumulates in fish over time, particularly in larger predatory species that eat other fish.
Swordfish are large predators and can therefore accumulate more mercury than many smaller fish.
For an occasional restaurant meal, this doesn’t automatically mean you need to panic.
But people who are pregnant, trying to become pregnant, breastfeeding, or feeding young children should pay particularly close attention to official seafood guidance concerning high-mercury species.
### What to choose instead
Try salmon, trout, sardines, or another lower-mercury seafood option.
These alternatives can provide valuable nutrients while generally presenting less concern about mercury exposure.
## 2. Shark
Shark can appear on menus in some coastal restaurants, seafood establishments, and specialty eateries.
Like swordfish, sharks are large predatory fish.
Because they occupy a high position in the marine food chain and can live for years, some shark species can accumulate substantial amounts of mercury.
Another issue is sustainability.
Shark populations can be vulnerable to overfishing, and different species face very different conservation circumstances.
That means the question isn’t simply whether shark tastes good.
It is also whether you know what species you’re eating and where it came from.
### What to choose instead
If you’re looking for a firm, meaty fish, ask about sustainably sourced salmon, mahi-mahi, or responsibly sourced cod.
And if shark is on the menu, don’t be afraid to ask the restaurant what species it serves and where the seafood was sourced.
## 3. King Mackerel
Mackerel can be confusing because the word covers several different fish.
Some types of mackerel are nutritious choices and can be excellent sources of omega-3 fatty acids.
King mackerel, however, is a high-mercury species and is generally placed among fish that people should limit or avoid depending on their circumstances.
This is an excellent example of why the exact species matters.
A menu that simply says “mackerel” doesn’t necessarily give diners enough information to make an informed decision.
If you’re concerned about mercury, ask which type of mackerel the restaurant serves.
### What to choose instead
Atlantic mackerel is generally a different story and can be a nutritious choice when appropriately sourced.
Salmon and sardines are also excellent alternatives if you’re specifically looking for omega-3-rich seafood.
## 4. Tilefish
Tilefish has a mild flavor and firm texture, which can make it attractive to restaurant chefs.
But “tilefish” is another name that requires caution because mercury levels can vary substantially depending on where the fish was caught.
Certain tilefish from the Gulf of Mexico have historically been associated with particularly high mercury levels.
That doesn’t mean every fish labeled tilefish is identical.
Geographic origin matters.
This is a good reminder that seafood safety isn’t always as simple as memorizing a list of species.
### What to choose instead
Ask the
