Things you should never order from a sushi restaurant

Sushi lovers can all agree that there's nothing else quite like it in the world. It's not just my opinion, but a popular one — the number of sushi restaurants in the Unites States has been growing steadily since the 1980s, with more than 3,000 sushi establishments now set up in America. I'd say that particular food group has quite the fan club. Still, before you sit down to enjoy your next sushi meal, it's important to know that not everything on the menu is a great choice. There are a few items you should never eat at a sushi restaurant, no matter what your server says.

Mackerel pike

Mackerel pike, also known as sanma, is a freshwater fish found in northern waters, and can be found in sushi restaurants as sashimi (raw fish sliced thin and served with shredded white radish or rice) or sunomono, which is also raw but served with a vinegar dressing. You also may find it seared, pressed, or fermented. No matter how it's served, registered dietitian Jackie Arnett Elnahar says you should always stay away from freshwater fish when ordering sushi, as they are more likely to have parasites. Though parasites are a risk you take any time you eat raw fish, that risk is much higher when the fish is coming from freshwater habitats.

Bluefin tuna

Bluefin tuna might not be harmful to you, but ordering it may do harm to the environment. Ryan Bigelow, program engagement manager for the Monterey Bay Aquarium Seafood Watch program, says bluefin tuna populations are depleted and still being overfished. Some environmental groups are petitioning the U.S. government to list them as endangered and attribute their decline largely to demand in sushi markets. Bluefin tuna, also known as maguro, is seen in many dishes at sushi restaurants, such as the all-popular rolls, but also often served alone. Since sushi is often named by the part of the fish, you'll also want to keep an eye out for the names akami (lean meat from the sides of the fish) and toro (the fatty part of the fish's belly). The toro is often broken up even farther into two parts called the otoro and the chutoro. Since there are three main types of tuna sold at sushi restaurants, you'll want to ask your server or chef what type of tuna they are using when you order. The other types often used are yellowfin tuna and bigeye tuna. "In international waters, the measures to help the bluefin populations recover and reduce the catch of threatened, endangered, and depleted species are ineffective," says Bigelow. You can do your part by making sure the bluefin isn't part of your dinner. "Look for albacore tuna belly (shiro maguro) instead," he advises.

Registered dietitian Jackie Arnett Elnahar says the mercury content of all tuna should take it off your menu if you're pregnant, trying to get pregnant, or breast feeding. (Some research shows light canned tuna in water is safe for these women, though there is not widespread scientific consensus. Playing it safe is probably a good idea.)

Crab

Author and chef Warren Bobrow warns sushi fans to stay away from crab, which is found in a variety of rolls and is often served alone or on a bed of rice. "There is a sickness in fresh crab that can make you very, very ill," he said. "Fortunately, most sushi bars serve surimi crab or pollack fish that has been dyed." The sickness Bobrow is referring to is shellfish poisoning, which can happen whether the meat is cooked or not. While it's true that sushi restaurants often serve imitation crab meat, the fish used to make imitation crab varies by provider, so it's difficult to evaluate comprehensively.

Salmon

Chef Hank Scrampton says sushi lovers should avoid salmon, a freshwater fish, because of its potential for parasites. "Freshwater fish are the most likely fish to carry parasites, which can be pretty gross, but most of the time they're killed by the freezing process," he said. "It's funny, a lot of people would say that they would never want to eat frozen fish, but nearly all of the sushi you get has been frozen, and that's a good thing. Kills off a lot of the bad stuff and keeps the fish tasting fresh."

If you just can't avoid salmon at your favorite sushi restaurant, ask your server if they can show you the logs for how long the fish was frozen and at what temperature. According to FDA regulations, fish must be frozen at -4 degrees Fahrenheit (colder than a typical home refrigerator) for at least a week to avoid parasites. Short of asking for the logs, you can just ask the server how long they usually freeze it and see what they say. It may feel like you're being a pain, but reputable sushi restaurants should be able to provide this information, and your health is worth the trouble.

Iceberg salads

Of all the food you might encounter at a sushi restaurant, you would probably assume the iceberg salad they sometimes serve on the side would be the safest bet, right? Wrong, according to chef Hank Scrampton. "If we're talking about takeout style sushi, I always tell people to be careful with those little iceberg salads they stick in the bag. I've seen them reused from people who dined in-house and didn't finish the salads," he said. "No joke, some places even have large plastic buckets where they just dump unused salads and dip back into them throughout the day and night."

Snapper

If you're a fan of ordering the snapper at your usual sushi dive, you're about to be disappointed. It's probably not actually snapper that you're eating. Rockefeller University's Dr. Mark Stoeckle, who helped out with DNA species testing for the Barcode of Life project, told Eater the best way to avoid fake red snapper is not to order it. In a 2013 study, true snapper was served less than 6 percent of the time it was ordered at restaurants. Save yourself the worry — and the money — and pick something else off the menu.

Eel

If you've ever had a dragon roll, you know the lure of eel in sushi restaurants is hard to resist. However, Ryan Bigelow, program engagement manager for the Monterey Bay Aquarium Seafood Watch program, says it should definitely be avoided. "Overall, eel ranks among the worst seafood choices from an environmental perspective," he said. "Due to its extreme popularity in sushi bars and the rise of sushi consumption around the world, high demand coupled with loss of habitat has driven wild eel populations to endangered statuses. Farms collect eels from the wild, further impacting stressed stocks." He recommends you check the menu for sablefish instead, which is an environmentally safe, but still tasty, swap.

White tuna

According to chef Hank Scrampton, white tuna is another fish you should watch out for: "White tuna is frequently swapped with a fish called escolar which is inferior." And escolar isn't just an inferior fish — it's a risky one to eat. Eating escolar can lead to serious digestive issues, including sudden and explosive diarrhea — which I think pretty much everyone would like to avoid. It's estimated that close to 59 percent of white tuna dishes served at restaurants are not actually white tuna.

Now that you know what to avoid, go out and enjoy a sushi dinner that's safe — both for you and for the environment. There's still plenty left on the menu to enjoy, I promise.

Anything deep-fried, like tempura

Hey, I love tempura as much as the next person in line at the local sushi restaurant, but sometimes I know I need to watch my habit. While this dish of battered and deep-fried seafood and vegetables is crunchy, greasy, and downright delicious, it's also loaded with saturated fat and needless calories. As with anything deep-fried, you may not be able to resist indulging a little, but don't go overboard. If, unlike me, you have some iron-clad willpower, skip the tempura altogether. Also beware of any dishes that call out "crunchy" as a descriptor as you're bound to receive some sneaky deep-fried element in it.

Instead, try ordering veggie-forward dishes. Since I love the maki rolls, I try to choose ones that contain protein as the primary protein source and a variety of other vegetables like mushrooms and carrots.

Anything with teriyaki sauce or Japanese mayo

While it may require a bit more vigilance to catch, try to avoid dishes that contain ingredients not traditionally part of Japanese cuisine. As far as that goes, the biggest culprits are often the accompanying sauces. Mayo, cream cheese, and sugary sauces like teriyaki are guilty! They add tons of extra calories and fat to meals that are otherwise fresh, flavorful, and nourishing. Steer clear.

Opt instead for sinus-clearing wasabi, a green Japanese horseradish that lends the perfect kick to your meal. Some studies have shown that it might have health benefits in addition to being a tasty condiment. Of course, you'd have to be at a pretty classy sushi joint in the U.S. to find real wasabi, as it's very rare. But even the common wasabi-like mixture is better than the other fatty sauces. Also, try enjoying bits of pickled ginger to clean your palate in between dishes and increase general immunity to illnesses.

Seaweed salad

If you maintain a gluten-free diet, beware that seaweed salads are made with soy sauce, which in addition to being high in sodium, isn't necessarily gluten-free. Sometimes artificial food coloring is also added to get yield a vibrant green color.

Since seaweed does have extensive nutritional benefits, you should order it with caution. Simply ask your waiter or waitress about what else is in the salad before ordering.

White rice

The amount of white rice consumed at a sushi restaurant is kind of mind-boggling and not particularly healthy. Even only eating a few maki rolls means having to take down loads of rice. As carbs increase your insulin and blood sugar levels, you should avoid eating large amounts of white rice.

Instead, try swapping out white rice for whole-grain brown rice in your rolls. Full of fiber and more filling than its counterpart, the brown version makes you fuller, naturally preventing you from bingeing.

Roe and quail egg

Roe and quail eggs is not a very healthy choice when eating out at a sushi restaurant. This dish is chock full of saturated fat and extra cholesterol, like regular chicken eggs. And since the eggs are consumed raw, there is also the added risk of salmonella.

Opt for typically healthier rolls such as avocado rolls, cucumber rolls, or California rolls. Or choose seafood rolls that are lower in mercury, like the ones that include salmon, crab, eel, or carp.

Soy sauce

Soy sauce is loaded with sodium, which can contribute to spikes in your blood pressure. While low-sodium versions contain about 25 percent less sodium, they're still pretty salty! Regular soy sauce contains about 900 milligrams of sodium per tablespoon serving. That's a lot!

If you must have this popular condiment with your sushi dishes, try to go easy.