7 Unhealthy Fast-Food Fish Sandwiches, According to Dietitians

When you hit the drive-thru, the options are pretty endless: burgers, fried chicken sandwiches and tenders, and of course: fish sandwiches. And while you may think these are a healthier option than other proteins, there are plenty of unhealthy fast-food fish sandwiches to stay away from.

"Fish is generally a lean, high-quality source of protein," says Roxana Ehsani, MS, RD, CSSD, LDN, a registered dietitian in Miami, Florida. "It's how the fish is prepared that makes it unhealthy. Once you add breadcrumbs to it (which are made from refined grains and may be high in sodium), and deep fried patty (deep frying it really increases the total fat content of the sandwich), it's no longer 'healthy'."

Not only is the fish patty high in fat and sodium, what the restaurant may add to the sandwich can also be high in sodium and fat. "Fish sandwiches typically also have tartar sauce or mayo added, which is high in unhealthy saturated fat," adds Ehsani. "Some sandwiches might also have cheese added too, which can be add more saturated fat and sodium."

Finally, the bun is less than stellar nutrition-wise. "The bun is typically made from refined flour, not whole wheat flour, therefore lacking in fiber," says Ehsani. "Some are even made using a brioche bun, which is high in total fat."

Here are 7 of the most unhealthy fast-food fish sandwiches, according to dietitians. Plus, the healthiest fish sandwich you should pick instead.

Burger King Big Fish

Per sandwich: 510 calories, 28 g fat (4.5 g saturated fat, 0 g trans fat), 1,180 mg sodium, 51 g carbs (2 g fiber, 7 g sugar), 16 g protein

"It's sky-high in sodium, packing 1,180 milligrams per sandwich," says Ehsani. "It's also quite high in fat, with almost half of its calories coming from fat."

11 Healthiest Fast Food Burgers, According to Dietitians

Dairy Queen Wild Alaskan Fish Sandwich

Per sandwich: 420 calories, 16 g fat (3 g saturated fat, 0 g trans fat), 960 mg sodium, 50 g carbs (1 g fiber, 7 g sugar), 17 g protein

"This option only has one gram of fiber and not much protein," says Amber Pankonin, MS, RD, LMNT, CEC, registered dietitian and certified executive chef.

Wendy's Crispy Panko Fish Sandwich

wendy's wild-caught alaskan fish sandwich — Courtesy of Wendy's

Per sandwich: 520 calories, 25 g fat (6 g saturated fat, 0 g trans fat), 1,240 mg sodium, 51 g carbs (2 g fiber, 5 g sugar), 10 g protein

"It's really high in sodium, hitting over 1,200 milligrams, so this would be off limits for anyone with high blood pressure or diabetes," says Ehsani. "It's also quite high in saturated fat compared to others, hitting six grams of saturated fat, which the American Heart Association recommends limiting to 5-6% of your daily calories."

The Wendy's Breakfast Menu—Ranked by Nutrition!

Sonic Fish Sandwich

Per sandwich: 540 calories, 27 g fat (9 g saturated fat, 0 g trans fat), 1,240 mg sodium, 57 g carbs (4 g fiber, 10 g sugar), 18 g protein

"This option is high in calories, total fat, and sodium," says Pankonin.

Arby's Crispy Fish Sandwich

Arby's chicken sandwich — Courtesy of Arby's

Per sandwich: 570 calories, 25 g fat (4 g saturated fat, 0 g trans fat), 990 mg sodium, 65 g carbs (3 g fiber, 9 g sugar), 20 g protein

"It's pretty high in total carbs compared to other sandwiches, and unfortunately it's mainly coming from refined flour (not the good type of carbs)," says Ehsani. "It also packs 9 grams of sugar (higher than most), maybe from the bread or fillings. Plus, it is quite high in sodium, almost hitting 1,000mg.

Popeyes Cajun Flounder Sandwich

Per sandwich: 670 calories, 36 g fat (9 g saturated fat, 0 g trans fat), 1,960 mg sodium, 65 g carbs (4 g fiber, 9 g sugar), 25 g protein

"Yikes, this one is super high in total calories, high in total fat, high in saturated fat, and super high in sodium, almost hitting 2,000mg of sodium just in 1 sandwich (daily recommendations are no more than 2,300mg of sodium)," says Ehsani. "I would recommend most people to just avoid this one."

Jack in the Box Fish Sandwich

jack in the box deluxe fish sandwich — Jack in the Box/Facebook

Per sandwich: 410 calories, 19 g fat (3 g saturated fat, 0 g trans fat), 900 mg sodium, 45 g carbs (2 g fiber, 4 g sugar), 16 g protein

"This one is not the worst options, but the fact that it's hitting 900 mg of sodium per sandwich also doesn't make it the best option," says Ehsani.

So which fast-food fish sandwich should you pick instead? A McDonald's Filet-O-Fish

Per sandwich: 390 calories, 19 g fat (4 g saturated fat, 0 g trans fat), 580 mg sodium, 39 g carbs (2 g fiber, 5 g sugar), 16 g protein

"It's quite lower in calories compared to other fish sandwiches available," says Ehsani. "It does contain sodium, but doesn't break your daily allotted amount compared to other sandwiches on the list. The fish they are using is wild-caught Alaska pollock, which is a sustainable sourced fishery." In fact, McDonald's Filet-O-Fish made our list of the best main menu items at the fast-food chain.

Adds Pankonin, "Compared to the list above, this option is lower in calories, total fat, and sodium. One option (to make it healthier) could be to eliminate the cheese, which would further reduce calories, fat, and sodium."