The 10 unhealthiest fast-food french fries in America

• Calories: 350 kcal (18% DV)
• Total fat: 14 g (18% DV)
• Saturated fat: 1.5 g (8% DV)
• Sodium: 650 mg (28% DV)
• Score (avg. of calories, saturated fat, sodium): 18%

Compared with the rest of this list, Culver's crinkle-cut fries are a relatively tame side to the calorie bomb that is the ButterBurger, with 350 calories and just 1.5 grams of saturated fat in a medium serving. Culver's potatoes are grown in the Pacific Northwest and cooked to order in canola oil. The 650 mg of sodium, however, is where these otherwise innocent-looking fries start to make their case for inclusion.

• Calories: 370 kcal (18% DV)
• Total fat: 22 g (28% DV)
• Saturated fat: 3 g (15% DV)
• Sodium: 790 mg (34% DV)
• Score (avg. of calories, saturated fat, sodium): 22%

Sonic's Groovy Fries have lots of ridges, which means plenty of nooks and crannies for salt and grease to settle into. A medium serving has 370 calories and 22 grams of fat, while the 790 mg of sodium makes this more than just a fun shape to dip into ketchup. And that's only if you restrain yourself from adding extra toppings like melted cheese or chili, which can nearly double the calories, fat, and sodium, pushing them into territory that's heavy for a main, let alone a side.

• Calories: 450 kcal (22% DV)
• Total fat: 21 g (27% DV)
• Saturated fat: 2 g (10% DV)
• Sodium: 820 mg (36% DV)
• Score (avg. of calories, saturated fat, sodium): 23%

Jack in the Box's medium fries are creeping into meal territory at 450 calories, with 21 grams of fat and 820 mg of sodium to go with them. The relatively low 2 grams of saturated fat is a small consolation, but these are still a lot of calories for something most people order as the supporting act.

• Calories: 320 kcal (16% DV)
• Total fat: 15 g (19% DV)
• Saturated fat: 2 g (10% DV)
• Sodium: 1,100 mg (48% DV)
• Score (avg. of calories, saturated fat, sodium): 25%

KFC's Secret Recipe Fries are the oddball of this bunch. The fries are coated and seasoned with KFC's signature blend, giving them a little more going on than your standard salted fry. At 320 calories, they actually have one of the lowest totals on the list, but the sodium level, at 1,100 mg, tells a very different story.

• Calories: 400 kcal (20% DV)
• Total fat: 19 g (24% DV)
• Saturated fat: 4 g (20% DV)
• Sodium: 800 mg (35% DV)
• Score (avg. of calories, saturated fat, sodium): 25%

Hardee's doesn't need a particularly complicated fry to rack up some serious numbers. Its medium fries reach 400 calories and 19 grams of fat, while 800 mg of sodium means the humble side dish is already responsible for a sizable chunk of a day's sodium before the burger even enters the picture.

• Calories: 420 kcal (21% DV)
• Total fat: 21 g (27% DV)
• Saturated fat: 3.5 g (18% DV)
• Sodium: 850 mg (37% DV)
• Score (avg. of calories, saturated fat, sodium): 25%

Carl's Jr. calls these Natural-Cut Fries, but there's nothing particularly natural about 420 calories, 21 grams of fat, and 850 mg of sodium in a medium serving. The fries also manage to edge out several higher-calorie options on sodium, making them a surprisingly salty addition to an already indulgent fast-food meal.

• Calories: 470 kcal (24% DV)
• Total fat: 22 g (28% DV)
• Saturated fat: 4.5 g (22% DV)
• Sodium: 740 mg (32% DV)
• Score (avg. of calories, saturated fat, sodium): 26%

In 2013, Shake Shack tried to make its fries better and replaced its frozen crinkle-cut fries with thinner, hand-cut potatoes. Customers hated them, and within a year, the New York burger chain brought back its frozen crinkle-cut fries. They're fried in soybean oil, and a regular serving has 470 calories and 22 grams of fat. They're not the saltiest fries here, but 740 mg of sodium is still a lot for something whose main job is to sit next to your burger.

• Calories: 370 kcal (18% DV)
• Total fat: 14 g (18% DV)
• Saturated fat: 5 g (25% DV)
• Sodium: 870 mg (38% DV)
• Score (avg. of calories, saturated fat, sodium): 27%

Smashburger's regular fries don't look particularly outrageous on the calorie front at 370 calories, and their 14 grams of fat is actually fairly restrained compared with some of the competition. The problem is the combination of 5 grams of saturated fat and 870 mg of sodium, giving this relatively modest serving a much less innocent nutritional profile.

• Calories: 450 kcal (22% DV)
• Total fat: 24 g (31% DV)
• Saturated fat: 9 g (45% DV)
• Sodium: 540 mg (23% DV)
• Score (avg. of calories, saturated fat, sodium): 30%

Steak 'n Shake's golden fries disguise their worrying nutritional value with their deceptively thin form. The chain switched to cooking its fries in 100% beef tallow, which could explain how they end up being the second unhealthiest on our list. A medium serving has 450 calories and 24 grams of fat, including 9 grams of saturated fat, the highest saturated-fat count on this list. Add 540 mg of sodium, and these fries have plenty going on before you even get to the Steakburger and milkshake.

• Calories: 953 kcal (48% DV)
• Total fat: 41 g (53% DV)
• Saturated fat: 7 g (35% DV)
• Sodium: 962 mg (42% DV)
• Score (avg. of calories, saturated fat, sodium): 42%

Five Guys is generous with its fries, to put it mildly. The chain uses fresh-cut potatoes that are cooked in peanut oil, and even the regular serving is famously large enough to make you wonder why you ordered a burger too. That portion comes with 953 calories and 41 grams of fat, including 7 grams of saturated fat, while the 962 mg of sodium is almost as much as you'd expect from an entire meal.

Hungry for more stories about the healthiness (or unhealthiness) of your favorite fast-food menu items?

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