Fast-food and fast-casual restaurants build their businesses — and their menus — around carb-loaded burgers, fries, sandwiches and burrito bowls. If you’re following the keto diet, or just trying to control your carb intake, you’re going to want to seek out the best low-carb alternatives.

Step one is to nix the bread or bun if you’re going for a traditional sandwich or burger — they can easily add 40 to 50 grams of carbs to your meal. “Ask for extra lettuce to wrap it in,” says Abby Langer, RD, of Abby Langer Nutrition in Toronto.

Skip the ketchup, relish and barbecue sauce, too — they’re typically high in carbs. “Sugary condiments are some of the sneakier sources where carbs might show up,” says Samantha Cassetty, RD, nutrition and weight loss expert with a virtual nutrition counseling practice based in New York City. And you’ll want to leave out the carb-heavy beans, rice and corn, too.

TRY THESE LOW-CARB FAST FOOD OPTIONS

Along with no-bun burgers and sandwiches, most of these restaurants offer salads that can be good low-carb options, with modifications. Make sure you choose a dressing that’s lower in carbs. Ranch, blue cheese and Italian tend to be lower carb than thousand island or fruit-flavored vinaigrettes.

“Stay away from fruit and be careful with salad dressing — that’s a typical source of hidden sugar. Depending on the one you get, there can be a few grams of added sugar in the dressing,” Cassetty says. Skip the croutons, too.

Instead, consider keeping dressings, Greek or Italian seasoning blends, lemon juice, and avocado oil on hand to enhance your salad. That way you can go with the lowest-carb option and add your own favorite flavors.

If you add protein to your salad, go with grilled meats over crispy. A salad with crispy chicken could easily add 18 grams of carbs, compared to its grilled counterpart.

At places like Chipotle and Taco Bell, Langer recommends blending guacamole and salsa and using that as a dressing.

For drinks, you’ll want to go with zero-carb water or unsweetened iced tea — and go for diet if you're a soda drinker. Be careful with coffee drinks — a medium iced latte from McDonald’s has 7 grams of carbs.

FOCUS ON HEALTHY LOW-CARB OPTIONS

Aim to do keto in the healthiest way possible. “That means reducing red meat and limiting processed meat,” Cassetty says. She recommends poultry, fish and eggs for proteins and avocados, olives and olive oil for fats.

Langer agrees, and points out that a Baconator without a bun or ketchup is still loaded with calories (760, to be exact). “Just because it’s low-carb doesn’t mean it’s healthy,” she says. “Keto done right means a lot of avocado, nuts and vegetables.”

And Cassetty says, “Sensible eating means going for a smaller burger and amping out your meal with non-starchy veggies like salad. That’s always going to be healthier than any triple-decker with cheese and bacon.”

6 fast food restaurants with low-carb and keto-friendly options

Here are some top keto-friendly and low-carb options at popular fast-food and fast-casual chains. If you're going for a bunless burger or sandwich, don't forget to ask for it in a lettuce wrap or ask for extra lettuce on the side to make your own.

1. McDONALDS

Use the McDonalds nutrition calculator to edit the ingredients and customize the nutrition information for any of their menu items.

Artisan Grilled Chicken Sandwic h, no bun, no ketchup: 2g carbs

2g carbs Bacon Ranch Grilled Chicken Salad, no dressing : 8g carbs (the Newman’s Own Ranch Dressing adds 8g carbs)

: 8g carbs (the Newman’s Own Ranch Dressing adds 8g carbs) Quarter Pounder, no bun, ketchup or cheese: 1 carb

1 carb Egg McMuffin and most other breakfast sandwiches, no bread: 3-4g carbs

2. BURGER KING

The site No Bun Please outlines a lot of options for low-carb eating at Burger King.

Whopper Jr., plain with no bun: 0g carbs

0g carbs Grilled Chicken Sandwich, no bun: 1g carbs

1g carbs Sausage, Egg & Cheese Croissanwich and most other breakfast sandwiches, no bread: 1-4g carbs

3. WENDY’S

The site Hip 2 Keto lists low-carb options at Wendy’s and breaks out the nutrition info on some toppings and sides so you can see how many carbs they add.

Grilled Chicken Sandwich, no bun or sauce: 2g carbs

2g carbs Caesar side salad, no croutons with lemon garlic caesar dressing: 4 carbs

4. TACO BELL

Customize your meal with Taco Bell’s nutrition calculator to see exactly how many carbs you’re getting.

Chicken Power Menu Bowl, no beans, rice, or sour cream: 6g carbs

6g carbs Shredded Chicken Burrito, no rice or tortilla: 2g carbs

2g carbs Grande Scrambler Burrito, no potato or tortilla: 7g carbs

Chipotle’s nutrition calculator lets you add and remove ingredients to customize your meal and your carbs.

Keto Salad Bowl with carnitas, guacamole, tomatillo-red chili salsa, and cheese: 14g carbs

14g carbs Carnitas Burrito Bowl, no rice or beans, with fajita vegetables, cheese, and romaine lettuce: 7g carbs

To see the carb counts for many of Panera Bread’s options once you remove things like bread and croutons, check out No Bun Please.

Caesar Salad with Chicken, no croutons: 7g carbs

7g carbs Heritage Ham & Swiss sandwich, no bread: 3g carbs

3g carbs Bacon, Egg, and Cheese and most other breakfast sandwiches, no bread: 1-2g carbs

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