Craving an easy lunch? Maybe the green and yellow lights of Subway are beckoning you? 

When you’re on the go and need an inexpensive, filling lunch, sometimes the healthiest places to stop are fast-food restaurants with flexibility, experts previously told USA TODAY. Customizable menus allow you to control what’s in your meal and, most importantly, load up on the veggies. 

Subway is a prime example. It's got classics like the Cold Cut Combo and Veggie Delight, but the sky’s the limit when you build your own. 

But, which decisions impact your health the most? Here’s what we found out.

Which bread is the healthiest at Subway?

Generally, Subway’s “Hearty Multigrain” is going to be the healthiest choice. Compared to the Artisan Italian, Italian Herbs and Cheese, Jalapeño and Cheddar, Flatbreads and Wraps, it’s a lower calorie option and notably has a touch more fiber and protein. 

But it’s not a significant enough difference that choosing a different bread is going make or break your health, says Kat Benson, a registered dietitian with Top Nutrition Coaching. 

“Sometimes people can miss the forest for the trees in being so hyper-focused on which bread to choose rather than the rest of (their diet) that’s going to make a larger impact on their health," Benson says.

A more mindful route might be asking yourself what you want to get out of this meal, Benson says. If you’re not super hungry but know you should eat before you get "hangry," choose a lighter option like a flatbread. If you need something with a little more staying power, opt for the Hearty Multigrain Bread.

But if you’re more into the Artisan Italian Bread or the Jalapeño Cheddar Bread, you shouldn’t feel guilty about making that choice, Benson says. 

“That stress can cause more issues overall,” she says.

Bread is often demonized in diet culture spaces – we crave the easily digestible carbohydrate when we’re most hungry but as an individual food, it’s not balanced like a full meal of carbs, protein and fat. 

But bread certainly has a place in a healthy diet, Benson says, and can even provide important nutrients like fiber. It can be a vehicle for other nutrients – like the protein, fat and fiber found in the rest of the sandwich – and it’s an important staple across many cultures.

Is Flatbread healthier at Subway?

The Flatbread option at Subway is lower in calories and carbohydrates, but it also has about half the amount of protein. You’re getting fewer carbs because there’s less bread. It has less sodium as well, which can be a good option for someone with medical nutrition therapy needs or who needs to watch their sodium intake, Benson says.

Wraps, on the other hand, are Subway’s highest calorie and carbohydrate option despite getting a health halo. 

“If someone wants a wrap, that’s okay, but don’t choose the wrap just because diet culture says that they’re healthier in your sandwiches,” Benson says.

How to build a healthy Subway sandwich?

A nutritious, balanced meal has all three of the major macronutrients – carbohydrates, protein and fats. You’ve got the carbohydrates covered with the bread and likely have protein in the form of meat. You can get healthy fats in your sandwich by adding cheese, mayo, tuna or olives.

Try to load up that sandwich with as many vegetables as you can, Benson says.

“The more veggies, the more filling (it is), crunchy-texture wise,” she says. “It can add satisfaction as well too, hitting all of those areas which is really easy to do at a place like Subway.”

Discover more health tips for your daily diet: 

• Healthiest vegetable: Check out these great nutrient-dense options
• Healthiest bread: One is best, but your options for a healthy diet are plentiful
• Healthiest deli meat:Guide for your next sandwich, plus during pregnancy
• Healthiest soda:The answer is tricky – here’s what to know
• Healthiest lunch:Use this guide for a foolproof healthy meal

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