At the start of the new year, you probably promised yourself that you were going to eat healthy and exercise more. Your Pinterest board was filled with Buddha bowl recipes, and that pair of gym shoes was getting more action than it used to. But as January marches toward its end, you find yourself taking fewer Mason jar salads to work, and you can’t even remember the last time you went to the gym.

It’s those times that you have to lean on healthy habits you’ve developed when your willpower was stronger. In a sea of seemingly unhealthy fast-food options, there are still ways to approach a menu and fill up on nutritious items. To help with that, we asked two dietitians to give us some tips and tricks for choosing healthy options and then made them prove the tips would work by taking them to popular fast food and fast casual restaurants.

We accompanied Bethany Doerfler, a registered dietitian at the Digestive Health Center at Northwestern Medicine, and Lori Welstead, a registered dietitian and nutritionist at the University of Chicago, to some of Chicago’s favorite lunch spots to show us how to hack the menu for the healthiest options and give us tips on how to stay on track.

Their suggestions are geared toward people who want to maintain their weight or lose weight. For women, this means a 1,200- to 1,600-calorie daily diet, and for men, 1,600- to 2,000-calories a day. To accomplish those numbers, Doerfler recommends sticking to 400 calories for breakfast and lunch and 500 calories for dinner, which leaves some room for “two thoughtful snacks.”

Don’t despair. There’s still hope for your New Year’s resolutions.

STUDY AHEAD

It’s easy to go into a restaurant, look at the menu and pick something on the spot, but Doerfler recommends studying ahead. See if you can check out the menu online, or pick one up when you’re there — some restaurants even have a calorie calculator to help you make better choices.

“Go in with a game plan,” Doerfler said. “Don’t show up and ask what looks good because everything looks good. You’re less likely to make an impulsive decision.”

Examine the calories, fat, sodium and sugars if there is a menu available with that information, Welstead said.

Once you get into the habit of checking nutrition information, it will be easier to modify your meal to make it lower in calories and healthier, Doerfler said.

FIND THE IN-BETWEEN

It’s all about finding a combination of foods that are not only healthy but will also satisfy whatever you’re craving, whether it’s something spicy, savory or sweet. You don’t want to fall into the trap of eating something nutritious but unsatisfying and then later grabbing a candy bar, Welstead said.

At Panda Express, Welstead chose the kung pao chicken bowl with steamed vegetables, garnished with peanuts and chile peppers, to bring the total calorie count to just under 400. She chose the kung pao chicken because it’s a savory and spicy option that is packed with protein.

“When it comes to making these healthy choices, and I think with regard to making a healthy lifestyle, it’s all about balance,” Welstead said. “If you know you want to eat something that is higher in calories, higher in fat, higher in sugar, enjoy it, have that meal, and the next time you have something to eat, make better decisions.”

GO FOR PROTEIN

Choosing options high in protein helps keep you satiated, Welstead said. And while skipping the rice, bread or noodles is preferred — since carbohydrates cause your blood sugar to spike and then drop down — getting a half or partial portion is better than getting the entire serving. Also, skip the lunchmeat.

“Unfortunately when you get things like lunchmeat, there’s not going to be as much bang for your buck when it comes to protein, and it’s going to have more salt,” Welstead said.

When you eat something with as many carbohydrates as a sandwich, your blood sugar will go up and then inevitably crash only a few hours later. If you’re going to have a sandwich at a place like Potbelly’s, choose the skinny bread or the flat instead of the normal bread, Welstead said.

At Potbelly Sandwich Shop, Welstead opted for half a tuna salad, to cut down on red meat and avoid lunchmeat, on whole grain bread, which has fiber to help you stay full and satisfied.

“A pretzel bun or baguette might sound good, but they have no whole grains and so many more carbohydrates because of the dense nature of it,” Welstead said.

Because Corner Bakery Cafe offers the option of getting half a sandwich and a salad, Welstead ordered the Asian wonton salad with the wontons on the side.

GO EASY ON THE DRESSING AND CRUNCHY BITS

Crunchy toppings, like croutons and wontons, can add empty calories to a meal, so opt to have them on the side and have only one or two pieces to appease that hankering, Welstead said.

Dressings can add a lot of calories and sugar to your meal, so the best option is to get it on the side and use only a little bit, Welstead said. Avoid nonfat dressings because they typically have more sugar than normal ones, and opt for avocado, which has healthy fats to help you stay full longer.

Welstead chose the Powerhouse salad at Potbelly’s, made with grilled chicken breast, avocado, hummus, hard-boiled egg, cucumber and grape tomatoes on a bed of spinach. She ordered the Potbelly’s vinaigrette on the side.

“When you get salads with avocado, you won’t have to use as much dressing because it gives that creamy consistency when you start to toss your salad,” Welstead said.

If you’re craving more punch, hot sauces, rather than creamy or garlic oils, are a way to amp up flavor and avoid adding calories, Doerfler said. Another way is to choose chimichurri or salsas, which helps bump up your vegetable intake while making your meal more interesting.

START LOW AND WORK THE SIDES

Building a bowl with salad as your base already gives you a good start toward clocking in fewer than 500 calories for a meal, Doerfler said. This way, you can layer in other healthy things without worrying about overdoing it.

When entrees are too high in calories, check out the sides or a la carte options to build a satisfying meal. At Portillo’s, Doerfler ordered an a la carte meatball, minestrone soup and a grilled chicken sandwich without mayo or cheese.

Sides like soups and salads can help keep calories down while giving you a variety of options that are filling. Studies have shown that starting a meal with a broth-based soup can help people cut back on calories by 30 percent, Doerfler said.

At Noodles & Company, Doerfler ordered a tomato basil bisque with her small penne rosa.

“Save some of the good carbs that you’re craving for times like this when you can do a small or half order. That way you’re getting portion control right out of the gates,” Doerfler said.

DRINK WATER, EAT COLORFULLY

Instead of reaching for a fountain drink or sweet iced teas, drink water. Other drinks can add unwanted sugar and don’t help keep you full. Instead of picking a sweet drink, save those calories for a healthy afternoon snack, Doerfler advised.

“Try to skip all the sodas and milkshakes that can add easily 1,000 calories when you otherwise weren’t planning on it,” Doerfler said.

A regular soda can be the caloric equivalent of four or five pieces of bread, Welstead said, so cutting those out saves you hours of exercising to burn off those extra sugars.

A quick rule that Doerfler and Welstead give their clients is to eat something green, something red or purple, and something yellow or orange every day to ensure they get the antioxidants they need.

“Get all the colors of the rainbow,” Welstead said.

SHARE WITH FRIENDS

People often fall into the trap of finishing their entire plate even if they’re already full. Instead, try to take home leftovers or share with friends, Doerfler said. And if that item wasn’t what you thought it would be or you just aren’t enjoying the taste anymore, don’t be afraid to get rid of it.

“When you feel like you are no longer enjoying the taste and you’re eating just to finish, it’s a great time to try to stop and pause,” Doerfler said. “Take the leftovers home with you, or give them to a friend, or throw them away. Save your heart and health in the long run.”

CASE STUDIES

Here are the restaurants and businesses that Welstead and Doerfler visited, what they ordered and their explanations for their picks.

Panda Express

>> Order: Kung pao chicken with steamed vegetables

>> Reasoning: The chicken is for protein, and the vegetables are for nutrition and as a substitute for rice or noodles.

7-Eleven

>> Order: Yogurt and hard-cooked eggs.

>> Reasoning: It’s hard to choose something that is healthy at 7-Eleven, so choose something with protein. Plain nuts are also a good choice. Avoid yogurt-covered nuts because they are just covered in sugar and aren’t made with real yogurt.

Whole Foods

>> Order: From the salad bar, a kale salad base topped with shrimp, chicken or hard-cooked eggs. Or a packaged salad.

>> Reasoning: The kale provides a good amount of fiber, and the shrimp provides protein. Add nuts, chia seeds or sunflower seeds for crunch, rather than croutons or wontons.