Eat this, not that at the drive thru

HOUSTON (KTRK) -- It happens. You're hungry and need something quick, so you hit the drive thru. It's okay, and you don't have to kill your diet in the process.

Fast food typically means junk food, but if you choose correctly you can eat healthier at several stops. The better choices are obvious, but how bad are the bad choices?

Personal trainer Kathy Laucius at the Next Level Fitness Gym wasn't always so fit. The 40-something mother of two says she struggled with her weight and weighed over 200 lbs. at one point.

"As my old trainer used to say, you got to get down to get it round," Laucius said. "I have walked the walk, I understand what the journey takes, I know how hard it is to put one foot in front of the other, I know how hard it is to eat clean."

When her clients are on the run, she says the first choice should be the grocery store's salad bar.

Calorie counts for fast food favorites

But if you find yourself at a McDonald's, don't order the Big Mac.

"Big Mac alone has 530 calories and 27 grams of fat," Laucius said.

If you add a large fry, it's an additional 510 calories and 24 grams of fat, and that doesn't include the soda.

Instead, Laucius says choose the Premium Southwest Grilled Chicken Salad. It has 290 calories and 8 grams of fat. Adding the low fat balsamic dressing adds an additional 35 calories and 2 grams of fat.

If you find yourself at Starbucks, do yourself a favor and skip the BLT Chicken Salad Sandwich. It's 470 calories with 25 grams of fat, almost as much as the Big Mac.

"He's so cute and small and looks like a good size portion," Laucius said.

Some people might even pair the sandwich with the lemon pound cake, which comes in at 470 calories with 20 grams of fat.

A healthy alternative would be the Zesty Chicken and Black Bean Salad Bowl at 360 calories and 15 grams of fat.

At Chick fil A, Laucius says it's easy to be deceived. A regular Chicken Sandwich will set you back 440 calories and 18 grams of fat. A much better option is the Chargrilled Chicken Sandwich.

"This guy has 320 calories, 5 grams of fat, and an added 3 grams of fiber," Laucius said.

Making the right choices is how Lucius was able to shed 40 pounds.

"I know what it's like. I work during the day, but I have my children, I drive that bus," Laucius said.

But choosing the healthiest option will get you results.

Laucius says her clients say they struggle with snacking. She suggests bringing your own. It will not only save you money, but calories too.