Do you ever feel like your deodorant just isn't working?

(A.K.A. You realize that the B.O. smell is coming from you more often than you'd like to admit?)

Well, we enlisted gastroenterologist Dr. Roshini Raj to tell us what's going on!

For starters, contrary to what we might think, sweat doesn’t smell, Dr. Raj says.

(Wait, what?!)

“When you think about the liquid that’s coming out, it’s actually odorless,” the doc says.

What about that stink, though? That comes from your sweat interacting with bacteria on your skin. This creates different chemicals, which results in odor, explains Raj.

RELATED: How to Control Annoying Breast Sweat

So what can you do about it? Luckily, Dr. Raj has a few suggestions.

THINK ABOUT WHAT YOU’RE EATING

Spicy food, onions, garlic, and alcohol can all contribute to body odor, the doc explains. (Rach admits that she’s in trouble!)

It makes sense after all — garlic breath, anyone?

The answer here? Moderation is key!

SKIP THE SYNTHETIC FABRICS

What you’re wearing also makes a big difference.

“You want to make sure you’re sticking to natural fibers,” says Dr. Raj. “Cotton is great. [It's] really going to wick away the moisture and absorb it. Because moisture is actually something that really helps bacteria grow and thrive.”

On the other hand, synthetic fibers, like rayon, can trap odors.

RELATED: Can You Eliminate Sweating and Underarm Hair—Permanently?

CHOOSE DEODORANT WISELY

When you’re thinking about deodorant, you want to choose one that has at least 12 percent aluminum chloride, the doc suggests. She says to look for antiperspirant and deodorant all in one product. (One will help keep wetness at bay while the other will keep you smelling fresh!)