Like when you found out what sex was or that Lance Bass is gay, discovering that you've been wearing the wrong bra size is a life-altering moment.

Unfortunately, a lot of women are still living in the dark, says Lori Kaplan, director of Bra*Tenders lingerie store in New York City. And ignorance is definitely not bliss. "When you're wearing the right-sized bra, you can look 10 pounds thinner and 10 years younger in a minute," says Kaplan. That's because, when your girls are lifted, your waist is more distinguishable and your torso looks longer, she says.

RELATED: 31 Ways to Have More Fun With Your Boobs Every Day

Though Kaplan recommends getting professionally fitted for a bra once a year, you can assess how your goods look in your current bra with the pointers below from Kaplan. Are your boobs hanging tight—or are they ready for an upgraded boulder holder?

this image is not available
Media Platforms Design Team

RELATED: 7 Guys Reveal the Sexiest Lingerie Ever

this image is not available
Media Platforms Design Team

RELATED: Smoking-Hot Lingerie That Won’t Make You Feel Skanky

this image is not available
Media Platforms Design Team
Headshot of Ashley Oerman
Ashley Oerman
Contributing Writer

Ashley Oerman is a contributing writer at Cosmopolitan, covering fitness, health, food, cocktails, and home. You can follow her on Instagram @AshleyOerman. She is pro-carbs.