My behavior with lip balm is pretty much the same as my behavior with French fries: I just can’t get enough. There’s a lip balm (actually, three) in my purse at all times (sadly the same does not go for French fries), about four on my desk right now, and at least five tucked away in my apartment. Because nothing’s more annoying than the feeling of having chapped lips.

But although keeping your lips hydrated is important, dermatologists aren’t so keen on repetitive re-applying. As in, there can actually be too much of a good thing with lip balm. In fact, there are only a few times during the day when you should apply lip balm: When you wake up, after eating or drinking, and right before you go to bed.

… That’s it, according to Whitney Bowe, MD, a New York City-based board-certified dermatologist and author of Dirty Looks. “If you lick your lips while eating or drinking, you’re going to experience even more chapped irritation—it’s a vicious cycle because your saliva evaporates and causes you to keep licking to avoid the drying sensation,” she tells me. “Saliva also breaks down the delicate tissues and compromises the barrier.” She says to think about what it’s like when you put a saltine cracker in your mouth—without even chewing it, it’ll become soft. “That’s the saliva in your mouth slowly digesting the cracker into its building blocks…you don’t want saliva to eat away at your lips,” she says. Yikes.

And when you sleep, chances are you breathe out of your mouth. “I also apply right in the morning and right before bed,” says Dr. Bowe. “If you sleep with your mouth open, you’re going to dry your lips out even more, so I recommend that my patients apply a bit of lip balm right before bed.” So that’s roughly five times a day if you’re eating three meals.

Swiping on lip balm way, way more frequently than that? It can actually have the opposite effect of the smooth, moisturized lips you’re hoping for. “You might find yourself licking your lips over and over, which will unfortunately cause them to dry out even more (as a result of your saliva),” she explains. “Also, if you constantly apply occlusive products to your lips, this can interfere with the skin’s natural ability to adjust to changes in environment.” If you feel like you’re “addicted” to your lip balm, she notes that it’s usually because of irritating ingredients like menthol, cinnamon, and camphor—and if you feel like you need to reapply every hour, that’s not a good sign.

Her advice? Stick with her recommended times, and look for truly hydrating ingredients, like shea butter, in your lip balm. She likes the eos Active Lip Balm with SPF 30 ($3) because it’s super hydrating and has sun protection—perfect for that pout.