Maybe you take all the right steps to care for your skin. But simple, seemingly innocuous habits like a daily cup of coffee may be undermining your best efforts, according to New York City dermatologist Dr. Deborah Wattenberg. Here’s what to avoid to keep your skin looking young and healthy.

1. Seriously, stop smoking.

“Smoking is probably the worst thing you can possibly do for your body, including your skin,” Wattenberg explains — yet 20 percent of Americans are still lighting up.

Here’s just one reason to consider kicking the habit: Nicotine and other chemicals found in cigarettes destroy the skin’s elastin and collagen, leading to wrinkles and fine lines. Smoking also takes a toll on the skin’s blood vessels, restricting oxygen flow and subsequently causing your skin to appear dull and sallow. Habitual smoking can also lead to those pucker lines around the mouth, Wattenberg says.

2. Wine, candy and coffee are aging your skin.

Turns out, all of your favorite vices — alcohol, junk food and caffeine — are wrecking your skin, too. “Alcohol and caffeine … act like a diuretic and prevent you from holding on to water, so your skin looks sort of prune-like. It can get dry and get washed out,” Wattenberg says. “Junk food contains a lot of preservatives and that will do the same thing.”

So if you’re drinking a lot of caffeine or alcohol, remember to stay hydrated. We need about six to eight glasses of water per day, anyway, but if you’re drinking a lot of lattes to get through the day, you’ll need to drink even more water to keep your skin looking pretty.

3. Your lack of sleep is written all over your face.

Actually, if you’re drinking caffeine to stay alert throughout the day, we need to talk about that, too. You may think you’re getting away with six hours of sleep a night, but your skin tells the real story.

“When you don’t sleep, stress causes the release of the hormone cortisol, (which) makes your skin oily (and) causes acne, which makes your skin look less attractive,” Wattenbergy says.

4. Be nicer to acne-prone skin.

This is counterintuitive, but Wattenberg says when your skin breaks out, make sure you don’t scrub your face too aggressively. “The worst thing you can do when you have acne is to try to scrub away your acne,” Wattenberg says. “People try to do that all the time, and come in with irritated faces as a result of scrubbing or overwashing.”

Acne, she explains, isn’t caused by dirt or uncleanliness — it’s hormones that are more likely making you break out. So instead of rubbing your face raw, wash gently, using products that are going to target the acne like salycilic acid. “And you don’t want to pick and squeeze — it causes scarring, pigmentation and makes it worse because you can drive the bacteria deeper into the skin and create infections,” Wattenberg says. Yikes.

5. You’re not wearing enough sunscreen.

Yes, we know it’s winter. But you still need to apply sunscreen — several times a day, Wattenberg insists. “Once a day is probably one of the worst things you can do for your skin, because the sun is still really strong, and people spend a lot of time outdoors,” she explains.

Especially in parts of the country where the weather is turning snowier and icier, remember to reapply your sunscreen — the sun reflects off the snow and ice, and you can get burned easily. “Sunscreen is the key to youthful skin,” she says.

OK, now we know what not to do. But let’s focus on the positive here. Check these 6 coffee alternatives to start your morning off right.