As a board-certified dermatologist, I know that taking care of my skin goes beyond just the products I slather on. Many of the lifestyle choices we make every day can have a significant effect on how our skin looks and feels. Here are things you wouldn’t see me do because they’re just downright bad news for good skin!

1. Skip exercise. Getting a good sweat in regularly is directly connected to your skin’s radiance. Exercise boosts circulation and tones and strengthens your muscles so that the skin that on top will glow and even look better! Exercise also relieves stress, and there are tons of stress-related conditions like acne, eczema, psoriasis and hair loss that you can help improve by simply exercising. I love to spin, run, lift weights, kickbox and jump rope. Find activities you enjoy, and do them regularly—your skin will look better for it.

2. Sleep on my face. It’s not just an old wives’ tale: Sleeping on your face really does age your skin faster, as the pressure for hours overnight can cause wrinkles and more volume loss on the side of the face that you’re sleeping on. This all adds up over the days, weeks and years for more wrinkles and sagging. Sleeping on your back is the ideal position, though difficult for many—and I admit that even sometimes I slip—but I encourage you to make it as much of a habit as possible since it’s a free and easy way to help slow the hands of time on your face that really makes a difference.

3. Skip washing off makeup. During the day, makeup sitting on your skin can collect dirt and bacteria as you walk around and live in your environment, and it’s even worse if you live in an urban area. At night, washing your face with a gentle cleanser decreases the bacterial colony that has developed on your face. (Gross, but true.) If you don’t take the time to wash your face at night, bacteria-feeding conditions like acne can be aggravated and skin can grow dull and lackluster from the lack of exfoliation. Sleeping with mascara on can dry out your eyelashes and subsequently thin them out, too. You don’t want that, because everyone looks younger with longer, fuller lashes.

4. Go in a tanning booth. No way, not ever! First, there’s cancer—research shows that baking in a bed before the age of 30 increases the risk of melanoma (the deadliest form of skin cancer) by 75 percent for the rest of your life, and all booth bathers have an increased risk for melanomas of the eyes, as well as for squamous cell and basal cell carcinomas. And then there’s beauty—tanning booth rays will prematurely wrinkle, sag and spot your skin before its time, due to the concentrated rays that the World Health Organization (WHO) has assigned the most highly carcinogenic label.

5. Walk out without sunscreen on. This is skincare 101 for a reason. Applying a sunscreen of SPF 30 or above daily will help prevent every symptom of aging, as 90 percent of visible aging comes from the sun’s UV rays. The shield will also help prevent cancer and other common dermal conditions like psoriasis and rosacea from flaring up. My face, ears, neck and hands are always sunblocked when I walk out of the house. In hot weather when my arms and legs are bare, they also get the sunblock treatment before I head out for the day. Have you ever heard the saying, “One stitch in time saves nine”? This is especially true for sunscreen use, since prevention is always better than having to treat those sun spots and wrinkles down the line!