*Welcome to Ask A Dermatologist. In this series, we’re putting the big skin questions in front of some of our favorite dermatologists. First up: board-certified dermatologist Dr. David Kim on everything you need to know about dry skin. *

Let’s start with the basics: what causes dry skin? Is it genetics? Environmental?

It’s mostly due to genetics, but we can extrinsically cause dryness by excessively cleansing our face. It’s very similar to how many people are experiencing dry hands from using hand sanitizer and washing their hands multiple times a day now. Patients with eczema also have much more sensitive skin and they’re at an increased risk of having dry skin.

Is age a factor?

Age plays a role too. As we age, we lose our ability to hold onto moisture so moisturization, not just to the face but also to the hands, arms, and legs, becomes very important.

So what can we do? What helps dry skin and what makes it worse?

Thick oil-based moisturizers will always help, especially ones with ceramides. Ceramides are lipid molecules that are naturally found in the skin and they hold the skin cells together to keep the skin barrier intact and lock in moisture. One quick way to differentiate between a cream and a lotion is the packaging. A cream usually comes in a tub, whereas a lotion usually comes in a dispenser. Emollients, like Vaseline or Aquaphor, can be used on top of moisturizer to lock in all the moisture.

When you have dry skin, your skin barrier is significantly compromised so avoiding any products (including shampoo, body wash, hand soap, and skincare) with fragrance or artificial coloring is important. Water alone is one thing, but when someone excessively cleanses with soap, facial cleanser or body wash, it can strip and dry out the skin.

Let’s talk more about the skin barrier — what is it exactly and how does it function?

The skin barrier is composed of the outer layers of the skin. A strong skin barrier is one that is intact and hydrated without any micro tears. There are various lipids and protein molecules that are essential to the integrity of the skin, but when you have eczema or wash your skin excessively, you can strip your skin of these lipids and cause micro tears. This can compromise the skin barrier and put you at a risk for irritation and infection.

What are some key skincare ingredients to look for if you have dry skin?

Products with thick emollients, like petroleum jelly, are great for dry skin. Sunflower seed oil and macadamia seed oil are two natural emollients that also have anti-inflammatory properties.

Hyaluronic acid (HA) can have a plumping and hydrating effect on the skin, but it’s best for skin that is not compromised. If you have truly dry skin or compromised skin (eczema, for example), you can’t rely on HA alone for moisturization. You want to look for calming and moisturizing ingredients like oat, ceramides, and petroleum jelly.

What products are essential in a dry skincare routine?

For patients with dry skin, I recommend using gentle cleansers like Cetaphil or Vanicream face wash. You can add a vitamin C serum to give skin a boost of antioxidants. I like Paula's Choice C15 Super Booster, Drunk Elephant C-Firma Day Serum, and SkinCeuticals CE Ferulic. Ferulic acid stabilizes vitamin C, so it's a good ingredient to look for in combination with vitamin C. Keep in mind that vitamin C is unstable when exposed to oxygen and light so you want to look for a product that is in an airless pump or in a dark bottle. It's ideal if you finish the product in 4-6 months.

And of course, a rich moisturizer or emollient is key. For patients with eczema and sensitive skin, I recommend products without fragrance. However, for patients with dry skin without any underlying dermatologic conditions, fragrances are ok! The goal is to keep your skin barrier intact to minimize your risk for irritation or infection.