You need dietary Vitamin C for the health of your joints, bones and immune system, but applying vitamin C may also improve the health of your skin and slow skin aging. Here are five reasons topical vitamin C is beneficial for your skin.

1. Vitamin C protects against antioxidant stress that accelerates skin aging

Vitamin C has natural antioxidant activity. Antioxidants prevent the formation of free radicals that damage skin cells and contribute to skin aging. Why is this important? Every time you step outside, you expose your skin to factors that create oxidative stress. These factors include sunlight and pollution from the air. If you smoke, cigarette smoke also increases the formation of free radicals that cause your skin to age faster.

Vitamin C may even offer sun protection.  Studies in mice show that those treated with topical vitamin C developed less redness when their skin was exposed to sunlight. Another study in humans showed that applying a 10% solution of vitamin C to the skin before exposure to sunlight reduced skin redness.

You should still wear sunscreen, but using a vitamin C serum or cream could boost your defense against oxidative stress related to sun exposure.

2. Supports healthy collagen production

Collagen is a protein that supports the skin and makes it more resistant to wrinkling. Vitamin C plays an essential role in building healthy collagen. When scientists add vitamin C, also known as ascorbic acid, to cultures of skin cells, it boosts collagen production. In turn, healthy collagen production makes skin more wrinkle-resistant and less prone to sagging. In turn your skin often feels tighter.

In one study, (1) subjects applied topical vitamin C that contained zinc and tyrosine to their skin for 90 days. By the end of 90 days, their skin texture was smoother and fine lines and wrinkles had improved. Plus, their skin looked and felt smoother and more youthful. Some products combine vitamin C with weak acids such as glycolic acid that also have anti-aging benefits.

3. Vitamin C lightens pigmented areas

Many people develop areas of increased skin pigmentation, a problem where too much melatonin deposits in the skin. These dark spots may be discrete, in the form of sunspots, or more diffuse, a condition called melasma. In one study of people with melasma and sunspots, topical vitamin C lightened the areas in 19 of 34 subjects without affecting the color of the surrounding skin. How does vitamin C lighten dark areas? It blocks the activity of an enzyme called tyrosinase that synthesizes the skin pigment melanin.

4. May be beneficial for stretch marks

Stretch marks are linear “scars” that form on the skin when the skin is stretched too far. Also known as striae or striae distensae, are a form of scarring that often show up after pregnancy or when an individual gains weight in a short period, placing added stress on their skin. A study found that vitamin C combined with glycolic acid improved the appearance of stretch marks. Stretch marks respond if you treat them soon after they appear.

5. Vitamin C improves skin hydration

As skin ages, it dries out and needs more moisture. When you moisturize and hydrate your skin, it softens the appearance of fine lines and wrinkles. Magnesium ascorbyl phosphate is a form of vitamin C that improves skin hydration. Look for a moisturizer that contains vitamin C and you’ll get multiple skin anti-aging benefits.

Vitamin C breaks down easily in the presence of heat or light. The best vitamin C products come in dark containers that limit light exposure. Some forms of topical vitamin C are more stable than others. For example, ascorbyl palmitate combines ascorbic acid with palmitate for added resistance to breakdown. Another form of vitamin C called magnesium ascorbyl phosphate is also stable and may be easier for your skin to absorb.

Topical vitamin C has multiple benefits for aging skin. However, it’s important to choose a form of vitamin C, like magnesium ascorbyl phosphate, that’s stable and comes in a dark, air-tight container. You can find a variety of skincare products that contain vitamin C. Do your research and choose carefully. There are some great trusted skincare brands out there that you may want to try. If you use vitamin C in isolation, use a moisturizer afterward, as you may experience dryness, redness and slight irritation when you first start using it. If you experience a more severe skin reaction after using topical vitamin C, see your dermatologist.

(1) Dr. Leslie Baumann