Antioxidants in Sunscreen: What and Why?

When you pick up your sunscreen, you’re holding years of trials, tests, and formulations in your hands. It’s a thoughtfully-developed product designed to defend your skin against sun exposure and its long-term effects—like early signs of aging and cellular damage.

At its core are UV filters, which absorb, reflect, or scatter UV radiation—whether physical (mineral) or chemical (organic). But not all sunscreens are the same. Some go further, featuring ingredients that enhance their protective benefits, such as moisturizers, stabilizers, and most importantly, antioxidants.

These powerful components aren’t always included, but when they are, they can make all the difference. So what’s the secret to more complete protection? Today, we reveal the key ingredient your skin will thank you for.

What are antioxidants?

If you think of your skin as your body’s protective barrier, it’s easy to understand how it’s constantly battling invisible aggressors: UV rays, pollution, stress…

These elements, known collectively as the exposome, trigger a process called oxidative stress, which speeds up visible skin aging and contributes to the appearance of fine lines, dark spots, and sagging.

That’s where antioxidants step in. These tiny heroes work to neutralize free radicals—unstable molecules generated by oxidative stress—before they can harm your skin. Think of them as a mini army defending against the breakdown of collagen and elastin (essential building blocks for healthy-looking skin).

But antioxidants don’t stop at prevention—they also help repair affected cells and strengthen the skin barrier, making it more resilient to daily stressors.

Now more than ever, you can find sunscreens with antioxidants. Paired with UV filters, they can enhance sun protection and support your skin’s natural defenses.

What do antioxidants do in sunscreen?

Your sunscreen acts as the first line of defense against UV rays, helping to shield skin from the harmful effects of the sun. Still, even with SPF protection, sun exposure can generate free radicals, which can disrupt the skin’s structure.

Here’s where antioxidants make a difference. When included in sunscreen formulas, they help neutralize free radicals, minimize oxidative damage, and support stronger, healthier-looking skin. Together, they offer more complete protection—especially against photoaging.

From sun to skin

Here’s what happens when you wear a sunscreen with antioxidants:

1. Sun exposure triggers free radical production→ UV rays activate processes in the skin that generate free radicals. These molecules can damage DNA, proteins, and lipids. The result? Visible signs of skin aging.
2. Sunscreen defends first→ UV filters absorb or deflect rays to help prevent short-term damage like sunburn and minimize the risk for more serious concerns such as skin cancer. But these filters can’t completely stop free radical formation.
3. Antioxidants step in→ They help neutralize free radicals before they can wreak havoc, supporting the skin and helping to prevent visible signs of aging.
4. Protection beyond UV→ Since free radicals can also be triggered by pollution and other daily factors, sunscreens with antioxidants help combat a wider range of skin stressors.

Top antioxidants in sun protection

Not all antioxidants are created equal. Some excel at neutralizing free radicals, others soothe or support repair, and a few offer multiple benefits in a single ingredient.

Let’s take a closer look at some of the most effective antioxidants used in sun protection:

Vitamin E

This fat-soluble antioxidant is found naturally in the skin. It helps protect skin from oxidative damage and supports elasticity and resilience.

In sunscreen, it helps reinforce the skin barrier, prevent moisture loss, and promote recovery from environmental stress.

Find it inside Eryfotona Actinica, Eryfotona Ageless, and Fusion Water MAGIC.

Mediterranean Algae extract

From the coasts of Valencia straight to our Barcelona lab, this specific type of algae has evolved for over 625 million years to survive in extreme environments. And its antioxidant power now supports your skin.

This extract helps support natural defenses, protect from oxidative stress, and boost hydration and elasticity—leaving skin more radiant and resilient.

Here at ISDIN, we obtain it through sustainable bio-agriculture techniques that help preserve marine ecosystems—part of our commitment as a Certified B Corp.

Discover it in Fusion Water MAGIC.

Physalis pubescens

Derived from husk tomatoes, this biotech powerhouse has developed its own ways to survive in tropical regions. Its natural processes help to minimize the effects of heat—and now it can help your skin do the same.

In sunscreen, it works to counteract free radical damage caused by high temperatures—helping to support skin, even in more extreme climates.

Discover it in Fusion Water MAGIC.

Above and beyond

Your skin is unique, and your sun care products should be, too. Antioxidants offer noteworthy benefits, from supporting and hydrating to fighting free radicals. Including them in your daily sunscreen is another way to help protect your skin.

Choose a formula that works for you and complement it with other targeted allies, like an antioxidant serum or moisturizer. And above all, love your skin, care for it, and give it your best—every single day.