How Do Antioxidants Work?

Last Updated on December 3, 2025 by Giorgia Guazzarotti

I can’t get enough of antioxidants. If a serum or moisturizer isn’t loaded with them, chances are I won’t even give it a second look. Antioxidants are your skin’s police force. They patrol your body looking for free radicals felons ready to form wrinkles, give you dark spots and inflame your skin. Once they get hold of one, they destroy it before it can wreak its damage. Here’s how antioxidants work and why you should load your skincare routine with them if you want younger-looking skin:

What Are Free Radicals?

First things first: to understand antioxidants, you must first get to know free radicals. Free radicals are your skin’s #1 enemy. They’re highly unstable molecules caused by something called “oxidization process”. Here’s the simple version: a healthy molecule turns into a free radical when it loses one its electrons. Without it, it goes crazy. It must get it back and become whole again.

When it spots a healthy molecule, the free radical attacks it and robs it of its electron. The robbed molecule is now a free radicals. Now, it’s its turn to become a thief. It’s the beginning of chain reaction that destroys anything in its path, including vital proteins such as collagen and elastin and even cellular DNA.

Free radicals speed up the aging process. In the best case scenario, this only gives you wrinkles and dark spots. In the worst case scenario, it can lead to deadly diseases, such as cancer and heart diseases. But, what starts this nasty chain and turns a healthy molecule into a free radical in the first place? All the usual culprits:

• Alcohol
• Body processes like metabolism and breathing
• Diet rich in sugar and poor in vegs
• Pollution
• Smoking
• UV rays

You can’t stop breathing or eating, but you can nourish your body with healthy foods, drink alcohol in moderation, wear sunscreen every day and quit smoking. The healthier a lifestyle you lead, the fewer free radicals your body has to deal with. But, that’s not always fun. So, let’s see how to destroy those nasty free radicals.

Related: I Went On The Low Glycemic Diet And It Transformed My Skin

Struggling to put together a skincare routine that minimises wrinkles, prevents premature aging, and gives your complexion a youthful glow? Download your FREE “Best Anti-Aging Skincare Routine” to get started (it features product recommendations + right application order):

What Are Antioxidants And How Do They Keep Skin Young?

Enter antioxidants. They’re your body’s natural defence mechanism against free radicals. The most famous members of the antioxidant family are:

• Beta-carotene: The orange pigment in carrots and sweet potatoes. Your body converts it into vitamin A, but it also works as an antioxidant on its own. It’s especially good at protecting your skin from sun damage by neutralizing the reactive oxygen that UV rays create.
• Coenzyme Q10: Lives in your cell membranes and mitochondria, doing double duty – it helps cells produce energy AND fights free radicals. The problem? Your body makes less of it as you age (levels can drop by half in older skin). That’s bad news because less CoQ10 means more oxidative damage. The good news is topical CoQ10 can penetrate your skin and help protect your collagen and elastin from breaking down.
• Flavonoids: This is a huge family of over 6,000 plant compounds. In skincare, the big players are quercetin, rutin, and catechins. They work in multiple ways – scavenging free radicals, preventing metal ions from triggering oxidation, and calming inflammation. Some flavonoids are better at UV protection, others excel at reducing redness or strengthening capillaries.
• Green tea: The real star here is EGCG, a polyphenol that does way more than just neutralize free radicals. It fights inflammation, helps control oil production, and can even wake up dying skin cells.
• Resveratol: The compound in red wine everyone got excited about. In skin, it activates sirtuins – proteins that help cells stay healthy and live longer. It’s great at scavenging free radicals and also blocks the enzymes that destroy collagen.
• Superoxide dismutase: This is actually an enzyme your body makes naturally. It’s one of your first defenders, specifically converting superoxide radicals (really nasty ones) into hydrogen peroxide and oxygen, which other antioxidants then neutralize. Your SOD levels drop with age and sun exposure. Getting it into skin topically is tricky because it’s a big molecule, but some products use special delivery systems to help it penetrate.
• Vitamin C: The superstar of skincare antioxidants. It neutralizes free radicals, but that’s just the beginning. Your skin can’t make collagen without it – literally impossible. It also stops melanin production, which brightens your skin and evens tone. It teams up beautifully with vitamin E, actually bringing oxidized vitamin E back to life so it can keep fighting free radicals. The downside? It breaks down fast when exposed to light and air, so packaging matters.
• Vitamin E: This fat-soluble antioxidant sits in your cell membranes, protecting the fatty parts of cells from oxidative damage. It’s particularly good at neutralizing free radicals created by UV exposure and works best when paired with vitamin C.

Their job is to destroy every free radical they see before they can wreak their damage on your skin. They do this in two ways, depending on the antioxidant’s MO:

• Chain-breakers: these antioxidant break the free radical chain after it’s started. Examples include vitamins C and E.
• Chain-neutralizers: these antioxidants neutralize the initiating free radicals, slowing down or even preventing the chain reaction. Examples include superoxide dismutase.

Related: Is Superoxide Dismutase The Most Powerful Antioxidant Of All?

How To Use Antioxidants To Help Prevent Free Radical Damage

Because EVERYTHING (well, almost!) causes those pesky free radicals, free radical damage is constant. Every single day your body has to deal with these felons and destroy them. But, it can’t do it alone. Your body is well-equipped to cope with free radicals caused by metabolic processes, but these days it has to also put up with antioxidants caused by pollution, our unhealthy Western diet, tanning habits… It’s too much for it to handle alone.

Your body needs your help. Quitting bad habits like smoking and heavy drinking is a great place to start. But, your body also needs you to constantly replenish it with a new stream of antioxidants. You can do it in two ways:

1. Eat a healthy diet full of antioxidants-rich fruits, vegs and berries
2. Use skincare products loaded with antioxidants

Skincare is my area of expertise, so I’m sharing with you my fave antioxidant serums and moisturizers below:

What Are The Best Skincare Products With Antioxidants?

• Paula’s Choice Resist Ultra-Light Super Antioxidant Concentrate Serum ($49.00): A lightweight serum with a high concentration and number of antioxidants. Available at and Paula’s Choice
• The Ordinary EUK 134 0.1% (£10.75): It contains one of the most powerful antioxidants of all, a form of Superoxide Dismutase. Available at Beauty Bay, Cult Beauty, The Ordinary, and Yes Style.
• Skinceuticals CE Ferulic ($169.00): The original Vitamin C serum, it costs an arm and a leg, but it works wonders and delivers what it promises. Available at Dermstore and Skinceuticals.
• Drunk Elephant C-Firma Day Serum ($79.00): A hydrating, slightly tacky Vitamin C serum loaded with antioxidants. Best for dry skin. Available at Cult Beauty, Sephora, SpaceNK and Ulta

Related: 5 Things No One Ever Told You About Antioxidants

FAQs

Do antioxidants really work for anti-aging?

Look, I get it. The skincare industry makes so many promises that it’s hard to know what actually works. But antioxidants? They’re the real deal. Free radicals are literally tearing apart your collagen and elastin every single day – from the sun, pollution, that glass of wine you had last night, even just breathing. Antioxidants jump in and neutralize these little bastards before they can do their damage. The research backs this up big time. People who use antioxidants consistently see fewer wrinkles, brighter skin, less sun damage. But here’s what skincare companies won’t tell you: you can’t just slap on a vitamin C serum once and expect miracles. This is a daily battle. Your skin needs a constant supply of antioxidants to keep up with the constant assault of free radicals. And even then, they ONLY PREVENT wrinkles, they don’t get rid of the ones you already have.

What’s the best antioxidant for skin?

Ugh, I hate this question because everyone wants one magic ingredient. But that’s not how skin works. Vitamin C is incredible for boosting collagen and brightening, but it sucks at protecting your cell membranes – that’s where vitamin E comes in. Green tea is a rockstar at calming inflammation, but it won’t do much for hyperpigmentation. Resveratrol activates those longevity proteins, CoQ10 keeps your mitochondria happy. See where I’m going with this? They all have different jobs. The smartest thing you can do is use products with multiple antioxidants. They actually work better together – vitamin C literally brings vitamin E back from the dead so it can keep fighting free radicals. How cool is that?

Can I get enough antioxidants just from eating healthy?

I wish. Eating tons of berries and veggies is amazing for your overall health, and your body definitely needs those antioxidants. But here’s the annoying part: when you eat antioxidants, your body has priorities. Your heart? Super important. Your brain? Yeah, that needs protecting. Your skin? It’s at the bottom of the list. Your skin only gets whatever antioxidants are left over after all your vital organs have taken their share. And honestly, that’s usually not much. That’s why you need to apply antioxidants directly to your skin. It’s the only way to guarantee your skin actually gets a decent amount.

Should I use antioxidants in the morning or at night?

Morning, for sure. Think about when free radical damage actually happens. During the day, right? You’re out in the sun, breathing in pollution, exposed to blue light from your computer. That’s when free radicals are going crazy. Using antioxidants in the morning is like giving your skin armor before it goes into battle. They work alongside your sunscreen to protect your skin from all that environmental crap. Now, can you use them at night too? Absolutely. They’ll help repair damage while you sleep. But if you’re only going to use them once a day, make it morning.

Can antioxidants replace sunscreen?

God, no. I cannot stress this enough. Antioxidants are amazing, but they don’t block UV rays. Sunscreen physically or chemically blocks those rays from penetrating your skin. Antioxidants deal with the free radicals that UV exposure creates. They’re teammates, not substitutes. Using antioxidants with sunscreen actually boosts your sun protection – some studies show vitamin C can increase your SPF’s effectiveness. But on their own? They’re not stopping UV damage. Wear your damn sunscreen.

Why do some vitamin C serums turn brown?

Because vitamin C is a diva. It’s one of the most unstable ingredients in skincare. The second it’s exposed to light or air, it starts breaking down. That brown or yellow color means it’s oxidized and basically useless. All those amazing benefits? Gone. This is why packaging matters so much with vitamin C products. You want dark or opaque bottles, airless pumps, anything that keeps light and air out. And even with good packaging, vitamin C has a shelf life. If you’ve had that serum for over a year, or if it’s changed color at all, throw it out. You’re just rubbing oxidized garbage on your face at that point.

Can you use too many antioxidants?

Nope, and this is what I love about them. Unlike acids that can burn your face off, or retinol that can irritate the hell out of your skin if you overdo it, antioxidants are pretty chill. You can layer multiple antioxidant products without your skin freaking out. In fact, using different types together is actually smarter because they complement each other. A serum with vitamin C, vitamin E, and ferulic acid? That’s a powerhouse combination. A moisturizer with CoQ10 and green tea on top of that? Go for it. Your skin will thank you. The only “too much” is if you’re spending a fortune on ten different antioxidant products when two or three good ones would do the job.

The Bottom Line

Antioxidants are your skin’s BFF. Eat them up. Slather them all over your face. Give your skin the daily dose it needs. You’ll age a lot more slowly and keep your complexion clear and younger-looking for longer.