If you're here, you already know that vitamin C is good for you. Maybe you take it orally (Glossier HQ is continually on an Emergen-C kick, just to be safe). Or perhaps you found a serum that really suits you. Either way, you're doing your skin and body some definite good.

But what kind of good? In the interest of some useful, back pocket happy hour conversation (but also, you know, understanding why you're actually slathering your skin in stuff), here is a laundry list of things vitamin C can do for you. Besides stave off scurvy. But yeah, it does that, too.

Defends against free radicals
Vitamin C is an antioxidant, which is good news. To get sciencey about it, vitamin C can donate electrons in order to neutralize free radicals created in skin after oxidative stress. Oxidative stress = sun damage. So while vitamin C can't protect skin like an SPF can, it can minimize the damage you can't see.

Boosts collagen production
Very exciting news: Vitamin C is one of the factors in stabilizing and creating collagen molecules, meaning that it's one of the most reliable anti-aging ingredients on the market. Some research also shows that vitamin C can also increase the quality of the collagen created in the body. So while topical (and drinkable) collagen aren't necessarily doing you any good, your Amazon-sourced vitamin C serum's been pulling double duty.

Reduces brown spots
Because vitamin C can aid in skin's ability to heal itself, it should be your go-to when looking to reduce red and brown spots. Add to that its anti-inflammatory properties (of interest if you're struggling with acne or rosacea), and even-toned skin is in your very near future. You already knew you were preventing damage with it; but now you're also fixing it post facto.

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A quick note before we proceed to the fun part (product recommendations!): Vitamin C sounds simple, but there are actually several different kinds of vitamin C to be aware of. Ascorbic Acid is the most common when it comes to skincare—it absorbs the quickest and has the highest potency when applied topically. Magnesium Ascorbyl Phosphate (MAP) is another water-soluble derivative of vitamin C that can be effective in lower concentrations. Then there's Ester-C, a trademarked form of vitamin C that's been amped up with Calcium Ascorbate. This one comes with a lot of claims, but not a whole lot of data backing up. When in doubt, look for Ascorbic Acid. That's really the one you want.

Regardless of which version you choose, any vitamin c product will destabilize when it comes into contact with the air. Remember what we said about oxidative stress? This is the downside of losing those electrons. Of course, all this means is that you should keep an eye on your packaging. Buy small bottles so you can use it all before it expires. Also look for opaque glass or plastic containers with a pump or some other air-restrictive device so you get the most for you money.

Now for the recommendations...
Kiehl's Powerful-Strength Line-Reducing Concentrate
An office favorite that dots many a Top Shelf. It's more creamy than liquid, which means it absorbs all the better. And skin is noticeably better almost immediately after applying.

Drunk Elephant C-Firma Day Serum
Ingredient purists will be happy with the contents of this serum—part of the Drunk Elephant M.O bans (blacklists, actually) known toxins. And it ticks all of the above boxes for good and safe packaging. The payoff is gradual—daily use improves skin tone and appearence of fine lines over weeks rather than days—but the large bottle lasts a good while. The results are good, and lasting.

Skinceuticals C E Ferulic
Worth it. Along with 15% vitamin C, there's vitamin E and ferulic in there (hence the name). Use it at night because it'll leave you with a tacky film on skin. A tacky film that makes you a beautiful angel with perfect skin.

Paula's Choice Resist C15 Super Booster
Say goodbye to all errant sun spots, dark marks, and scars from a youth spent not on the antioxidant train. People who use this product, worship at its altar. Tips: Keep it in the fridge to minimize smell (it's hot dog-scented) and make sure to wash your hands after you use it.

Photographed by Tom Newton.

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