Vitamin C serums are legendary for a reason: They really work. Uneven skin tone, rough texture, fine lines, acne scars, general dullness — you can name just about any common complexion concern and there’s a good chance that vitamin C (and the skin-care products it’s featured in) is a recommended treatment.

How does the ingredient work on the skin, though? Are the brighter, smoother results thanks to the same potent antioxidant found in the orange juice you drink when you have a cold?