What Are The Effects of Caffeine On Your Skin?

The effects of caffeine on your skin depend on a few factors. They largely depend on they type of caffeine you're ingesting as well as creams, sugars, etc. Here are the basics:

Coffee Beans Themselves Are Packed With Antioxidants
Coffee has been shown to be a strong antioxidant, which basically means that it fights the free radicals that lead to premature aging in skin. This is a very good thing. Caffeine itself is actually an antioxidant as well. Caffeine is also effective when applied topically to the skin, as both an antixodant and vasoconstictor (shrinking blood vessels, reducing puffiness)

Caffeine & Under-eye Bags/Dark Circles
Dr. Jeannette Graf, a certified clinical and research dermatologist says: "Caffeine is a soothing, anti-inflammatory and vasoconstrictive, which can decrease redness and puffiness.
Dr. Kavita Mariwalla, a NY based dermatologist and dermatologic surgeon says: "Caffeine helps the microcirculation of blood in the skin, which is why it also helps decrease brown discoloration underneath the eyes, but only over the short term"
So, caffeine has been shown to perk up tired eyes & reduce puffiness but the effects are only temporary.

Acne - It can make your acne worse
Gary Goldenberg, assistant clinical professor of dermatology at Mt. Sinai Hospital says: "Caffeine doesn't cause acne. However, overconsumption of caffeine has been associated with stress, which is associated with acne." In other words, caffeine increases cortisol during stress, which leads to acne or worsening acne.