journal

Should You Use Vitamin C Serum in the Morning o...

Should you use vitamin C serum in the morning or at night? Learn the best time to apply vitamin C, how to layer it with sunscreen, retinol and niacinamide, and...

Why Does Vitamin C Serum Sting or Burn? When It...

Does vitamin C serum sting your face? Learn why vitamin C can tingle or burn, when mild tingling may be normal, signs of irritation, and how to use vitamin C...

Why Does Vitamin C Serum Turn Yellow or Brown? ...

Did your vitamin C serum turn yellow, orange or brown? Learn why vitamin C serum changes color, how to tell if it has oxidized, whether you should still use it,...

How Often Should Beginners Use Retinol? A Simpl...

How often should beginners use retinol? Learn how many nights per week to start, when to increase retinol use, signs you're using too much, and how to build a beginner-friendly...

How to Use Glycolic Acid Serum Without Over-Exf...

Learn how to use glycolic acid serum safely, how often beginners should apply it, what products to avoid mixing with it, and how to recognize signs of over-exfoliation.

Can You Use Two Serums at the Same Time? How to...

Can you use two serums at once? Learn which serums can be layered, which combinations may irritate skin, what order to apply them in, and when one serum is enough.