WhySkin
The Journal
Skin Type vs. Skin Concern: Why the Difference Matters
Skin type shapes your cleanser and moisturizer format; skin concern shapes your active ingredients. Confusing the two leads to mismatched routines.
Co-Washing Explained: When to Skip Shampoo
How co-washing actually cleans hair, why curly/coily and high-porosity hair tend to benefit while fine or oily-scalp hair usually doesn't, and how to transition into it.
How to Read the PAO Symbol on Your Skincare Products
That open-jar icon with a number and an "M" isn't a printed expiration date. Here's what the PAO symbol actually means and how to turn it into a real expiry date.
Adjusting Your Foundation Shade Through the Seasons
Foundation depth needs rechecking as sun exposure changes through the year. Here's how to track that shift, re-test undertone and depth, and use sunscreen to manage how much shade change actually happens.
Sunscreen for Every Skin Tone: Avoiding the White Cast
A white or grey cast keeps a lot of people from wearing sunscreen consistently. Here's why it happens and how tinted formulas fix it for any skin tone.
Patch Testing New Products: A Step-by-Step Method
How to patch test a new skincare product properly — where, how long to wait, and what a reaction actually means before it reaches your face.
Why Skincare Needs Preservatives (And What the Common Ones Do)
Most water-based skincare needs a preservative system to stay safe over weeks of repeated use. Here is what phenoxyethanol and parabens actually do, and what preservative-free claims usually really mean.
Caring for Color-Treated Hair: What Changes
Sulfate-free cleansers, UV and heat protection, purple/blue shampoo toning, and pool-water habits that keep color-treated hair looking fresh between appointments.
How to Buy Foundation Online Without Testing It First
Buying foundation sight unseen doesn't have to be a gamble. Here's how to use undertone and depth as reliable inputs, and how to read shade-range swatch photos critically.
Using Samples and Minis to Test Before You Commit
A $45 serum that doesn't work out is an expensive lesson. Here's how a patch test plus a 2-4 week sample trial saves money before you buy full size.
Chemical vs. Mineral Sunscreen: How to Choose
Chemical and mineral sunscreens protect skin differently and feel different going on. Here's how each works and how to decide which fits you.
How Your Skin Type Changes With the Seasons
Why skin type shifts with humidity and indoor heating, and why retaking a skin type quiz each season keeps a routine matched to reality.