Skin Signal, Your SPF|YI: Why Your Skin Acts Weird in September
Welcome to the first edition of Skin Signal, Your SPF|YI — where I share dermatologist-backed skincare tips, product picks I actually use, and insider hacks you won’t just stumble across on Google.
If you’ve ever wondered why your skin seems to shift gears in September, you’re not alone. Let’s dig in.
Why Your Skin Acts Weird in September
As summer fades, your skin is adjusting to new conditions — and not always in your favor. Here’s what’s happening:
Humidity drops → more transepidermal water loss, which means dryness, flaking, and irritation.
Indoor heating kicks on → even more dryness.
UV damage from summer lingers → pigmentation and redness can worsen.
Fall sun is sneaky strong → you still need daily SPF (yes, even when it’s cloudy or chilly).
Pro move: Start layering hydration now so your barrier is ready before winter. And whatever you do, don’t ditch your sunscreen just because “it’s not summer.”
Stay tuned: next month I’ll be sharing my top 3 fall moisturizers for maximum skin insurance.
Ingredient Spotlight: Ectoin
Lately, I’ve been asked: Should my moisturizer have ectoin?
Ectoin is a stress-protection molecule discovered in extremophiles (organisms that thrive in deserts and salt lakes). On skin, it helps shield against oxidative stress, pollution, blue light, and UV damage — all while keeping your barrier happy.
Why I love it:
Calms redness
Pairs beautifully with retinoids/retinols
Protects post-procedure skin
Works in harsh climates (like airplane air!)
How to use it:
AM: Layer under SPF for an extra defense boost
PM: Seal in moisture after retinoids or acids to reduce irritation
See ectoin products I recommend.
Derm Hack of the Month: Red Light Mask for Hair Growth
If you own a red light face mask, here’s a bonus trick: tilt it forward over your scalp for 5–10 minutes a few times a week.
Why it works:
Red light (630–680nm) penetrates the scalp, boosting blood flow and energizing hair follicles — the same principle behind FDA-cleared hair growth caps. Clinical studies show improved hair density and count after 12–16 weeks of use.
So next time you’re masking, give your scalp some love. Zero extra cost, big potential payoff.
Check out my full red light guide.
Inside My Routine: Travel Edition
By the time you’re reading this, I’ll be somewhere between a Seoul skincare shop and a bowl of Vietnamese pho. Travel skincare has to handle changing climates, dry airplane air, and (let’s be honest) hotel bathroom lighting.
Here’s what’s in my carry-on:
Cetaphil Gentle Skin Cleanser – gentle enough to use without water.
Hypochlorous Acid Spray – keeps skin calm and bacteria at bay.
Aquaphor – for lips, cuticles, and emergency dry patches.
Collagen Hydrogel Mask – my in-flight hydration boost.
Experiment’s Molecular Mesh Ectoin Cream – barrier protection for all the environmental changes.
Pimple Patches – because I always get at least one travel breakout.