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Clear Skin, Naturally—Every Day Starts with Castile

Prep U’s Castile Bars deliver gentle, plant-based cleansing for teens and active skin. Tackle breakouts, sweat, and sensitive skin—no harsh chemicals, just pure, effective care.

Ingredient Spotlights & “What to Avoid” Guides: The Smart Teen’s Guide to Skincare Ingredients

Why Ingredients Matter—Especially for Teens

Ever look at a skincare label and feel like you’re reading a different language? You’re not alone! With so many products out there, it can be tough to know what’s actually good for your skin—and what could cause irritation, breakouts, or worse. For teens, whose skin is often more sensitive or acne-prone, understanding ingredients is super important. The right ingredients can help you stay clear and confident. The wrong ones? Not so much.
Prep U is all about clean, plant-based, and effective skincare—made for real teen skin. Here’s your go-to guide for ingredient spotlights (what to look for), “what to avoid” (the stuff you don’t want in your routine), and why our standards go beyond what’s required in the US.

The EU vs. US Ingredient Gap: Why It Matters

Did you know the European Union bans or restricts over 1,700 chemicals from personal care products, while the US FDA restricts only about 11?
That means teens in the US are exposed to hundreds of ingredients that Europe considers too risky for your skin and health, including some linked to cancer, hormone disruption, or allergies.
At Prep U, we don’t wait for the US to catch up. We voluntarily follow the strictest global standards—if it’s not safe for the EU, you won’t find it in our products.

Common Ingredients Banned in the EU (but Allowed in the US):

  • Parabens (certain types)
  • Formaldehyde & formaldehyde-releasing preservatives
  • Phthalates
  • Triclosan
  • Coal tar dyes
  • Hydroquinone
  • Toluene
  • Sodium Lauryl Sulfate (SLS) & Sodium Laureth Sulfate (SLES)
  • Butylated Hydroxyanisole (BHA) & Butylated Hydroxytoluene (BHT)
  • Polyethylene Glycols (PEGs)
  • Resorcinol
  • Ethanolamines (DEA, MEA, TEA)
  • Oxybenzone & Octinoxate (chemical sunscreen filters)
  • Aluminum compounds
  • Synthetic fragrances & parfum (which can hide hundreds of chemicals)
  • Mercury compounds


Ingredient Spotlights: The Good Stuff for Teen Skin

Tea Tree Oil

Why it’s great: A natural antibacterial and anti-inflammatory, tea tree oil helps fight acne-causing bacteria and calms redness.
Find it in: Tea Tree Cleansing Castile Bar

Activated Charcoal

Why it’s great: Binds to dirt and oil to deeply cleanse pores—perfect for oily or acne-prone skin.
Find it in: Charcoal Face & Body Cleansing Bar

Bentonite & French Green Clay

Why they’re great: Both clays absorb excess oil, detoxify, and help keep pores clear. French green clay is especially gentle and soothing.
Find them in: Alpine Shave Bar, Charcoal Bar

Shea Butter

Why it’s great: Deeply hydrates and soothes dry, sensitive, or irritated skin—no greasy feeling.
Find it in: All Prep U cleansing bars

Oats

Why they’re great: Gently exfoliate and calm red, itchy, or sensitive skin.
Find them in: Peppermint + Oats Cleansing Bar

Olive & Coconut Oil

Why they’re great: Nourish, moisturize, and support a healthy skin barrier.
Find them in: All Prep U bars

Essential Oils 

Why they’re great: Provide natural scent, add calming or clarifying benefits, and are much gentler than synthetic fragrances.

What to Avoid: Ingredients That Don’t Belong in Teen Skincare

Parabens

Preservatives linked to hormone disruption and potential carcinogenic effects. Banned in the EU, still found in many US products.

Sulfates (SLS, SLES)

Harsh foaming agents that can strip natural oils and irritate skin. EU restricts; US does not.

Phthalates

Plasticizers often hidden in “fragrance.” Linked to hormone disruption and allergies.

Formaldehyde & Formaldehyde-Releasers

Known carcinogens and skin irritants, banned in the EU, but still used in US products as preservatives.

Triclosan

Antibacterial agent linked to hormone disruption and banned in the EU.

Synthetic Fragrances & Dyes

Can include hundreds of undisclosed chemicals, many of which are banned in the EU for causing allergies, hormone disruption, or other health risks.

BHA & BHT

Preservatives banned in the EU due to links with cancer and hormone disruption.

Aluminum Compounds

Used in antiperspirants, linked to neurotoxicity and breast cancer concerns.

Mercury Compounds

Neurotoxic ingredients banned in most countries, including the EU, but still found in some products elsewhere.

How to Read a Skincare Label Like a Pro

  • Look for short, simple ingredient lists. If you can pronounce most of it, that’s a good sign!
  • Check for plant-based oils, clays, and butters high up on the list.
  • Avoid products with “fragrance” or “parfum” unless it’s from natural essential oils.
  • When in doubt, patch test: Try a new product on a small area before using it on your whole face.

Prep U’s Ingredient Promise

Every Prep U product is made without parabens, sulfates, phthalates, formaldehyde, synthetic fragrances, dyes, aluminum, mercury, or animal byproducts. We’re Leaping Bunny certified, cruelty-free, and always transparent about what’s inside.
We go beyond US standards—our formulas are EU-safe, even though it’s not required. Because teens deserve better.

FAQs: Teen Skincare Ingredients

Why does Prep U avoid parabens and sulfates?
We want your skin to be as healthy as possible—no harsh or hormone-disrupting chemicals here!
Are all Prep U products vegan and cruelty-free?
Yes! We never use animal products or test on animals.
Can natural ingredients cause breakouts?
Everyone’s skin is different, so always patch test. But Prep U’s plant-based formulas are designed to be gentle and effective for teen skin.

Related Resources


Smarter Skincare Starts with Ingredients     

Prep U helps you take control of your skin with clean, effective, and trustworthy ingredients. Shop all Prep U skincare or take our skin quiz to find your perfect match!

 


Prep U Promise:


You’ll never find these ingredients—or any other EU-banned chemicals—in our bars, washes, or deodorants. We believe in clean, plant-based, and transparent formulas for every teen.


References:
Loading image: A creamy bar of tea tree soap surrounded by foamy bubbles, creating a fresh and clean atmosphere. A creamy bar of tea tree soap surrounded by foamy bubbles, creating a fresh and clean atmosphere.

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