One question I get asked frequently is why does your stuff cost more than store bought?

One of the many reasons I will tell you is because I avoid using Propylene Glycol in my products. Therefore, my products are several times more expensive to make. 

So what is Propylene Glycol? 

P.G. shows up everywhere—especially in lotions, whipped soaps, and pre-made glycerin soap bases. So let’s talk plainly about what it is and why I choose not to formulate with it.

Propylene glycol is a synthetic compound derived from petroleum.

In cosmetics, it’s used to hold moisture, improve slip and texture, dissolve fragrances and actives, stabilize formulas, and extend shelf life. It’s popular because it’s cheap, predictable, and effective—especially in large-scale manufacturing. But effective doesn’t automatically mean ideal for skin.

This part matters: propylene glycol is a well-documented skin irritant for a portion of the population. Not everyone reacts, but many do—especially with repeated exposure. It’s commonly associated with redness, stinging or burning, itchiness, dermatitis, and flare-ups in sensitive or compromised skin. Ironically, it’s often found in products marketed as “gentle” or “for sensitive skin” because it improves texture and feel, not because it supports the skin barrier.

Petroleum-derived ingredients aren’t automatically dangerous, but they’re designed for industrial efficiency, not biological compatibility.

Propylene glycol’s job is to push ingredients deeper into the skin, keep formulas uniform, and make production faster and cheaper. That penetration-enhancing quality is exactly why some skin types don’t tolerate it well. It doesn’t just help “good” ingredients absorb—it helps everything absorb.

Propylene glycol is extremely common in pre-formulated cosmetic bases. Those bases are designed to work for as many brands as possible, remain stable no matter what’s added, and reduce the need for advanced formulation skills. If you start from a base, you inherit whatever’s already inside it—including propylene glycol. I don’t use pre-made bases, so I don’t need propylene glycol.

When I formulate from scratch, I choose ingredients that support the skin barrier rather than override it. I rely on vegetable glycerin for hydration, plant oils and butters for structure and nourishment, and thoughtful emulsification instead of chemical shortcuts.

These ingredients take more work, they’re less forgiving, and they don’t come from petroleum—but they align with how skin actually functions.

This isn’t about fear.

Propylene glycol is allowed in cosmetics, and some people tolerate it just fine. I don’t use it because it’s petroleum-derived, it’s a known irritant for many skin types, it’s unnecessary when formulating properly, and it prioritizes manufacturing ease over skin biology.

My goal isn’t to follow industry norms—it’s to make products that people with sensitive, reactive, or tired skin can actually use long-term.

Every ingredient earns its place in my formulas. Propylene glycol doesn’t fit my standards because I don’t believe skin care should rely on petroleum-based irritants when gentler, skin-aligned options exist.

Your skin isn’t difficult. It’s just asking to be treated with intention.

— Molly 🫧