Walk down any drugstore aisle and you'll find products plastered with words like "natural," "pure," and "clean." But here's the truth: these terms are largely unregulated. A product can call itself natural while still containing synthetic fragrances, petroleum derivatives, and harsh preservatives. So how do you know what's actually in your soap?
Here's a practical guide to reading soap labels — and knowing what to look for and what to avoid.
What to Look For
Plant-Based Oils as the Base
Truly natural soap starts with oils and butters. Look for recognizable names like olive oil (Olea europaea), coconut oil (Cocos nucifera), shea butter (Butyrospermum parkii), castor oil (Ricinus communis), or sunflower oil (Helianthus annuus). These are the building blocks of a quality natural bar, each bringing unique skin benefits.
Sodium Hydroxide (Lye)
Don't be alarmed if you see this on the label. Lye is a necessary part of the soap-making process — it's what turns oils into soap through a chemical reaction called saponification. Once the process is complete, no lye remains in the finished bar. Any true soap requires lye to be made.
Natural Colorants & Botanicals
Look for ingredients like kaolin clay, spirulina, turmeric, cocoa powder, rose clay, or dried botanicals. These give soaps their beautiful colours and added skin benefits without synthetic dyes.
Essential Oils
Fragrance should come from pure essential oils — distilled directly from plants. Common ones include lavender (Lavandula angustifolia), peppermint (Mentha piperita), and tea tree (Melaleuca alternifolia).
What to Avoid
"Fragrance" or "Parfum"
This single word on an ingredient list can hide dozens of undisclosed synthetic chemicals. Manufacturers are not required to disclose the individual components of a fragrance blend. If a soap lists "fragrance" without specifying it's from essential oils, it almost certainly contains synthetic fragrance.
Sodium Lauryl Sulfate (SLS) & Sodium Laureth Sulfate (SLES)
These are foaming agents commonly found in commercial soaps and shampoos. They're known skin irritants and can strip your skin's natural moisture barrier, leading to dryness and sensitivity.
Parabens
Preservatives like methylparaben, propylparaben, and butylparaben are used to extend shelf life. There is ongoing concern about their potential to disrupt hormones — at Aquinas Soap Company, we rely on natural preservatives instead.
Synthetic Dyes (FD&C or D&C Colors)
If you see a colour followed by a number (e.g. Red 40, Blue 1), it's a synthetic dye with no skin benefit and potential irritation risk.
Petroleum Derivatives
Ingredients like mineral oil, petrolatum, and paraffin are derived from petroleum. They can create a barrier on skin that blocks pores and prevents it from breathing naturally.
Our Promise at Aquinas Soap Company
Every product we make uses only natural, ethically sourced ingredients — no synthetic fragrances, no harsh sulfates, no petroleum derivatives, and no unnecessary additives. We believe transparency matters, which is why we list every ingredient clearly so you always know exactly what you're putting on your skin.
Ready to make the switch to truly natural soap? Explore our full bar soap collection and find your perfect bar.