Essential oils are one of the most common causes of contact dermatitis and skin sensitisation in skincare. Despite their association with natural or botanical formulation, they are also among the most significant fragrance allergens in cosmetics.
At Oath Co, we don’t use essential oils in any formula. This is a deliberate formulation decision, and one that shapes every product we create.
What are essential oils?
Essential oils are concentrated volatile aromatic compounds extracted from plants — typically through steam distillation or cold pressing. They are what give plants their characteristic scents: lavender, eucalyptus, rose, peppermint, tea tree.
They are not oils in the conventional sense. They are complex mixtures of dozens of individual chemical compounds, many of which are known irritants and allergens.
Why are essential oils a concern?
The issue with essential oils in skincare isn’t the plants they come from. It’s the concentration and the specific compounds they contain.
Many essential oils contain terpenes, aldehydes, and other volatile compounds that are recognised skin sensitisers. Repeated exposure to sensitising compounds can cause the immune system to develop a reaction — meaning a person may tolerate a product initially and develop a sensitivity over time.
This is particularly relevant for people with sensitive skin, eczema, or compromised barrier function — the same people most likely to reach for botanical skincare.
Why does Oath Co leave them out?
Our formulation philosophy begins with purpose. Every ingredient in an Oath Co formula is there because it serves a clear function: to nourish, condition, protect, or support the skin.
Essential oils would serve one purpose in our formulas: scent. And scent is not something we formulate for.
By leaving essential oils out entirely, we reduce the risk of sensitisation, support skin barrier function, and create products that are genuinely suitable for sensitive, reactive, and compromised skin — including babies, pregnant women, and those with easily irritated or reactive-prone skin.
It also means our formulas smell like what they are: carefully selected botanical oils, not a fragrance profile layered on top.
What about fragrance more broadly?
Oath Co products are also fragrance-free in the broader sense — we add no parfum, fragrance blends, or synthetic scent compounds of any kind. Our fragrance-free and essential oil-free standard applies across every collection we make.