Is Natural Soap Actually Better For Your Skin Than Shower Gel?
We make soap, so take that as read. But we looked at the actual evidence before writing this rather than just asserting the obvious. Here's what holds up.
A shorter, more honest formula
Shower gel is mostly water, typically 70 to 80% of the bottle.[1] Because it's water-based, it needs a preservative system to stop it going off in your bathroom. There's nothing wrong with that in principle, but it's why the ingredients list on a bottle of shower gel usually runs long: surfactants, thickeners, humectants, preservatives, stabilisers, on top of whatever's giving it colour and scent.
A cold-pressed soap bar is a different structure entirely. Once cured, a soap bar's water is chemically bound up in the bar itself rather than sitting free, which is why bar soap has what chemists call low water activity. Bacteria and mould can't get a foothold, so a proper soap bar doesn't need a preservative system at all.[2] That's not a formulation trick. It's a direct result of being solid.
Fewer functional ingredients, doing fewer jobs, is a straightforwardly simpler thing to put on your skin.
Skin cells didn't disagree either
A 2025 study directly compared natural soap compounds against sodium lauryl sulfate (SLS), a detergent common in shower gel, using human skin cell cultures. The natural soap compounds were significantly less toxic to those cells after prolonged exposure.[3] Worth flagging: the study was funded by a soap manufacturer, so we're not treating it as the last word. But it's a real, peer-reviewed lab result, and it points the same direction as the formulation difference above, not away from it.
The pH warning you'll read everywhere doesn't quite apply to us
Most of the dermatology caution about soap comes down to pH. Natural soap sits at an alkaline pH, usually somewhere between 8.5 and 11, while skin's own surface is closer to 5.[4] That gap is real, and it's the basis for most "soap is bad for your skin" advice you'll find online.
But look closer at what that advice is usually testing, and it's mass-market bar soap, the kind that's had its glycerin extracted and sold separately to other industries, leaving a harsher, more stripped-back bar behind. Cold-pressed soap, made the traditional way, keeps its glycerin in. Glycerin is a humectant, it draws moisture to the skin rather than away from it, and it's a large part of why cold-pressed bars don't behave like the stripped-down soap the pH warnings are usually describing.[5] Skin also buffers itself back to its normal pH fairly quickly after washing with most things, cold-pressed soap included.
Where the real argument sits
Here's the case we'd actually stand behind. Shower gel isn't simpler than soap, it's more complex: more ingredients, more of them synthetic, and reliably built around "parfum," a single word that can legally hide dozens of undisclosed fragrance compounds, some of them known irritants.[6] Natural soap's ingredient list is short by nature, not by marketing choice, and scenting from a named essential oil is at least honest about what's in the bar, even though essential oils carry their own, separately declarable allergens and aren't automatically risk-free either.[6]
That's not a claim that soap cleans better. It's a claim that there's simply less to go wrong with fewer, more legible ingredients doing the job, and on that basis, the added complexity of a syndet shower gel makes it the harder one to defend, not the safer one.
Where that leaves you
Read the label either way. Short, recognisable ingredients beat a single word doing the hiding, whichever format you reach for. We just think, on the evidence, soap has the simpler case to make.
By James Allan. Reviewed 19 August 2026.
Sources
- Cosmetic chemistry reference on shower gel water content and preservative requirements
- Formulation science reference on solid soap water activity and preservative-free stability
- 2025 in-vitro study comparing natural soap compounds and SLS on human skin cell cultures (soap-manufacturer funded)
- Dermatology reference on skin surface pH versus soap pH
- Molecules, 2018, cold saponification chemistry and glycerine retention in traditional soap
- SGS, "EU Changes to Cosmetic Allergen Rules" (Regulation 1223/2009, as amended by 2023/1545)