What is superfat in soap, and why is it important?
" Surgras " in a bar of soap refers to the fraction of vegetable oils or butters that has not been saponified—that is, that remains in the bar of soap in the form of active lipids after the manufacturing process. It is this excess of fatty substances that gives superfatted soap its nourishing and protective properties, which set it apart from ordinary soap.
- A conventional soap has a superfat content of 0–3%—effective for cleansing, but it can dry out sensitive skin
- Handcrafted superfatted soap has a content of 5–10%—the unsaponified oils remain active on the skin and partially compensate for the lipid loss caused by cleansing
- Above 10–12%: risk of rancidity in the unsaponified fraction—less favorable for shelf life
- Note: A superfatted soap always has an alkaline pH (8–10) because it remains a true soap—the superfatting compensates for but does not correct the pH
- For a physiological pH of 5.5 plus a superfatting effect: choose a superfatted solid syndet—see our solid soap page
Which superfatting fats make a difference in soap?
Not all superfatting agents are created equal—their fatty acid profile determines their effectiveness on the skin.
- Unsaponified shea butter: rich in unsaponifiables (avocatin, phytosterols)—active ingredients that effectively support the skin barrier and dry skin —the most valuable superfatting agent
- Avocado oil: omega-3, abundant unsaponifiables—for mature and very dry skin—an excellent superfatting agent for high-end soaps
- Sweet almond oil: oleic and linoleic acids—a light, well-tolerated emollient—well-tolerated by sensitive skin and children
- Castor oil (in small quantities): hydrophilic ricinol — increases lather and helps the soap adhere to the skin — often found in small amounts in artisanal superfatted soaps
- Lanolin: a lipid similar to human skin lipids—unmatched for very dry skin but allergenic for some—skin patch test recommended
What are superfatted soaps used for, and for which skin types?
Surgras soap is a versatile product—but its suitability depends on your skin type.
- Dry skin on the body and hands: superfatted soap at 7–10% — daily cleansing without tightness — follow up with a body cream while skin is still damp after rinsing
- Mild atopic skin: superfatted soap with colloidal oats or shea butter—acceptable if well tolerated—severe cases should use a dermatological syndet or a cleansing cream
- Infants and children: superfatted soap that is fragrance-free, free of essential oils, and specifically formulated for “babies”—check the stated superfatting percentage
- Oily skin: mild superfatted soap (5%) with jojoba oil — cleanses deeply without causing excessive imbalance — follow up with a sebum-regulating treatment
- Face: cold-processed superfatted soap—a viable option for normal to dry skin—reactive skin: opt for a cleanser formulated at physiological pH
How can you recognize a genuine, high-quality superfatted soap and store it properly?
- On the INCI list: “sodium [oil] saponified” + the presence of unsaponified oil in the list (e.g., “Butyrospermum parkii butter” or “Olea europaea”) — confirms the presence of a true superfatted soap
- The phrase “cold-processed” (cold process): an artisanal method that preserves unsaponifiable components — real added value for the active ingredients
- Declared superfatting percentage: the best artisanal brands specify this—between 5 and 8% is the optimal balance of quality and shelf life
- Storage: A well-draining soap dish is essential—surgras soap is more sensitive to water than conventional soap (the unsaponified lipid fraction is more fragile)
- See our personal care line
