What Is Dilauryl Thiodipropionate?
Dilauryl Thiodipropionate, sometimes listed on labels as Didodecyl 3,3′-thiodipropionate, is a synthetic ingredient created by linking two lauryl (coconut-derived) alcohol chains to a tiny sulfur-containing backbone called thiodipropionic acid. The result is a waxy, off-white powder that dissolves well in oils and melts at skin temperature.
The compound was first explored in the 1960s by chemists looking for ways to slow down the spoilage of fats and oils in food and cosmetics. Its strong ability to protect oils from turning rancid quickly caught the attention of the beauty industry, and it has been used in creams and lotions ever since.
Manufacturing starts with lauryl alcohol, usually sourced from coconut or palm kernel oil. This alcohol is reacted with thiodipropionic acid in the presence of an activating agent, forming the final ester. After purification and drying, the ingredient is milled into a fine powder that blends easily into oil phases during product compounding.
You are most likely to find Dilauryl Thiodipropionate in products rich in plant oils or butters that need a longer shelf life, such as moisturizers, body butters, lip balms, anti-aging serums, sun care lotions and rinse-off hair masks.
Dilauryl Thiodipropionate’s Cosmetic Benefits/Uses
This ingredient is valued for a single but important role in formulations.
As an antioxidant, Dilauryl Thiodipropionate helps keep the natural oils in a product from breaking down when exposed to air, light or heat. By slowing oxidation it prevents unpleasant odors, color changes and texture shifts, which in turn helps the product stay effective and pleasing to use for longer.
Who Can Use Dilauryl Thiodipropionate
This antioxidant is considered gentle enough for all major skin types including dry, oily, combination and sensitive because it does not act on the skin itself, only on the oils in the formula. People with highly reactive or allergy-prone skin may still want to keep an eye on the full ingredient list since the product base, not the antioxidant, is more likely to trigger issues.
Dilauryl Thiodipropionate is synthesized from lauryl alcohol that originates from coconut or palm kernel oil but the final molecule is produced entirely through lab processing with no animal-derived matter. That makes it suitable for vegans and vegetarians provided the finished product is also free of animal ingredients and not tested on animals.
The available safety data show no specific concerns for pregnancy or breastfeeding. That said this information is educational not medical advice and anyone who is pregnant or nursing should ask a healthcare provider before introducing new skincare products.
The ingredient is not known to cause photosensitivity so it will not make skin more prone to sunburn. It also plays well with common actives like retinol or vitamin C because its role is confined to protecting oils rather than altering skin function.
Potential Side Effects/Adverse Reactions
Responses to topical Dilauryl Thiodipropionate can vary from person to person. The points below outline potential issues but they are uncommon when the ingredient is used at the low levels typical in cosmetics and when the formula has been made correctly.
- Mild skin irritation – Rare stinging or redness may occur in very sensitive individuals
- Allergic contact dermatitis – Extremely uncommon but possible in people allergic to the molecule or its trace impurities
- Eye irritation – May cause watering or discomfort if the product accidentally gets into the eyes
- Acne flare-up in some users – While its comedogenic rating is low, heavy formulations containing this antioxidant could still clog pores in acne-prone skin
If any irritation, rash or discomfort appears stop use and consult a healthcare professional if symptoms persist or worsen
Comedogenic Rating
Rating: 1 out of 5. Dilauryl Thiodipropionate is an oily ester yet it is typically used at very low levels, usually under 0.2 percent of a formula, where it stays dissolved in the oil phase rather than sitting on the skin surface. Its molecular size is large and it is not highly occlusive, both factors that limit its ability to block pores. For most acne-prone users this makes the ingredient unlikely to trigger breakouts, though heavier balms or butters that contain it could still feel greasy on very oily skin. No published data link the compound itself to comedogenic reactions, which supports the low score.
Summary
Dilauryl Thiodipropionate is mainly an antioxidant that shields plant oils and butters from turning rancid by neutralizing oxygen-driven reactions. By preserving the integrity of these lipids it helps keep textures smooth, scents fresh and active ingredients stable throughout a product’s shelf life. Although effective it is not a headline act like retinol or niacinamide, so it appears quietly in the ingredients list of niche formulations rather than dominating mainstream launches. Current safety reviews classify it as low risk for irritation or sensitization when used at the concentrations allowed in cosmetics. Still, everyone’s skin is different, so doing a small patch test when trying a new product containing Dilauryl Thiodipropionate is a simple way to check personal tolerance.