What Is Squalene?
Squalene is a natural hydrocarbon made up of six isoprene units whose chemical name is 2,6,10,15,19,23-hexamethyltetracosa-2,6,10,14,18,22-hexaene. It was first isolated in the early 1900s from shark liver oil, which remained the main commercial source for decades. As the beauty industry moved toward more sustainable practices most squalene used in cosmetics now comes from plant sources such as olives, sugarcane, rice bran and amaranth. Manufacturers extract the oil, purify it, then often hydrogenate it into squalane for added stability, though unmodified squalene is still valued for its lightweight feel.
Because it closely resembles the skin’s own sebum, squalene quickly became popular in moisturizers during the mid-20th century. Today it is produced through mechanical pressing or solvent extraction of the source oil followed by molecular distillation to remove impurities. Advances in biotechnology also allow fermentation of sugarcane to create high-purity, renewably sourced material.
You will most often find squalene in facial and body moisturizers, nourishing hair masks, anti-aging serums, after-sun treatments, lip balms and makeup formulations that aim for a dewy finish.
Squalene’s Cosmetic Benefits/Uses
Squalene serves several roles that enhance both skin and hair care products.
- Hair conditioning – coats the hair shaft with a light, non-greasy film that boosts softness, adds shine and helps tame frizz
- Emollient – fills the gaps between skin cells to smooth rough texture, prevent moisture loss and leave skin feeling supple
- Solvent – dissolves oil-soluble actives, fragrances and pigments which helps create stable formulations and improves the spreadability of the final product
Who Can Use Squalene
Squalene’s lightweight texture and skin-mimicking structure make it a good match for nearly every skin type including dry, normal, combination and sensitive skin. Oily or acne-prone users usually tolerate it well because it is non-occlusive and has a very low risk of clogging pores, though individual responses can vary.
Plant-derived squalene from olives, sugarcane or other botanical sources is suitable for vegans and vegetarians. If a label does not specify the origin there remains a small chance it could be sourced from shark liver oil so ethical shoppers should look for products that clearly state “vegetable squalene” or “100% plant derived.”
Current research shows no evidence that topical squalene poses a risk during pregnancy or while breastfeeding. Still this is not medical advice and anyone who is pregnant or nursing should review new skincare products with a qualified healthcare provider to be safe.
Squalene does not increase photosensitivity so it can be used in both day and night routines without raising the risk of sunburn. Because it is chemically stable in light and heat it also works well in travel or outdoor situations where temperatures fluctuate.
Potential Side Effects/Adverse Reactions
Reactions to topical squalene differ from person to person. The following is a list of potential side effects yet these outcomes are uncommon when the ingredient is properly formulated and used as directed.
- Contact dermatitis – a rare allergy presenting as redness itching or small bumps
- Breakouts or congestion – occasional in individuals who are highly prone to closed comedones despite the ingredient’s low comedogenic rating
- Irritation from oxidized product – squalene that has spoiled can smell rancid and may cause stinging or clogged pores
- Eye discomfort – mild burning or blurred vision if the product migrates into the eyes
If any of these reactions occur stop using the product and seek guidance from a healthcare professional.
Comedogenic Rating
Rating: 1 / 5
Squalene is structurally similar to the lipids your skin already produces so it spreads thinly and absorbs quickly rather than sitting on top of pores. Studies and user reports show a very low tendency to trigger comedones which is why it sits at a 1 instead of a 0. A small uptick in the score reflects the fact that, if the oil oxidizes, its thicker by-products can be slightly more pore clogging.
Because the rating is so low most people who are prone to acne can use it without problems.
Keep bottles tightly closed and away from heat or sunlight as fresh squalene is far less likely to cause congestion than a product that has gone rancid.
Summary
Squalene conditions hair, softens skin and acts as a solvent. Its molecular shape allows it to weave between cuticle layers on the hair shaft for extra gloss and slip, nestle into spaces between skin cells to smooth rough patches, and dissolve oil-based pigments or actives so formulas stay even and spreadable.
The ingredient’s popularity has risen sharply in the past decade thanks to sustainable plant sourcing and the trend toward lightweight oils that mimic natural sebum. You will now find it in everything from drugstore moisturizers to high-end serums.
Topically applied squalene is considered very safe, with allergies and breakouts reported only rarely. As with any new cosmetic it is wise to patch test first to make sure your individual skin agrees with it.