Helianthus Annuus (Sunflower) Seed Oil

What it is

Sunflower seed oil is pressed from the seeds of Helianthus annuus and is one of the most common carrier oils in skincare. Conventional sunflower oil is roughly 55 to 70% linoleic acid, the essential fatty acid that skin uses to build the acylceramides that hold the barrier together; high-oleic cultivars invert that ratio to around 80% oleic acid. Formulators use it because it is cheap, light on the skin, and a good solvent for oil-soluble ingredients such as vitamin E.

What it does well

• Preserves the skin barrier rather than damaging it

  In a randomised forearm-controlled study in adults, four weeks of twice-daily sunflower seed oil maintained stratum corneum integrity, caused no redness and improved hydration, while olive oil applied to the other arm of the same volunteers significantly damaged the barrier.

  Moderate evidence

• Supplies linoleic acid, which is relatively scarce in acne-prone skin

  People with acne have consistently been shown to have low linoleic acid in their surface lipids, and the leading hypothesis is that this creates a local essential fatty acid deficiency in the follicle wall that drives hyperkeratosis. Whether topping it up topically changes acne outcomes has not been convincingly demonstrated.

  Limited evidence

• Cheap, light and well tolerated

  Sunflower oil sinks in quickly and is widely used in products for sensitive and eczema-prone skin, including in neonatal care in low-resource settings. Contact allergy is rare.

  Moderate evidence

Worth knowing

• Two very different oils share the same INCI name

  'Helianthus Annuus (Sunflower) Seed Oil' covers both the high-linoleic type and the high-oleic type, which behave differently on the skin and have opposite stability profiles. The label will not tell you which one you are getting.

  Matters most toPeople choosing an oil specifically for its linoleic acid content.

• Not a good idea on very immature skin

  In a randomised trial in premature infants, daily sunflower seed oil for the first ten days was followed by a significant rise in water loss through the skin and falling hydration, suggesting it may slow rather than help barrier maturation. Findings in full-term and adult skin have been more favourable, but this is a real counterweight to the idea that plant oils are automatically gentle.

  Matters most toParents and carers of premature or newborn infants.

• Oxidises relatively quickly

  The polyunsaturated fatty acids that make it useful also make it prone to going rancid, which is why it is almost always supplied with added tocopherol. An oil that smells sharp or like old crayons should be discarded.

  Matters most toAnyone keeping oils or oil-rich masks open for many months.

Where the EU stands

Sources (3)

Every link goes to the original: a journal, a PubMed record or an EU document.

1. [1]
   Effect of olive and sunflower seed oil on the adult skin barrier: implications for neonatal skin care

   Pediatric Dermatology · 2013 · doi:10.1111/j.1525-1470.2012.01865.x

   Sunflower seed oil preserved stratum corneum integrity and improved hydration without causing redness, whereas olive oil on the same volunteers significantly damaged the skin barrier.

2. [2]
   Influence of sunflower seed oil on the skin barrier function of preterm infants: a randomized controlled trial

   Dermatology · 2014 · doi:10.1159/000363380

   Daily sunflower seed oil in premature infants was followed by significantly increased water loss through the skin and falling hydration, suggesting it may retard postnatal barrier maturation.

3. [3]
   Essential fatty acids and acne

   Journal of the American Academy of Dermatology · 1986 · doi:10.1016/s0190-9622(86)70025-x

   Proposed that low linoleic acid concentrations in sebum create a local essential fatty acid deficiency in the follicle wall, driving the hyperkeratosis that forms comedones.