Mechanistic insights and clinical evidence of Helianthus annuus Linn. (Sunflower) seed oil for dermatological applications: A narrative review.

Plant oils play an important role in natural product-based dermatological formulations owing to their multifunctional therapeutic properties. Among these, sunflower seed oil (SSO) has gained prominence due to its dual role as a barrier-restoring emollient and skin penetration enhancer. Rich in unsaturated fatty acids, particularly linoleic acid (LA) and oleic acid (OA), SSO supports skin health by restoring lipid bilayer organization, modulating ceramide synthesis, and activating peroxisome proliferator-activated receptor-alpha (PPAR-α). These mechanisms reinforce barrier integrity while facilitating transdermal delivery of active agents. However, oils high in OA and/or containing protein allergens may compromise barrier function and promote allergen penetration, necessitating careful evaluation of chemical composition and structural characteristics. Ex vivo studies using porcine skin models have demonstrated SSO ability to enhance the permeation of both hydrophilic and lipophilic compounds. Clinically, SSO has shown efficacy in reducing transepidermal water loss (TEWL), improving hydration, and accelerating wound healing in conditions such as xerosis and atopic dermatitis. Its favourable safety profile, biocompatibility, and successful incorporation into various dermatological and cosmeceutical formulations underscore its versatility. This review critically examines the molecular interactions between SSO and the skin barrier, with specific focus on its roles in barrier restoration, inflammation modulation and transdermal enhancement. Mechanistic insights from its fatty acid composition are integrated with ex vivo findings, supported by clinical evidence, to evaluate its therapeutic potential and utility as a multifunctional, plant-based excipient in modern topical drug delivery systems for human skin health.