The investigative study, which was funded by multinational FMCG company Unilever, has reviewed a range of studies, including internal Unilever research and data, PubMed/Medline studies and Google searches.
The research encompassed over 55,000 articles published between 1857 until 2025 investigating the role of omega-3 polyunsaturated fatty acids, specifically DHA and EPA, in actively resolving skin inflammation.
The study focused on the pro-resolution mechanisms, across in vitro (cell-based experiments), in vivo (animal models and clinical assessments), and human trials.
The researchers said they aimed evaluate the potential of DHA and EPA as natural, bioactive ingredients in cosmetic formulations to reduce inflammation, enhance barrier integrity, and promote skin recovery.
The team noted that skin injury by severe trauma or pathogens, UV exposure and personal care activities like shaving, can lead to the release of proinflammatory chemical mediators resulting in acute skin inflammation, signs of which can include redness, heat, swelling and pain, and loss of function.
The research team noted that this initial response “is needed to contain the inflammation and protect the host and is characterised by activation and recruitment of leucocytes that need to remove cellular debris from the site of inflammation.”
However, they explained that this inflammation needs to be resolved to prevent the inflammation from spreading or becoming chronic, as chronic inflammation can lead to disease, and that this active pro-resolution process involves chemical mediators released by the cells which help the skin return to homeostasis.
Polyunsaturated fatty acids (PUFAs), especially n-3 PUFAs, like DHA and EPA, naturally found in the cell membrane in the form of phospholipids, ensure skin is able to properly resolve inflammation and repair damage.
Deactivates inflammation, supports barrier, heals wounds
The research suggested that DHA and EPA are precursors to specialised pro-resolving mediators: resolvins, protectins, and maresins, which actively deactivate inflammation rather than just suppress it.
These specialised pro-resolving mediators reduce neutrophil infiltration, encourage macrophage phagocytosis of cellular debris, promote tissue repair, and restore the homeostasis of the skin.
The research also detailed the anti-inflammatory and barrier benefits, including attenuation of UV and pollution damage: DHA/EPA reduce expression of pro-inflammatory cytokines (e.g., IL-1β, IL-6, TNF-α), cyclooxygenase-2 (COX-2), and oxidative stress markers induced by UV and environmental pollutants.
There are also benefits for barrier support, as DHA/EPA enhance lipid barrier function, hydration, and help recover compromised skin post-stressor exposure.
Along with wound healing benefits from both topical and ingestible DHA supplementation, which accelerates wound closure and tissue regeneration.
Some notable findings included that oral intake of fish oil (12 g of EPA/day) improved psoriasis severity, including erythema and scaling, while one controlled trial undertaken by Unilever found that dietary fish oil reduced biomarkers of skin inflammation (IL-1α, oxidative stress) and mitigated the impact of pollution from PM2.5 exposure.
Decreased UV-induced epidermal thickening, preserved collagen, reduced MMPs
More research the team analysed found that topical DHA decreased UV-induced epidermal thickening, preserved collagen, and reduced Matrix metalloproteinases (MMPs) activity – a key enzyme that degrades the extracellular matrix.
Combined treatment with DHA/EPA and microneedling enhanced skin luminosity, redness reduction, and texture improvement.
DHA/EPA also decreases pro-inflammatory cytokines in macrophage models following lipopolysaccharide stimulation, and increased resolvin E1 production confirms active resolution pathways to fight inflammation.
Meanwhile, clinical imaging also showed significance in skin brightening and erythema reduction after prolonged supplementation with the nutrients.
Takeaways for skin care brands for future NPD
Overall, the research team concluded that evidence indicates that DHA and EPA, through their conversion into SPMs, actively facilitate the resolution of skin inflammation caused by UV, pollution, or injury. They also support skin barrier function, reduce erythema, and promote wound healing.
These findings support the development of natural, pro-resolution ingredients for formulations targeting inflammatory skin conditions like eczema, psoriasis, and acne, and photoaging.
Combining DHA/EPA with other antioxidants or skin barrier agents can enhance anti-inflammatory and skin-repair benefits. Both systemic and topical delivery modes merit further exploration.
