Omega-3 Fatty Acids Reduce Atopic Dermatitis Risk Despite Genetic Predispositions

Rui Mao

Credit: loop.frontiersin.org

New findings suggest higher plasma omega-3 is associated with reduced atopic dermatitis risk, and even among those with high genetic predispositions, increasing omega-3 and non-DHA omega-3 levels substantially mitigates risk of atopic dermatitis.¹

This analysis—which set out to evaluate the link between circulating fatty acids, genetic risk factors, and atopic dermatitis among adults—was authored in part by Rui Mao, from the Department of Dermatology at Central South University’s Xiangya Hospital in Changsha, China.

“Thus far, meta-analyses of [genome-wide association studies] have identified 16 [single-nucleotide polymorphisms] linked to specific plasma [fatty acids],” Mao and colleagues wrote. “Nevertheless, it remains to be explored whether these variants alter the effect of a particular [fatty acids] on [atopic dermatitis] risk.”^1,2

Analyzing Omega-3 Fatty Acid Impact on Atopic Dermatitis Risk

The investigators looked at data from 274,100 individuals featured in the UK Biobank who had available plasma fatty acid (FA) measurements at baseline. There were 268,589 participants who remained after excluding those with diagnosis of atopic dermatitis at baseline, for the assessment of the relationship between plasma fatty acid levels and risk of the skin disease.

After excluding an additional 18,549 individuals due to incomplete or mismatched genetic data, as well as non-white British ancestry, the investigative team was left with a final cohort of 250,040 individuals for their analysis. The team randomly selected baseline plasma samples, totaling approximately 280,000, for the purposes of fatty acid level detection.

Given their aim of ensuring biomarker reliability, the investigators carried out repeated evaluations between 2012 - 2013, seeking to confirm the stability of the measured fatty acids. An assessment of various fatty acid categories was implemented, with the team looking at monounsaturated fatty acids, saturated fatty acids, omega-3, omega-6, polyunsaturated fatty acids, docosahexaenoic acid (DHA), non-DHA omega-3, linoleic acid (LA), and non-LA omega-6.

To control for potential confounders, several covariates were incorporated. Examples of such covariates include body mass index (BMI), sex, Townsend deprivation index, age, lipid drug use, level of educational attainment, income, alcohol intake, smoking status, level of physical activity level, and dietary supplement consumption.

The research team identified participants’ diagnoses via the International Classification of Diseases, drawing from hospital as well as primary care data. In terms of the primary outcome of interest, the team tracked atopic dermatitis incidence from the point of baseline until loss to follow-up, until the first recorded diagnosis of atopic dermatitis, until death, or until the study cutoff date in July 2023. They also evaluated atopic dermatitis genetic risk among subjects through the use of a polygenic risk score (PRS) based on data from the largest atopic dermatitis-associated genome-wide association studies.

Overall, the investigators’ findings revealed an inverse association between the plasma omega-3 levels of participants and their atopic dermatitis risk, with a hazard ratio (HR) of 0.93 (95% confidence interval [CI]: 0.89–0.98). This was also noted as independent of participants’ genetic susceptibility.

The lowest risk of atopic dermatitis was exhibited by individuals who had both low genetic risk and high omega-3 levels, with a 38% reduction in risk observed by the research team compared to the reference group. Additionally, the team reported that subjects carrying GA/AA genotypes on rs1692120 were noted as having a significantly increased risk of the skin disease.

However, the investigative team further highlighted that participants showing a greater number of A alleles for rs174448 had a substantially diminished risk of atopic dermatitis (both P trends < .05). The data, all in all, suggest that raising intake of omega-3s may serve as a preventive strategy against atopic dermatitis.

“Our findings suggest that increasing the intake of omega-3 should be used as a measure to prevent [atopic dermatitis], and tailoring prevention strategies to individual genetic predispositions can improve the effectiveness of interventions,” they wrote.¹

References

1. R. Mao, X. Meng, T. Zhang, F. Wang, Y. Zhong, J. Li, Evaluating the Impact of Omega-3 Fatty Acids and Genetic Susceptibility on Atopic Dermatitis in Adults. Mol. Nutr. Food Res. 2025, e70002. https://doi.org/10.1002/mnfr.70002.

2. R. N. Lemaitre, T. Tanaka, W. Tang, et al., “Genetic Loci Associated With Plasma Phospholipid n-3 Fatty Acids: A Meta-analysis of Genome-Wide Association Studies from the CHARGE Consortium,” PLoS Genetics 7, no. 7 (2011): e1002193.