Higher docosahexaenoic acid proportions in blood are inversely associated with the prevalence of prediabetes: Evidence from the UK Biobank.

• Plasma docosahexaenoic acid (DHA) was inversely associated with prediabetes risk. • Plasma DHA was inversely associated with glycated hemoglobin A1c. • Prediabetes prevalence was highest with lowest plasma DHA proportions vs highest. • Prediabetics had lower DHA and total omega-3 fatty acid proportions in plasma. • Omega-3 fatty acids, especially DHA, may protect against prediabetes. Prediabetes and type 2 diabetes mellitus are growing global health concerns, predisposing individuals to various vascular complications. Lifestyle modifications, including dietary interventions, offer promising avenues for prevention and management. Using a multivariable-adjusted model, we analyzed the cross-sectional associations between plasma proportions (% of total fatty acids) of omega-3 polyunsaturated fatty acids (n 3 PUFA, including total n 3 PUFA, docosahexaenoic acid [DHA], non-DHA n 3 PUFA), and glycated hemoglobin A1c (HbA1c) as well as the prevalence of prediabetes in a sample from the UK Biobank cohort. Our hypothesis was that proportions of n 3 PUFA, especially DHA, would by inversely associated with the prediabetes prevalence. The sample (n = 92,762; 54.5% females) had an average age of 56 years and was overweight (mean body mass index = 27). The mean plasma DHA proportion in the sample was 2.03% (standard deviation [SD] = 0.67%), non-DHA n 3 PUFA was 2.41% (SD = 1.02%) and total n 3 PUFA was 4.43% (SD = 1.56%). Prediabetic individuals were identified by blood HbA1c proportions between 5.7% and 6.4% (39-46 mmol/mol) according to American Diabetes Association criteria. Each of the three n 3 PUFA biomarkers was inversely associated with HbA1c proportions. In particular, DHA showed the strongest inverse association, with an OR of 0.62 (95% confidence intervals: 0.58, 0.67; P <.001) when comparing quintiles 5 to 1 in a fully adjusted model. These findings suggest a potential protective role of n 3 PUFA, particularly DHA, in mitigating the risk of having prediabetes. Further prospective investigations are needed to clarify whether long-chain n 3 PUFA could function as modifiable factors for prediabetes. A cross-sectional analysis of the UK Biobank cohort found that lower plasma proportions of n 3 PUFA, especially DHA, were associated with a prevalence and odds of prediabetes. The prevalence of prediabetes was highest in individuals with the lowest DHA proportions (17.4%) compared to those with the highest (10.6%), suggesting a protective role of DHA against prediabetes. Abbreviations: DHA, docosahexaenoic acid; n 3 PUFA, omega-3 polyunsaturated fatty acids. [Display omitted] [ABSTRACT FROM AUTHOR]