Fatty acid biomarkers of dairy fat consumption and incidence of type 2 diabetes: A pooled analysis of prospective cohort studies

Abstract

BackgroundWe aimed to investigate prospective associations of circulating or adipose tissue odd-chain fatty acids 15:0 and 17:0 and trans-palmitoleic acid, t16:1n-7, as potential biomarkers of dairy fat intake, with incident type 2 diabetes (T2D).Methods and findingsSixteen prospective cohorts from 12 countries (7 from the United States, 7 from Europe, 1 from Australia, 1 from Taiwan) performed new harmonised individual-level analysis for the prospective associations according to a standardised plan. In total, 63,682 participants with a broad range of baseline ages and BMIs and 15,180 incident cases of T2D over the average of 9 years of follow-up were evaluated. Study-specific results were pooled using inverse-variance–weighted meta-analysis. Prespecified interactions by age, sex, BMI, and race/ethnicity were explored in each cohort and were meta-analysed. Potential heterogeneity by cohort-specific characteristics (regions, lipid compartments used for fatty acid assays) was assessed with metaregression. After adjustment for potential confounders, including measures of adiposity (BMI, waist circumference) and lipogenesis (levels of palmitate, triglycerides), higher levels of 15:0, 17:0, and t16:1n-7 were associated with lower incidence of T2D. In the most adjusted model, the hazard ratio (95% CI) for incident T2D per cohort-specific 10th to 90th percentile range of 15:0 was 0.80 (0.73–0.87); of 17:0, 0.65 (0.59–0.72); of t16:1n7, 0.82 (0.70–0.96); and of their sum, 0.71 (0.63–0.79). In exploratory analyses, similar associations for 15:0, 17:0, and the sum of all three fatty acids were present in both genders but stronger in women than in men (pinteraction < 0.001). Whereas studying associations with biomarkers has several advantages, as limitations, the biomarkers do not distinguish between different food sources of dairy fat (e.g., cheese, yogurt, milk), and residual confounding by unmeasured or imprecisely measured confounders may exist.ConclusionsIn a large meta-analysis that pooled the findings from 16 prospective cohort studies, higher levels of 15:0, 17:0, and t16:1n-7 were associated with a lower risk of T2D.

Engineered butyrate-producing bacteria prevents high fat diet-induced obesity in mice

“…of obesity [11][12][13][14]. In recent years, researchers have shown that, as metabolites of gut microbiota, short-chain fatty acids (SCFAs) affect the physiological processes of disease by affecting energy supply and immune regulation [15], especially butyric acid (BA), which can alleviate obesity and insulin resistance in mice fed a high-fat diet (HFD) [16].…”

Development of a Liquid Chromatography–High Resolution Mass Spectrometry Method for the Determination of Free Fatty Acids in Milk

“…As discussed in the introduction, it is becoming clear that each particular FA may play a different role in human health [6,[16][17][18]. In the case of saturated FAs, odd-chain saturated C15:0 and C17:0 have shown to be associated with a lower risk of type 2 diabetes [18]. The levels of odd-chain FFAs C15:0 and C17:0 were estimated and found to be 0.5 ± 0.2 µg/mL and 0.6 ± 0.1 µg/mL in cow milk, respectively and 0.3 ± 0.0 µg/mL and 0.2 ± 0.0 µg/mL in goat milk, respectively.…”

“…It has been demonstrated that the high circulating odd-chain saturated fatty acid C17:0 is inversely associated with CVD and stroke mortality and potentially associated with higher risk of non-CVD death [17]. A recent large meta-analysis, which pooled the findings from 16 prospective cohort studies, has shown that higher levels of odd-chain saturated fatty acids C15:0 and C17:0 are associated with a lower risk of type 2 diabetes (T2D) [18].…”

Milk in the prevention and management of type 2 diabetes: The potential role of milk proteins

“…A prospective study among 2907 American adults aged 65 years or older suggested that long‐term exposure to pentadecanoic, heptadecanoic, and trans‐palmitoleic acids are not associated with increased risks of CVD incidence and mortality. Furthermore, a meta‐analysis of 16 prospective cohorts with a total of 63 682 participants showed that higher levels of pentadecanoic, heptadecanoic, and trans‐palmitoleic acids were associated with a lower risk of T2DM. The mechanisms underlying the inverse association between dairy product consumption and T2DM risk remain to be elucidated.…”