Intakes of Anthocyanins and Flavones Are Associated with Biomarkers of Insulin Resistance and Inflammation in Women

Abstract

Although laboratory data suggest that several flavonoid subclasses are involved in glucose metabolism, limited clinical and epidemiologic data are available. The current study examined associations between habitual intake of flavonoid subclasses, insulin resistance, and related inflammatory biomarkers. In a cross-sectional study of 1997 females aged 18-76 y, intakes of total flavonoids and their subclasses (flavanones, anthocyanins, flavan-3-ols, polymeric flavonoids, flavonols, flavones) were calculated from food frequency questionnaires using an extended USDA database. Fasting serum glucose, insulin, high-sensitivity C-reactive protein (hs-CRP; n = 1432), plasminogen activator inhibitor-1 (n = 843), and adiponectin (n = 1452) concentrations were measured. In multivariable analyses, higher anthocyanin and flavone intake were associated with significantly lower peripheral insulin resistance [homeostasis model assessment of insulin resistance; quintile 5 (Q5) to Q1 = -0.1, P-trend = 0.04 for anthocyanins and flavones] as a result of a decrease in insulin concentrations (Q5-Q1 = -0.7 μU/mL, P-trend = 0.02 anthocyanins; Q5-Q1 = -0.5 μU/mL, P-trend = 0.02 flavones). Higher anthocyanin intake was also associated with lower hs-CRP concentrations (Q5-Q1 = -0.3 mg/L, P-trend = 0.04), whereas those in the highest quintile of flavone intake had improved adiponectin concentrations (Q5-Q1 = 0.7 μg/L, P-trend = 0.01). Anthocyanin-rich foods were also associated with lower insulin and inflammation levels. No significant associations were observed for total or other flavonoid subclasses. Higher intakes of both anthocyanins and flavones were associated with improvements in insulin resistance and hs-CRP. These associations were found with intakes readily achieved in the diet. The observed reduction in insulin concentrations was similar to that reported previously for other lifestyle factors. Dose-response trials are needed to ascertain optimal intakes for the potential reduction of type 2 diabetes risk.

Berry anthocyanin intake and cardiovascular health

“…Interestingly the greatest reduction in hypertension was observed in the younger/ middle-aged women, supportive evidence for the observed reduction in risk of MI in this age group Cassidy et al 2011). Higher habitual anthocyanin intakes (35mg, half a portion of berries), resulted in a 0.7 mIU/L reduction in insulin levels (Jennings et al 2014) similar to the effects of a low-fat diet (Shikany et al 2011) or 1hr/day walking (Fung et al 2000). The magnitude of associations are clinically relevant and of significant public health importance.…”

“…The available data on the effects on inflammatory biomarkers are equivocal (Table 2, (Chun et al 2008;Jennings et al 2014;Landberg et al 2011) although more recent work, using a combined inflammatory score suggests that reduced inflammation may be a key pathway ; recent prospective data also support the importance of weight maintenance . Interestingly the greatest reduction in hypertension was observed in the younger/ middle-aged women, supportive evidence for the observed reduction in risk of MI in this age group Cassidy et al 2011).…”

Association of Dietary Flavonoid Intake with Prevalence of Type 2 Diabetes Mellitus and Cardiovascular Disease Risk Factors in Korean Women Aged ≥30 Years

“…In particular, in our study the odds ratio for the risk of T2DM was lower in the subjects at or above the 25th percentile of flavone intake in comparison with those below the 25th percentile. Jennings et al (17) in a cross-sectional study, reported that higher flavone intake in women was associated with significantly lower insulin resistance (HOMA-IR) as a result of decreased insulin concentrations. Other studies have shown that flavones improve insulin resistance both in vitro (38) and in vivo (34).…”

“…Jennings et al (17) in a cross-sectional study found that higher intakes of flavones were associated with improvements in C-reactive protein, a biomarker of adiposityassociated inflammation. We also observed that dietary flavone intake was negatively associated with TG and TG/HDL-C ratios.…”

“…The consumption of dietary flavonoids has been shown to be associated with lower incidences of T2DM (7,8). Abundant literature exists reporting that flavonoids decrease plasma glucose and improve insulin secretion and insulin resistance (HOMA-IR), factors which are implicated in the development of T2DM (16,17). One of the main causes of morbidity and mortality observed among individuals with T2DM is CVD.…”