Consumption of black currants, lingonberries and bilberries increases serum quercetin concentrations

Abstract

Objective: To study serum quercetin concentrations of subjects consuming berries or habitual Finnish diets. Design: Randomized parallel dietary intervention. Subjects: Forty healthy men (age 60 y). Intervention: Twenty subjects consumed 100 g=day of berries (black currants, lingonberries and bilberries) for 8 weeks. Twenty subjects consuming their habitual diets served as controls. Fasting blood samples were obtained 2 weeks prior to the study, at baseline, and at 2, 4 and 8 weeks. Intake of quercetin was assessed from 3 day food records collected at baseline and at 8 weeks.Results: The serum quercetin concentrations were significantly higher in the subjects consuming berries compared to the control group (P ¼ 0.039 ANCOVA with repeated measures). During the berry consumption period the mean serum concentrations of quercetin ranged between 21.4 and 25.3 mg=l in the berry group, which was 32 -51% higher compared with the control group. According to 3 day food records, there was no difference in quercetin intake at baseline, but at 8 weeks the intake was 12.3 AE 1.4 mg=day (mean AE s.e.m.) in the berry group and 5.8 AE 0.6 mg=day in the control group (P ¼ 0.001). Conclusions:The results indicate that the berries used in this study are a good source of bioavailable quercetin.

Physicochemical and Bioactive Characteristics of Wild Grown Bilberry (Vaccinium myrtillus L.) Genotypes from Northeastern Turkey

“…The total anthocyanin content of bilberry is generally in the range of 300-700 mg per 100 g fresh fruit, although this range varies with cultivar, growing conditions and degree of ripeness of the berry (Upton, 2001;Burdulis et al, 2009). Along with anthocyanins, 100 g of fresh bilberry contain small quantities of vitamin C (3 mg), quercetin (3 mg), and catechin (20 mg) (Upton, 2001;Erlund et al, 2003).…”

Berry meals and risk factors associated with metabolic syndrome

“…The aim of this study was to create a study design in which the only difference between groups would be the amount of berries in the diets and power estimation based on the results of Erlund et al (2003) aimed to assure the statistically different intake of berry constituents in the intervention groups. P-value of 0.05 was applied, which gave f(ab) ¼ 7.9 at 80% probability, and thus n ¼ (2s.d.…”

Predictors for Reporting of Dietary Assessment Methods in Food-based Randomized Controlled Trials over a Ten-year Period

“…The second assessment was more likely to be at the midpoint of the study (32.3%, n D 32) , Donaghue et al, 2000, Riddell et al, 2000, Smith-Warner et al, 2000, Davidson et al, 2001, McGavin et al, 2001, Leslie et al, 2002, Shah et al, 2002, Chee et al, 2003, Drummond et al, 2003, Hendriks et al, 2003, Moeller et al, 2003, Sondergaard et al, 2003, Mori et al, 2004, Dyerberg et al, 2004, He et al, 2004, Bhargava et al, 2004, Maskarinec et al, 2004a, Maskarinec et al, 2004b, Shah et al, 2004, Sloth et al, 2004, Tapsell et al, 2004, Waller et al, 2004, Hermansen et al, 2005, Barnard et al, 2006, Chen et al, 2006, Iyer et al, 2006, Marfella et al, 2006, Ashley et al, 2007, Murphy et al, 2007, TurnerMcGrievy et al, 2008, Barnard et al, 2009, Davis et al, 2009) with 25 studies completing their dietary assessments in only two periods of assessment of which only 11 included the endpoint of the study as the final time point. (Barr et al, 2000, Conceicao de Oliveira et al, 2003, Erlund et al, 2003, Griffin et al, 2006, Haub et al, 2005…”