Consumption of black currants, lingonberries and bilberries increases serum quercetin concentrations.
OBJECTIVE
To study serum quercetin concentrations of subjects consuming berries or habitual Finnish diets.


METHODS
Randomized parallel dietary intervention.


METHODS
Forty healthy men (age 60 y).


METHODS
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=0.039 ANCOVA with repeated measures). During the berry consumption period the mean serum concentrations of quercetin ranged between 21.4 and 25.3 micro g/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+/-1.4 mg/day (mean+/-s.e.m.) in the berry group and 5.8+/-0.6 mg/day in the control group (P=0.001).


CONCLUSIONS
The results indicate that the berries used in this study are a good source of bioavailable quercetin.
Erlund
I
I
Biomarker Laboratory, National Public Health Institute, Helsinki, Finland. iris.erlund@ktl.fi
Marniemi
J
J
Hakala
P
P
Alfthan
G
G
Meririnne
E
E
Aro
A
A
D000704:Analysis of Variance; D001682:Biological Availability; D006801:Humans; D007408:Intestinal Absorption; D008297:Male; D008875:Middle Aged; D011794:Quercetin / Q000008:administration & dosage / Q000097:blood* / Q000493:pharmacokinetics; D031965:Ribes / Q000737:chemistry; D029800:Vaccinium myrtillus / Q000737:chemistry; D029801:Vaccinium vitis-idaea / Q000737:chemistry
D011794:Quercetin