Submitted to: Journal of Nutrition
Publication Type: Peer reviewed journal
Publication Acceptance Date: 3/17/2010
Publication Date: 6/1/2010
Citation: Milbury, P.E., Vita, J.A., Blumberg, J.B. 2010. Anthocyanins are bioavailable in humans following an acute dose of cranberry juice. Journal of Nutrition. 140(6):1099-1104. Interpretive Summary: Research suggests that the plant chemicals called anthocyanins from berry fruit may be health beneficial and protect against cardiovascular disease by influencing the function of the endothelial cells lining the walls of blood vessels. However; little is known about how well these chemicals are absorbed into, metabolized in, and removed from the human body. A study was conducted in 15 patients (age: 62±8 y) with coronary artery disease to measure the absorption and removal of anthocyanins that are found in cranberries. Subjects drank 480 mL of a double strength cranberry juice and blood and urine were collected before and during a period up to 4 h after they drank the juice. The subjects showed marked differences in how well they could absorb and excrete anthocyanins but all subjects displayed the highest level of anthocyanins in their blood between 1–3 hours after drinking cranberry juice. The pattern of anthocyanins measured in plasma and urine was similar to the pattern seen in the juice. Plasma concentrations of the individual anthocyanins were low compared to other flavonoids such as tea catechins. The anthocyanins recovered in urine represented only 0.0116% of the anthocyanins contained in the juice. These data are in agreement with the other studies of anthocyanins from other foods suggesting that cranberry anthocyanins are poorly absorbed and rapidly removed from plasma. These data suggest that there are not enough anthocyanins in the body after drinking cranberry juice for them to exert health benefits by acting as antioxidants and quenching radicals. However; there are enough anthocyanins alter cell signaling and/or gene expression in ways that have health benefits.
Technical Abstract: Research suggests that anthocyanins from berry fruit may affect a variety of physiological responses, including endothelial function, but little information is available regarding the pharmacokinetics of these flavonoids in humans. To determine the pharmacokinetics of cranberry anthocyanins a study was undertaken in 15 patients (age: 62±8 y) with coronary artery disease. Blood and urine were collected between baseline (0 h) and 4 h after consumption of 480 mL cranberry juice (54% juice; 835 mg total polyphenols; 94.47mg anthocyanins). Marked inter-individual differences in plasma anthocyanin pharmacokinetics were observed with maximum anthocyanin concentrations detected between 1–3 h. Cranberry anthocyanins were bioavailable but with significant differences in the maximum concentration (Cmax) and area under the curve AUC0-4h between individual subjects. The pattern of anthocyanin glucosides observed in plasma and urine generally reflected the relative concentration determined in the juice. Plasma concentrations of the individual anthocyanins ranged between 0.56-4.64 nmol/L. Total urinary anthocyanin recovery was 0.0116% of the dose delivered. These data are in agreement with the pharmacokinetics of anthocyanins from other foods suggesting that cranberry anthocyanins are poorly absorbed and rapidly removed from plasma. Observed levels, while unlikely to significantly alter in vivo radical loads or redox potential, are sufficient to affect signal transduction and/or gene expression.