Addition of milk does not affect the absorption of flavonols from tea in man

Tea is a major source of flavonols, a subclass of antioxidant flavonoids pr esent in plant foods which potentially are beneficial to human health. Milk added to tea, a frequent habit in the United Kingdom, could inhibit absorp tion of tea flavonoids, because proteins can bind flavonoids effectively. E ighteen healthy volunteers each consumed two out of four supplements during three days: black tea, black tea with milk, green tea and water. A cup of the supplement was consumed every 2 hours each day for a total of 8 cups a day. The supplements provided about 100 mu mol quercetin glycosides and abo ut 60 - 70 mu mol kaempferoi glycosides. Addition of milk to black tea (15 mi milk to 135 mi tea) did not change the area under the curve of the plasm a concentration-time curve of quercetin or kaempferol. Plasma concentration s reached were about 50 nM quercetin and 30 - 45 nM kaempferol. We conclude that flavonols are absorbed from tea and that their bioavailability is not affected by addition of milk.