Leaves are used. Components are xanthines like caffeine (50 a 80 mg per cup of black tea, half this amount for green tea and less for white tea), theophylline, theobromine; tannins, flavonoids (quercetin) Attributed properties: Psycho-stimulant, vasoconstrictor, diuretic, bronchodilator. At latest update, relevant published data on excretion into breast milk were not found. Data on excretion in the milk is available since caffeine and quercetin were measured into the breast milk after consumption of tea. There is not scientific proof on its effectiveness as a galactagogue ( increment of milk production) nor any anti-oxidant property was found in the milk. The use of tea bags was not found to be more effective for nipple pain relief than other methods for local use (hot compresses, breast milk, creams) Because a high caffeine consumption as that of 4 to 5 cups of tea a day (> 300 mg of caffeine) may induce nervousness and irritability in the infant. It is recommended a minimal consumption of tea during pregnancy and breastfeeding since contamination with lead has frequently been found, as well as other toxins like cadmium, aluminum, magnesium and brominated substances (PBDE), along with liver failure after consumption of green tea with slimming purposes..