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Tea and coffee as sources of some minerals in the New Zealand diet
Abstract:
Daily intakes of tea and coffee of a representative sample of adult New Zealanders (865 men and 1100 women) were calculated from 24-h dietary recalls. The mineral concentrations in tea and coffee samples were determined by atomic absorption spectrometry and used to estimate daily mineral intakes from these beverages. More than 80% consumed tea and about 60% consumed coffee on the day of the recall. The men drank significantly more tea than the women (p less than 0.001), but coffee intakes were similar. The results indicate that for New Zealand adults tea is a very good source of manganese and it also contains appreciable amounts of potassium. Coffee is a better source of potassium than tea, has appreciable amounts of magnesium, and may contribute significantly to manganese intakes in some instances. The amounts of copper, zinc, sodium, calcium, and iron extracted from tea leaves and coffee beans in the brewing processes are too low to be of any nutritional significance but minerals in the water used in their preparation may make a significant contribution to dietary intakes.
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