The interindividual variation of salivary flow rate and biochemistry in healthy adults: Influence of black tea consumption

Saliva is firstly interacted with food or drink during ingestion. Alteration of salivary biochemistry by black tea consumption is unclear and rarely discussed in literature. The current work highlighted the immediate and delayed effect of black tea drinking on the change of several salivary parameters, including flow rate, α-amylase and catalase activity, malondialdehyde, thiol, nitric oxide, hydrogen peroxide and total protein content. Twelve healthy subjects aged between 22 and 31 years old were recruited in the study. The saliva was collected before, after and 30 min after black tea consumption. The black tea intake generally caused an increase of salivary flow rate, total protein content, catalase, H2O2 and MDA but reduction in thiol and nitric oxide for majority of the subjects. Principal component analysis showed that the salivary flow rate, production rate of total protein content, nitric oxide, thiol and malondialdehyde of saliva were primarily significant for black tea consumption.