Tea drinking has been associated with many health benefit claims, such as the prevention of dental caries and maintenance of normal blood glucose concentration. A plausible mechanism for these claims is the retardation of starch digestion by starch hydrolase inhibitors present in tea. In vitro experiments have shown that black tea contains more potent inhibitors than green and oolong tea for inhibiting salivary α-amylase. Thus, drinking tea may reduce the availability of fermentable sugar needed by oral bacteria, thereby reducing the risk of dental caries. Theaflavin-3-gallate, the characteristic polyphenolic compound in black tea, was shown to be the most potent competitive inhibitor of glycosidase amongst theaflavins. However, the amount of theaflavins present in common black tea could not account for its total inhibitory activity, instead, the collective action of black tea components might be responsible for reducing starch hydrolytic rates. The starch hydrolytic rates of black tea were moderate in comparison to acarbose and therefore have implications for reducing the severity of side effects. The hypothesized benefit of drinking black tea as a means of maintaining healthy blood glucose concentration requires human clinical trials to solidify the evidence.