A sugar metabolism-improving agent containing at least one of a compound having a structure expressed by the following Structural Formula (1) and a compound having a structure expressed by the following Structural Formula (2) and having an effect of suppressing an increase in the postprandial blood sugar level, an effect of decreasing the fasting blood sugar level, an effect of controlling sugar metabolism-related indices in serum, an effect of promoting intake of sugar into muscle cells, and an effect of promoting metabolism of sugar derived from a meal a sugar metabolism-improving composition, an agent for suppressing an increase in the postprandial blood sugar level, an agent for decreasing the fasting blood sugar level, an agent for promoting intake of sugar, and food and drink each containing the sugar metabolism-improving agent.
