An object of the present invention is to provide an active ingredient that can remarkably exhibit an effect of preventing and/or relieving osteoporosis or an effect of promoting bone formation and is usable as a food or drink product. The present invention provides an agent for preventing and/or relieving osteoporosis comprising component (A): an ascorbic acid derivative as an active ingredient, a composition comprising the agent, an composition for oral administration comprising component (A) and component (B): an extract from a plant in the family Piperaceae as active ingredients, a composition for promoting bone formation containing component (A) and component (D): sorbitol and/or a derivative thereof as active ingredients, and a composition, such as a pharmaceutical product, a quasi-pharmaceutical product, and a food or drink product, comprising any of these compositions.
