A composition that includes methylphosphinic acid or a salt thereof, and optionally methylphosphonic acid or a salt thereof, and an ingredient acceptable for consumption by a mammal is provided herein. Also provided is a method for reducing aging in a mammal that involves providing or administering methylphosphinic acid or a salt thereof, and optionally, methylphosphonic acid or a salt thereof, to the mammal in need thereof for consumption. A composition for use in such a method and an article useful for such a method include those in the form of a food product such as a prepackaged or processed food or meal, a beverage, a nutritional supplement, or a nutraceutical.