A food product containing an effective amount of an active agent which is hydroxymatairesinol, a geometric isomer or stereoisomer thereof, or an acceptable salt thereof, or a mixture thereof, where the food product is selected from the group consisting of a nutritional supplement and a nutrient. The food product can increase the level of enterolactone or another metabolite of hydroxymatairesinol in a person's serum thereby causing prevention of a cancer or a certain non-cancer, hormone dependent disease in a person, based on the administration of hydroxymatairesinol to the person.