Zinc is best absorbed when taken on an empty stomach or before a meal. Any nutrient is more easily absorbed when taken on an empty stomach between 7-9 am. In addition, before meals is the time when a person needs to take nutrients, and taking zinc at this time can rapidly activate the digestive enzymes in the body, thus achieving better absorption. However, some zinc supplements have certain side effects and need to be taken after meals. Therefore, for optimal absorption of zinc, it is recommended to choose zinc supplements that can be taken on an empty stomach or before meals, such as zinc protein, which does not precipitate zinc ions in the stomach and thus does not cause gastrointestinal irritation. In addition, the absorption of ions in the digestive tract can interfere with each other and reduce the absorption rate, so zinc should not be supplemented with iron or calcium at the same time. When zinc is supplemented with iron or calcium, it is best to take them at least 2-3 hours apart.