The best time of the day for adults to take probiotics is during or after meals. Probiotics are a kind of microbial flora that are beneficial to human health, mainly exist in the human intestine, and have the functions of maintaining the ecological balance of intestinal microorganisms, helping digestion, improving the immunity of the body, protecting the intestinal mucosa and improving the antioxidant capacity of the body. It is mainly used for the diseases of indigestion, diarrhea and constipation caused by the weakened intestinal function of children and the elderly. In addition, for the intestinal acute and chronic inflammation caused by the increase in the number of stools also has a good effect; and congenital lack of lactase people, due to the lack of sugar enzyme or lactose can not be broken down will appear bloating, diarrhea, appropriate supplementation probiotics have a good effect on the disease. However, probiotics can easily lose their effect under high temperature and acidic environment. The acidic environment in the stomach before meals can destroy the activity of probiotics, so it is best to take it during or after meals. In addition, probiotics should not be taken too much, scientific and reasonable use of probiotics can really benefit the human micro-ecological balance, beneficial to human health and immune function enhancement.