The benefits of eating an apple a day are as follows: 1. It can promote the secretion of digestive juices and improve the digestive function because apples are rich in organic acids such as malic acid, succinic acid and pyruvic acid, which can well stimulate the secretion of digestive juices in the digestive tract and have strong benefits for improving digestive function. 2. These dietary fibers can mechanically stimulate intestinal peristalsis and promote bowel movement, thus reducing the incidence of constipation and colorectal cancer.