Black jujube has strengthen the effect of blood tonic. Black jujube is rich in vitamins, has a very strong role in strengthening the body's immunity, and pancreatic cancer, lung cancer, vomiting blood has obvious efficacy So far, I have not heard of its side effects. Of course, as long as you don't eat too much at one time, moderate and there will be no side effects. In addition, black dates and red dates combined into one to eat is a good product to protect the liver.