2. Although tremella decoction contains many nutrients, it can play the role of beauty and hairdressing, as well as moistening intestines and relieving cough. But overnight tremella soup may reduce nutrition, easily produce some bacteria, and may lead to microbial infection. If you eat the tremella soup overnight, it will not only fail to play a health care role, but may also cause harm to your body. So it's best to eat fresh tremella soup to avoid eating too much at once.