Can black fungus and shiitake mushrooms be eaten together?
Under normal circumstances, wood ear fungus and shiitake mushrooms can be eaten together. Details are as follows:

From the perspective of food safety, both wood ear fungus and shiitake mushrooms are common edible fungi. There are no toxins or components in these two foods that would interact with each other, so consuming them together will not cause poisoning or other adverse reactions. Furthermore, from a nutritional standpoint, both wood ear fungus and shiitake mushrooms are rich in nutrients such as protein, cellulose, vitamins, and minerals. Combining them in the diet can enhance the nutritional profile and provide more comprehensive nutritional support for the body.
However, for individuals with weak digestive systems, those prone to diarrhea, or those with gastrointestinal discomfort, consuming large quantities of both wood ear fungus and shiitake mushrooms together may increase the burden on the gastrointestinal tract, potentially causing symptoms such as bloating and diarrhea. This is because both contain plant-based fiber. Some individuals may be allergic to either wood ear fungus or shiitake mushrooms, and in such cases, they should avoid consuming them together to prevent allergic reactions.
In daily diet, balanced intake of various foods and maintaining a reasonable dietary structure are key to maintaining health.