What is the Japanese diet and how can it help your gut health? A tradition Japanese diet consists of minimally processed, seasonal foods served in a variety of small dishes. Meals are usually made up of steamed rice, noodles, fish, tofu, natto, seaweed, and fresh, cooked, or pickled fruits and vegetables. Depending on the pickling process, some pickled foods are classified as fermented. There is growing evidence to suggest fermented foods are good for our gut health.