When you have stress, your brain may need serotonin. Serotonin have an effect on prevent from stress. How can we get Serotonin? Tuna and Bonito (Katsuo) have ingredients such as tryptophan and Vitamin B6. Those make serotonin. Serotonin is a hormone. If you don’t have enough serotonin, your brain will make stress. Serotonin is fully contained in a bonito and a tuna. So you should eat them. It’s good for your sleep too. Serotonin help your sleep because serotonin can control your brain and body. It’s a good hormone. You won’t have stress and you can sleep well if you have enough serotonin in your body.