どうしてお腹がすくと「グー」と音が鳴るの？
Your stomach growls when you are hungry because your stomach and intestines are moving. Even when there is no food, they keep contracting to push food along. As they move, they also push air and liquid, causing vibrations and making noise. This sound is called "borborygmus," and it is a sign that your body wants more food!
