Think about it. Your brain is always “ON” means it has many things to think and worry about. It takes care of your thoughts and movements, your breathing and heartbeat, your senses — it works hard and continuous 24/7, even while you’re asleep. This means your brain needs a constant supply of fuel. That “fuel” comes from the foods you eat on daily bases — and what’s in that fuel makes all the changes. In simple terms, what you eat directly affects the structure and function of your brain and, eventually, your mood.