Yeah, you can lose belly fat just by walking. You can lose belly fat by doing any type of exercise/physical activity. Based on science, here’s how weight loss really works in the human body. Energy balance is the balance of energy you consume (calories you eat) versus the amount of calories you expend (through daily activity). If you consume fewer calories than you need to maintain your daily activities, then you’ll lose weight. If you consume more calories than you need to maintain your daily activities, then you’ll gain weight. Any exercise or physical activity causes you to burn extra calories, which will make the amount of calories burned greater, putting you at a greater caloric deficit. If all other things are in order, you’ll cut that belly fat.