It would be a bad idea to ignore it. If your body is telling you that it needs food or drink, you need the 'right' food to keep your body energized. When I exercise, I prefer to drink gatorade but its a personal thing, there are benefits to an energy drink over water.
Depending on your exercise intensity, having some food/ snack would be helpful. Personally, I like Tuna as it is packed full of protein and is low in calories. I find it fills me up for longer than having carbs.
For me the goal of losing weight has been to reduce my calorific intake (food) over the amount of output (exercise) I do. As long as my food intake is less than my exercise, I am happy and content.
Hope this helps