The brain sends the same signal whether you are hungry or thirsty. To understand which signal your brain is sending, you must learn to understand your body better. Pay close attention to the last time you had a meal compared with the last time you had something to drink. It might be that empty feeling in your stomach only needs some water to be sated.
Source: Difference Between Being Hungry and Thirsty @ LiveStrong.com
Image: Water Impact 0 by (Henningklevjer) - (Henningklevjer). Licensed under CC BY-SA 2.5 via Wikimedia Commons.
