Carbohydrates have the job of providing all the cells in the body with the energy they need. When carbohydrates are consumed, the body turns them into glucose, which provides sufficient energy for everyday tasks and physical activity. The body needs a certain amount of carbohydrates to function properly, and an insufficient supply can cause such things as fatigue, muscle cramps, and poor mental function. A low-carb diet might seem healthy, but if taken to the extreme, can be very dangerous to a person's overall well-being. Therefore, be sure to eat moderate amounts of carbohydrates to keep your body fueled properly.