Many people prefer to go on a zero-carbohydrate diet to shed weight and look slim. While this might look an easy and affordable option for weight loss know it has its own perils. Lack of carbohydrate in your diet can make you dumb and your brain less active over time. Our brain functions solely on glucose which is the end product of carbohydrate metabolism. This is the reason why when the body goes into hypoglycaemia (low glucose state especially in diabetics) one goes in a coma as the brain ceases to function informs Soly James Chief Dietician Raheja Hospital Mumbai.