Glucides are indispensable for providing the body with energy. You may experience a general sense of discomfort if you deprive yourself of sugars, which often happens to persons who want to lose weight. Your organism, which is then forced to use up reserves of fat to synthesize its own glucose, is placed under a constant strain, resulting in various symptoms of discomfort and/or fatigue. A Vitamin C deficiency, which is quite common among smokers, can also cause general discomfort. To obtain more Vitamin C increase your intake of fresh fruit and vegetables.