well, what kind of diet are you doing, if its a "im practically straving myself diet" then i would suggest eating healthier without over eating. If the diet your on cuts out a certain group of food, than thats what might be making you tired, make sure your diet includes ALL food groups ( except that candy sugar one ya?) your body needs food to run, the only reason why people are overweight is because we abuse the privilage to stay alive. get it? P.S. if this diet is pretty healthy and your still tired, try going to a doctor and she or a referred nutritionist can put you on a diet that is healthy and helpful at the same time. P.P.S my dad is the same way :P