Not enough sleep. This can negatively affect your concentration and health. Adults should get seven to eight hours every night. Make sleep a priority and keep a regular schedule. Ban laptops, cell phones, and televisions from your bedroom.

Not eating enough. Not eating enough causes fatigue. So does eating unhealthy foods. Eating a balanced diet helps keep your blood sugar in a normal range and prevents you from feeling fatigued when your blood sugar drops. Make sure to always eat breakfast and try to include protein and complex carbs in every meal.

Hypothyroidism. The thyroid gland controls your metabolism. When the gland is underactive and the metabolism functions too slowly, you may feel slower than usual and put on weight. Get a blood test to check if your thyroid hormones are low. If so, consider taking synthetic hormones.

Depression. Depression can make you experience fatigue, headaches, and loss of appetite. See your doctor about therapy and possibly getting on anti-depressants.

Too much caffeine. While caffeine makes you feel alert, too much can increase heart rate, blood pressure, and anxiousness. Too much actually causes fatigue in some people. Try to slowly drink less coffee, tea, chocolate, soft drinks, and any medications that contain caffeine. Stopping suddenly can cause caffeine withdrawal and more fatigue.

Sleep apnea. This stops your breathing at night, which wakes up you up all night. This causes you to be sleep-deprived. Lose weight if you're overweight, quit smoking, and you may need a CPAP device to help keep your airway passages open while you sleep.

Anemia. Leading cause of fatigue in women. Menstrual blood loss can cause an iron deficiency, putting women at risk. Red blood cells are needed because they carry oxygen to your tissues and organs. If the anemia is caused by an iron deficiency, take iron supplements and eat iron-rich foods.