When bacteria invades the urinary tract due to poor hygiene or after sex, it can lead to infection in the urinary tract. UTI is most common in women and it causes them to feel constantly tired whether it is a case of chronic or recurrent infection. If UTI is left undiagnosed it can lead to severe case of lethargy. Some of the symptoms of UTI are high fever, backache and constant fatigue. A doctor must be consulted in case you come across such symptoms.

People with underlying heart problems also get fatigued easily just by climbing stairs or even doing some light work. Consult a doctor if you feel that you might be having some heart ailment. By correcting the underlying heart ailment, the fatigue level will also drop.

Caffeine causes a short spurt of energy as it is a stimulant but it is very draining if too much is consumed. Overloading the body with caffeine will cause fatigue. Cutting down on the intake of caffeine will interfere less with proper sleep required by the body.

Dehydration is caused when the body is void of regular fluid intake. The body needs to be kept hydrated at all times to prevent extreme dehydration, which is another prime factor leading to fatigue.

Food fuels the bodily energies but some people develop food intolerance and allergies which can lead to tiredness. If the kind of food causing allergic reaction is left undetected, the person may suffer from extreme fatigue. The body releases cortisone and adrenaline into the blood stream to fight off allergic reactions but continuous intake of the offending food item will deplete the regular production in the adrenal gland for cortisone and adrenaline. This will result in energy drain which causes fatigue. Detecting and removing the undesirable food source is important.

Fatigue in some cases is caused due to blood sugar imbalance and may be accompanied by diabetes symptoms as well. This can cause a lot of fatigue and a doctor must be consulted as he can best ascertain whether the person is diabetic or not. In the case of diabetes, the doctor can bring it under control with medications. Once the diabetes is under control, the symptoms of fatigue are also curtailed.

This is an endocrine disorder which makes the thyroid glands produce less thyroid hormones and causes the person to feel drained and tired. Women suffer from under active thyroid glands more than men in the case of hypothyroidism. People with this problem have disturbed sleep as hypothyroidism causes the heart to beat faster, increased blood pressure, bouts of dysentery and bodily tremors. This can put excessive pressure on the body which in turn leads to excessive fatigue.

Anemia related fatigue is common among women, who have a heavy menstrual cycle or who have just delivered a baby. Most women suffer from mild to severe anemia during their reproductive years and this is one of the major cause of fatigue during which they may feel completely drained out. There are people with deficiency of iron folic, vitamin B12 and even kidney problems. All this contributes towards anemia which in turn causes fatigue. However, with enough iron intake, anemia disappears along with the fatigue in most cases.

Sleep apnea is a cause of sleep disturbance, where a person is unable to get complete rest as they keep waking up at night. This stops an individual’s breathing temporarily at night thereby suddenly waking them up with a jerk. This happens because the throat muscles temporarily collapse for about 10 to 30 seconds making it impossible for people to breath. They wake up with a jerk and gasping for air. If they do manage to fall asleep again, the same pattern follows and they wake up again. The brain thus does not get the required sleep.