What the Mouth and Teeth Do. The first step of digestion involves the mouth and teeth. Food enters the mouth and is immediately broken down into smaller pieces by our teeth. Each type of tooth serves a different function in the chewing process. Incisors cut foods when you bite into them. The sharper and longer canines tear food.
CFS is most common in women ages 30 to 50. The hallmark symptom is persistent and profound fatigue, which often worsens after physical or mental exertion. Symptoms may also include muscle aches, headache, and extreme fatigue. The main symptom of CFS is extreme tiredness that is: New.
Causes of Similar Symptoms to Extreme fatigue. Research the causes of these symptoms that are similar to, or related to, the symptom Extreme fatigue: 1  Fatigue (3235 causes). 2  Chronic fatigue syndrome (3 causes). 3  Muscle weakness (4300 causes). 4  Tiredness (669 causes).