• Drinking water throughout the day can prevent moderate dehydration.fitness girl image by T.Tulic from Fotolia.com
  
  It's a common saying that the average human being should drink eight glasses of water each day in order to stay hydrated. In fact, according to the Mayo Clinic, the amount of water you drink depends on your health, exercise level and location. See resources for advice on how to calculate personal water intake levels. Too little water can cause moderate dehydration, the signs of which are many. A moderately dehydrated human should drink water to get his hydration level back up.
  
  

Dry Mouth

• Moderate dehydration will cause a dry mouth. Sometimes a dry mouth will feel sticky, which is also a symptom of moderate dehydration. Thirst can also accompany a dry mouth caused by dehydration.
  
  

Sunken Eyes

• Sunken eyes can be a sign of moderate dehydration. In children, the fontanel (the soft spot on a child's head) is sunken.
  
  

Lethargy

• Moderate dehydration can cause sleepiness and lethargy. If you're feeling tired and have one or more symptoms, it is possible you are moderately dehydrated.
  
  

Headache

• A headache can be a sign of moderate dehydration, especially if it appears after exercise or a lack of water. Nausea can accompany a dehydration headache; therefore, drinking water throughout the day is the best way to avoid dehydration headaches and nausea.
  
  

Irritability

• Irritability can present in dehydrated adults and dehydrated children. Remind children to drink water to avoid sudden crankiness, especially in the afternoon, which can signal mild to moderate dehydration.
  
  

Dark Urine

• Urine is a good way of measuring dehydration levels. Pale or clear urine signifies a hydrated body, and dark yellow urine suggests dehydration. Check the color of your urine before flushing it to see if you need more water.
  
  

Lack of Tears

• If a moderately dehydrated person attempts to cry, little or no tears will come out. The more dehydrated the person, the less likely they will produce tears.
  
  

Weakness

• A general feeling of weakness, coupled with lethargy or any other symptoms can suggest moderate dehydration. A feeling of stiff joints can often accompany weakness caused by moderate dehydration.
  
  

Skin Doesn't Bounce Back

• If your skin does not bounce back immediately when you press on it, it is likely that you have moderate dehydration.