What are the symptoms of dehydration?

What the signs of Dehydration ?

 

Dr Jaroslav Boublik

 

In the fourth of this series of articles we will look at dehydration and understand how we can use symptoms of acute and chronic dehydration to help calibrate our fluid intake.

 

What is dehydration?

 

Dehydration is a metabolic state where a less-than-optimal level of fluid is available to facilitate normal biochemical and physiological processes.  When the volume fraction of fluid in the body rapidly drops below the normal level, even by just a few percent, the state is known as acute dehydration and it is a very serious condition requiring immediate attention via rehydration techniques.  Because of the fundamental nature of the body’s requirement for water, and the range of compensatory mechanisms available to address initial stage hypohydration, the symptoms may be vague until past the point when bringing the system back into balance is simply a matter of consuming more fluid. 

 

Less immediately dangerous, and much more common, is long-term, chronic dehydration where the volume fraction of fluid in the body is consistently a small fraction below ideal.  In this situation the set point for many physiological processes adapt, including the behaviors that drive us to seek and ingest hydrating fluid, resulting in a new set point, below the ideal.  When this happens it is much more difficult to move hydration back to the optimal level. 

 

The most dangerous situation is where someone who is chronically dehydrated becomes additionally acutely dehydrated because the systems that depend on optimal hydration, already pushed, are quickly overwhelmed and a very serious state of unwellness rapidly develops.

 

The reason dehydration is such a difficult issue to manage is that the symptoms are not particularly obvious until the level of dehydration is quite extreme especially in someone who has been chronically dehydrated for a long period of time.  In these people the acuity of their thirst reflex – the urge to seek and ingest water when fluid levels drop below the set point – has been compromised and they simply can’t feel that they need to drink.

 

The Signs and Symptoms of Dehydration

 

The first symptom of dehydration should be thirst but as we have noted above this response is often blunted.  Symptoms generally progress to more dire manifestations as the need for water becomes more extreme.   Someone who is chronically dehydrated at a point somewhere between normal and the mild dehydration we discuss below may even be able to develop a tolerance for that state so that it becomes the “new normal” for them.  Suffice to say that any level of dehydration can and will lead to long term consequences if left unaddressed.

 

The initial signs and symptoms of mild dehydration in adults appear when the body is depleted by about 2% of total fluid. In this mild dehydration state symptoms are:

 

•         Thirst (with caveats as above)

•         Reduced Appetite (often despite a lengthy period without food)

•         Skin Flushing (especially face and neck)

•         Dark Colored Urine (may be confused by supplement use or some foods)

•         Dry Mouth (and difficulty producing saliva)

•         Fatigue

•         Mild headache

•         Chills

•         Dizziness

 

At this point simple consumption of hydrating fluid will generally arrest any further development of symptoms.

 

If the dehydration is allowed to continue to develop so that fluid loss reaches 5% of total fluid the following symptoms of significant dehydration are evidenced:

 

•                Decreased sweating and urination

•                Increased heart rate, respiration and body temperature

•                Extreme fatigue

•                Muscle cramps

•                Severe headaches

•                Nausea and constipation

•                Neurosensory disturbances (tingling, numbness)

 

At this point simple consumption of significant amounts of hydrating fluid may arrest any further development of symptoms but often medical care and intravenous fluid are required.

 

When 10% of body fluid is lost immediate emergency help is required and in many cases this level of fluid loss is fatal. The symptoms of severe dehydration include:

 

•                Muscle spasms

•                Vomiting

•                Rapid pulse

•                Dim vision or temporary blindness

•                Painful urination with very low urine volume

•                Confusion

•                Respiratory depression

•                Neuromuscular seizures

•                Chest pain

•                Unconsciousness

 

Without immediate medical care including intravenous fluid, and other strategies to minimize organ damage, fatality or significant loss of organ function is almost certain.

 

The simplest way to address the issue of dehydration is to make sure you take steps to maintain an optimal level of hydration at all times and never allow these signs and symptoms to enter into your experience.

 

Cultivating an accurate thirst reflex, regular consumption of hydrating fluids, especially when exercise or environmental factors deplete body fluid levels, together with an awareness of the subtle signs of early stage dehydration should allow you to manage this important issue.

 

Bio:

 

Dr Jaroslav Boublik B.Sc.(Hons), Ph.D. (Med), MRACI, C.Chem. AACNEM

Jaroslav has spent almost 30 years in medical research with 15 years in drug development and then 15 years in nutritional medicine.  He consults to the nutrition industry as a formulator, researcher, presenter and educator.  His primary research interest is water and hydration and he is the co-developer of The Aqua Formulas.