6. Muscle Cramps
Muscle cramps may be a sign of dehydration. Cramps are particularly common when dehydration is caused by excessive sweating.
Interestingly, sweating can result in a significant loss of both fluid and sodium, which is an electrolyte that plays a role in muscle contractions.
For this reason, adequate hydration is especially important during strenuous exercise or exercise in high temperatures.
Summary: Fluid and sodium depletions can lead to muscle cramps. Drinking water is particularly important during strenuous exercise.
7. Decrease in Blood Pressure
Low blood pressure can be a symptom of dehydration (22).
Interestingly, low blood pressure might make you feel light-headed or dizzy when you go from lying down to standing up (24).
That's because your heart has to pump faster and harder to get blood to the brain when there is less fluid in the body. When you stand up, it may take a few seconds for blood to get to the brain from the lower limbs.
What's more, low blood pressure can make you feel weak and tired.
Nevertheless, a small drop in blood pressure is relatively harmless and usually remedied by drinking water (25).
On the other hand, severe dehydration can lead to dangerously low blood pressure. Symptoms like blurred vision, nausea and fainting could indicate very low blood pressure that requires medical attention (24).
Summary: Dehydration can cause a drop in blood pressure, which might make you feel light-headed, weak and tired. Severe dehydration can cause dangerously low blood pressure that requires medical attention.
8. Rapid Heart Rate or Heart Palpitations
Dehydration can cause a rapid heart rate or heart palpitations. Palpitations give you the feeling that your heart is jumping or skipping a beat.
Interestingly, these abnormalities are a result of the heart attempting to compensate for the lack of fluid in the body.
When there's not enough fluid in your body, it decreases the volume of blood in your blood vessels. Your body then works hard to deliver enough blood to your organs by increasing its heart rate, pumping blood more quickly throughout your body (5, 26).
When this happens, you might feel your heart racing, fluttering or pounding extra hard.
Fortunately, in most cases of dehydration, this increase in heart rate effectively makes up for the low blood volume. Even with less blood pumping through the body, the organs and tissues are able to receive what they need.
However, as dehydration becomes more severe, the heart becomes less effective at compensating for the lack of fluid. If the heart is unable to get blood to the organs, they will eventually shut down.
Keep in mind that dehydration is not the only condition that affects heart rate. Rapid heart rate or palpitations can also indicate a more serious medical condition.
That being said, if your heart rate does not return to normal after drinking water, you should consult a medical professional.
Summary: A lack of fluid in the body decreases blood volume. The heart makes up for the lack of blood volume by working harder and faster to pump blood throughout the body.
9. Irritability or Confusion
Dehydration can have a significant effect on brain function.
Furthermore, brain function can deteriorate significantly as dehydration becomes more severe. Severe dehydration can cause confusion and incoherence (29).
In fact, confusion and even delirium are common symptoms among older adults who are dehydrated. Older adults are particularly susceptible to becoming dehydrated due to their sense of thirst declining with age (30, 31, 32).
Conversely, drinking plenty of water has a positive effect on mental clarity and brain function. In fact, both children and adults have been found to perform tasks better when they are well hydrated (33, 34, 35).
In one study, children who were given additional water to drink had improved short-term memory and performed better in school (33).
Overall, it appears that hydration status can have a significant impact on mental performance.
Summary: Dehydration can negatively affect brain function and cause symptoms like moodiness, anxiety, decreased concentration and confusion.
10. Serious Complications and Organ Failure
Severe dehydration can lead to very serious complications.
Every organ in the body requires fluid to function properly. If dehydration becomes critical, organs will begin to shut down.
In fact, a severe loss of body fluid can lead to shock, which is a potentially fatal condition (36).
Shock occurs when the volume of blood becomes so low that the brain and other organs are not able to receive the oxygen they need (37).
Moreover, shock can cause complications like loss of consciousness, brain damage, kidney failure and heart attack. If shock is not treated immediately, it will result in death (38).
That being said, shock is a rare consequence of dehydration that only occurs with an extreme loss of body water. It is most likely to come about when fluid is lost through trauma, severe burns or prolonged vomiting and diarrhea.
Summary: Extreme dehydration can cause shock and organ failure. This level of dehydration can be fatal if not treated immediately.
How to Prevent Dehydration
The key to preventing dehydration is to drink plenty of water throughout the day, along with other beverages like unsweetened coffee and tea.
Interestingly, water-rich foods like fruits and vegetables also contribute to hydration.
However, there's no magic amount of fluid you should drink every day to stay hydrated (39).
Fluid requirements vary from person to person and are affected by activity level, amount of sweat and climate (40).
Nevertheless, here are some tips to stay hydrated:
- Drink when you are thirsty: For most people, thirst is a reliable indicator that your body needs water. If you feel thirsty, drink water (1).
- Drink plenty of water before exercising: It's important to be properly hydrated before you start exercising, particularly if you are going to be active in the heat.
- Replace fluids lost through sweat: If you sweat a lot, you will need to drink extra water to replace lost fluids. In this case, you may need to drink more than your thirst demands (12).
- Keep tabs on the color of your urine: The color of your urine is a good indicator of your hydration status. Drink enough water so that your urine maintains a pale yellow color.
- Replace fluids lost through vomiting or diarrhea: Sip on liquids or ice chips if you are experiencing vomiting or diarrhea. If you are unable to keep fluids down for more than 24 hours, seek medical attention.
Summary: In order to prevent dehydration, drink when you are thirsty and replace fluids lost through sweat or illness.
The Bottom Line
Symptoms of dehydration range from thirst, in the case of mild dehydration, to organ failure when dehydration is severe.
While most cases of dehydration can be easily remedied by drinking water, more severe dehydration will likely require medical attention.
Drinking plenty of fluids can prevent dehydration and its side effects.
Furthermore, staying properly hydrated may have additional benefits, such as boosting your mood, fighting fatigue and improving memory and concentration.
Reposted with permission from our media associate Authority Nutrition.