Picture this: You're enjoying a bright, hot and sunny day. You've been outside for several hours, running around and enjoying the weather. All of a sudden, you start to feel lightheaded. You realize it's been a while since you last drank water.

No matter if you're spending time outside or staying indoors, it is always important to stay hydrated. Our bodies need water to function properly. After all, over 50% of the human body is composed of water.

If you're not drinking enough water, you may become dehydrated. Dehydration can lead to a series of symptoms, so it is key to recognize each to receive proper care. Here's what you need to know about dehydration.

What causes dehydration?

Dehydration is caused by a lack of sufficient fluids (primarily water) in the body. When you are losing or using more fluids than you are taking in, you become dehydrated.

The human body loses fluids in several ways, such as sweating, breathing, urination and defecation, as well as through tears and saliva. If you are not actively and sufficiently replacing those lost fluids, dehydration will occur.

While not drinking enough liquids is one cause for dehydration, it can be triggered by other health conditions, such as diarrhea, vomiting or excessive sweating.

Anyone can become dehydrated. Those at higher risk, however, are infants, children and older people. Infants cannot and children often do not communicate when they are thirsty, making them more prone to dehydration. The same goes for older people, especially those who have cognitive issues.

Dehydration can also be worsened by pre-existing conditions that lead to loss of fluids, such as diabetes causing frequent urination.

Can dehydration cause nausea?

Nausea can accompany dehydration. However, the nausea is not directly related to dehydration and usually occurs due to other symptoms.

For example, dehydration may cause dizziness, and dizziness can lead to nausea. People who are dehydrated often experience lower blood pressure or blood volume, causing dizziness. When this occurs, your blood is not flowing properly and may not be reaching your brain the way it should. As a result, dizziness can trigger loss of balance, lightheadness and/or wooziness. These additional symptoms can prompt nausea due to unpleasant movement sensations.

Another example is vomiting. Vomiting and dehydration often appear together. When you are vomiting, you are rapidly losing water and electrolytes, which leads to dehydration. If you are emptying your stomach, this may also trigger uneasiness known as nausea.

Dehydration symptoms

Dehydration symptoms vary depending on someone's age, according to the Cleveland Clinic and Mayo Clinic.

In adults, dehydration symptoms can include:

• Extreme thirst
• Less frequent urination
• Dark-colored urine
• Fatigue
• Chills
• Constipation
• Dizziness
• Red (flushed) skin
• Loss of appetite
• Muscle cramps
• Confusion, headache

In infants or children, dehydration symptoms can include:

• Dry tongue, mouth and lips
• No tears when crying
• Sunken eyes, cheeks
• Sunken soft spot on top of infant's head
• Irritability
• Less frequent urination
• Dry skin

If you or someone experiences any of the symptoms for a prolonged period, seek medical attention.

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