The sensation of being cold or experiencing chills can be a direct result of dehydration. This feeling is often unexpected because dehydration is usually associated with heat, but it is a genuine response by the body attempting to manage insufficient fluid levels. Dehydration occurs when the body loses more fluid than it takes in, preventing it from carrying out its normal functions. This state of low body fluid interferes with the processes responsible for maintaining a stable internal temperature, leading to a feeling of being chilled or developing shivers.
How Dehydration Disrupts Body Temperature
Water plays a primary role in maintaining the body’s core temperature by distributing heat. When the body becomes dehydrated, the total volume of blood decreases because blood is largely composed of water. This reduction in blood volume triggers a protective response aimed at maintaining blood pressure and ensuring blood continues to reach the most important organs.
The body attempts to conserve its diminished fluid supply by activating peripheral vasoconstriction. This process involves the narrowing of blood vessels, particularly those near the surface of the skin and in the extremities, such as the hands and feet. By constricting these vessels, the body redirects blood away from the skin and toward the core organs, prioritizing their function.
This internal diversion means less heat is transported to the skin, the body’s primary surface for heat exchange. The resulting drop in skin temperature is interpreted by the nervous system as cold exposure. This prompts the temperature-regulating center to initiate shivering or chills, which are muscular contractions intended to generate heat internally. The chills are a secondary effect, representing the body’s compensatory effort to warm itself when its heat distribution system is compromised by low fluid volume.
Other Physical Signs of Dehydration
Beyond the feeling of coldness, a lack of sufficient body fluid triggers several other physical responses. One reliable indicator is a change in urine color, which becomes darker yellow or amber as the kidneys conserve water. The mouth and tongue may also feel unusually dry or sticky because the body reduces saliva production to retain moisture.
Feeling fatigued or experiencing dizziness are common signs that the body is struggling with low fluid levels. The reduced blood volume can lead to a drop in blood pressure, limiting oxygen and nutrient delivery to the brain and muscles. Muscle cramps, especially in the legs, frequently occur because dehydration disrupts the balance of electrolytes necessary for proper muscle function. These symptoms often develop alongside an increased feeling of thirst, the body’s direct signal that fluid intake is needed immediately.
Immediate Steps for Rehydration
For mild to moderate dehydration, the immediate focus should be on replacing lost fluids and electrolytes. Plain water is the most straightforward choice, but it is best paired with an oral rehydration solution (ORS) if fluid loss was due to intense sweating, vomiting, or diarrhea. An ORS contains a balanced mixture of sugar and salts that allows water to be absorbed more efficiently into the bloodstream.
Avoid highly concentrated sugary drinks like sodas or full-strength fruit juices, as their high sugar content can draw water into the digestive tract and potentially worsen the fluid imbalance. Drinks containing alcohol or high amounts of caffeine should also be avoided because they increase fluid loss through urination. If the chills persist, or if symptoms escalate to severe confusion, an inability to keep fluids down, or a rapid heart rate, seek professional medical attention immediately.