Which of the following is a common sign of dehydration?

• A. Thirst
• B. Hair Growth
• C. Increased Appetite
• D. Cold Intolerance

Answer: (A)

Thirst is a primary signal the body uses to correct fluid loss. When you become dehydrated, your blood becomes more concentrated (higher osmolality), and sensors in the hypothalamus detect this change. That detection triggers the sensation of thirst, prompting you to drink and restore the fluid balance. This makes thirst a common, early sign of dehydration, helping you rehydrate before more serious symptoms develop.

The other options don’t fit dehydration. Hair growth isn’t tied to short-term fluid status, increased appetite isn’t a typical dehydration signal, and cold intolerance points more to temperature regulation or thyroid issues rather than fluid balance.