From Dry Mouth to Dizziness
Dehydration happens when your body loses more water than it takes in. Water is essential for nearly every bodily function: regulating temperature, carrying nutrients, cushioning joints and keeping organs working properly. Even mild dehydration can impact how you feel and function. While it’s easy to forget to drink enough water—especially when you’re busy, sick or active—knowing the early warning signs of dehydration can help you correct the problem before it becomes serious.
5 Signs of Dehydration
1. Persistent Thirst
Thirst is the body’s most obvious way of asking for water. If you feel thirsty often, or if the sensation is strong and doesn’t go away quickly, it’s a clear sign your body is already running low on fluids.
However, thirst isn’t always an early warning sign. By the time you feel it, dehydration may already be underway. Some people, including older adults, may not feel thirst as strongly, which makes it even more important to watch for other symptoms.
2. Dark Urine or Infrequent Urination
Your urine can tell you a lot about your hydration levels. When you’re well-hydrated, urine is usually pale yellow or almost clear. When you’re dehydrated, it becomes much darker, often a deep yellow, amber or even honey-colored.
You may also notice that you’re going to the bathroom less frequently than usual. In some cases, urine may have a stronger smell, which is another sign that water levels are low and waste products are more concentrated.
3. Fatigue and Low Energy
Dehydration can make you feel unusually tired, sluggish or mentally foggy. That’s because your body needs water to regulate blood pressure, circulate oxygen and keep muscles and organs functioning efficiently. Without enough fluids, the heart must work harder to push blood through your body, which can leave you feeling weak or drained.
Sometimes people mistake dehydration-related fatigue for lack of sleep or stress, so it’s helpful to think back about how much water you’ve had throughout the day.
4. Dry Mouth, Skin or Eyes
When your body lacks water, it prioritizes essential internal functions first. That means areas like the mouth, lips, skin and eyes may dry out. You may notice:
- A sticky or dry feeling in your mouth.
- Cracked lips.
- Itchy, irritated eyes.
- Skin that feels rough, flaky or less elastic than normal.
Severe dehydration can reduce sweating, which may make your skin feel unusually hot or dry even in warm weather.
5. Headaches or Dizziness
Headaches are a common early sign of dehydration. When there isn’t enough fluid in the body, the brain can temporarily shrink slightly from fluid loss, pulling away from the skull and causing pain.
Dizziness or lightheadedness can happen because dehydration lowers blood volume, making it harder for the heart to pump blood to the brain. This symptom is especially noticeable when standing up quickly.
If dizziness is significant or accompanied by confusion, it may signal more severe dehydration and should be treated right away.
How to Improve Your Water Intake and Stay Hydrated
Staying hydrated is simplest when you build small, steady habits. Drink water throughout the day rather than waiting until you’re thirsty, and keep a bottle nearby as a reminder. Eating water-rich foods such as oranges, watermelon, cucumbers and tomatoes also adds to your daily fluid intake. If you don’t enjoy plain water, try flavoring it with lemon, berries or mint, or choose sparkling water for variety.
Electrolytes can also play an important role. These minerals help balance fluids, support muscles and maintain proper nerve function. During heavy sweating, intense exercise, hot weather or illness, you lose electrolytes more quickly, and drinking an electrolyte beverage can help replace what your body has lost. For normal daily activities, though, water is usually enough.
Pay extra attention to hydration when you’re sick, active or in a warm environment, and notice the signals your body gives you. Signs like dark urine, headaches, fatigue or muscle cramps are reminders to increase your fluid intake. Sip water regularly rather than drinking large amounts all at once so your body absorbs it more effectively.
It's important to be able to spot the signs of dehydration, but taking care of your body and water intake so you avoid dehydration is even better.