Why You Should Drink More Water During Hot Weather

You need to dink more water when you're in hot weather.
Drink plenty of water when you're working in the heat. Jupiter Images/Getty Images

When you spend time outside in hot weather you probably start to feel thirsty in a fairly short time. That's a normal response and one you should pay close attention to — it means your body needs more water to deal with the heat.

Your body functions best within a certain temperature range, and when you get too warm, it needs to cool off. There are a couple of ways your body accomplishes this cooldown.

First, your blood vessels dilate to increase blood flow to the skin. This allows excess heat to radiate away from your body. Then you also start to sweat. Evaporation of the sweat cools the skin, which in turn helps to cool the whole body. But, the problem is that excessive sweating can lead to dehydration.

You sweat more when the temperature's hot, especially if you're working or exercising in the heat. Drinking water helps replenish the fluids lost by excessive sweating. If you don't get enough water, you may become dehydrated, and the combination of hot temperatures and dehydration can lead to serious heat-related illnesses.

Signs You Need More Water

Even before you become dehydrated, you'll feel thirsty, and your mouth may feel dry or sticky. After a while, you may also become lethargic and fuzzy-headed. Other signs include reduced urine output (and the urine is dark yellow). You might even notice your eyes look a bit sunken and feel dry.

Even a little dehydration can be a problem so don't ignore those early signs. Studies indicate subclinical (mild) dehydration reduces the cognitive ability and physical coordination.

Tips for Hydrating in Hot Weather

  • Start hydrating right away. It's easier to maintain your fluid balance if you start out in a well-hydrated state.
  • Schedule regular beverage breaks and keep a water bottle handy so you can take frequent sips of water while you work or exercise.
  • Choose electrolyte-replacing drinks for maximum water absorption.
  • Drink water after you've finished work or an exercise session.
  • Snack on fresh fruits like berries, watermelon, peaches, and nectarines.
  • Don't drink large amounts of plain water all at once — this can lead to hyponatremia or water-toxicity.

How do you know if you've consumed enough water? One way to gauge your hydration level is to look at the color of your urine. If you're well-hydrated, it should be pale. Also, you'll be urinating more frequently. 


United States National Library of Medicine MedLine Plus. "Dehydration." https://medlineplus.gov/dehydration.html.

The Annals of Occupational Hygiene. "Hydration, Hydration, Hydration." http://annhyg.oxfordjournals.org/content/54/2/134.long