Farmworkers stand in line to get a drink of water from a cooler
Photo credit: Hector Amezcua, College of Agricultural and Environmental Sciences, UC Davis

Top 3 Ways to Stay Hydrated on a Hot Day

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When it’s hot outside, your body helps cool you down and maintain a healthy temperature by releasing water onto your skin (otherwise known as sweating). When the sweat evaporates from your skin, it takes a little bit of body heat with it.

Your body needs a certain amount of water for your organs to work properly. If you don’t replace the water that you are releasing as sweat, your body will not function well. When your body does not have enough water (known as dehydration), it is like forcing a car to work without enough coolant; it may break.

How to Stay Healthy and Hydrated on a Hot Day

#1 Drink one cup of water every 15 minutes.

Cal/OSHA recommends drinking one cup (8 ounces) of water every 15 minutes, or four cups (32 ounces, approximately one liter) over the course of an hour. How much is 8 ounces? About the size of your fist.

#2 Drink small amounts throughout the day, not all at once.

If you drink all four cups at once, your body will absorb what it can, but it won’t be able to use it all and you may have to go to the bathroom to get rid of the extra water. However, if you drink small amounts frequently over the course of each hour before you feel thirsty, your body will use the water that you drink as you sweat throughout the day.

#3 Water is the best!

Not all liquids keep us hydrated like water.

  • Sports Drinks:
    When you sweat for a long period of time, your body not only loses water, it also loses important minerals, called electrolytes, that help your body function. Sports drinks were created for athletes to help them replace the electrolytes they lose when sweating over long periods of time. However, in addition to water and minerals, sports drinks can also contain a lot of sugar. Drinking sports drinks instead of water can contribute to health issues like type 2 diabetes. Sports drinks should not completely replace water, but if you are sweating a lot, you can substitute one cup of water with one cup of sports drink up to twice a day.
  • Soda:
    Similar to sports drinks, sodas contain a lot of sugar and can contribute to health issues like type 2 diabetes. Sodas should not be used for hydration.
  • Energy Drinks:
    Energy drinks contain chemicals, sugar, and stimulants, which can cause side effects like high blood pressure, rapid heartbeat, and insomnia. Some of the ingredients may provide a temporary boost and block the sensation of being tired, but they can cause serious health effects. Energy drinks should NEVER be used to hydrate your body.
  • Coffee:
    A cup of coffee may not be an issue, but you need to drink water to stay hydrated. In the summertime when it’s hot, it’s a good idea to drink less coffee and drink water instead of coffee at work.
  • Alcohol:
    Alcohol is a diuretic which makes you pee more often and dehydrates you. If you do choose to drink alcohol, be aware that you will need to drink more water to stay hydrated.

To learn more about heat illness prevention and hydration, click on the resources below: