A how-to guide for hydration

A how-to guide for hydration

We’re constantly told to stay hydrated. Few people, however, understand why it’s so important. To add to that, aside from drinking more water, it’s sometimes hard to tell if you’re getting it right.

Let’s start with the basics. Since your body is largely made up of water—losing even a small percentage can tip the scales toward dehydration and other problems. In fact, being only 2 percent dehydrated can lead to symptoms.

“By weight, the human body is fifty- to sixty-five percent water,” says Catherine LaBella, senior clinical dietitian of food and nutrition at Advocate Lutheran General Hospital in Park Ridge, Ill.

“Water is necessary for countless chemical reactions as well as critical functions, like maintaining body temperature and removing waste,” explains LaBella.

Get your fill

Maintaining hydration throughout the day helps keep the body running like a well-oiled machine. LaBella recommends that you keep a bottle of water nearby and drink some whenever you feel thirsty. If plain water doesn’t interest you, try flavored water. “Just add some sliced cucumber or fruit, like lemon, lime or strawberry, and allow it to sit overnight in the fridge,” she says.

Water is not the only option for hydration. Vegetable and fruit juices, herbal tea and milk also contribute fluid, as well as coffee, tea, and yes, even soda. LaBella does caution about caffeinated beverages though. “Caffeine (found in coffee, tea, some sodas and energy drinks) can be dehydrating so do not make these beverages your main fluid source,” she says.

Staying hydrated means knowing how much water your body needs. So how much is enough? The short answer? It depends, as fluid needs vary.

“Generally, people should drink when they are thirsty to maintain adequate hydration,” says LaBella and adds that thirst is now believed to be an indicator of under-hydration as opposed to dehydration.

Medical necessity
Hydration is important for those with certain medical conditions such as kidney stones and bladder infections. Populations such as pregnant and breastfeeding women need additional fluid along with those who exercise or work outside in hot weather.

Sometimes people get a bit carried away with taking in too much water, which is overhydration. “There is no reason to overhydrate as hyponatremia, a low level of sodium in the blood, can result with excessive fluid intake,” explains LaBella.

This condition is sometimes seen with distance athletes like marathoners but can happen to anyone who drinks far more than their body needs.

Certain other medical conditions, such as heart, liver or kidney disease, may actually require fluid restrictions. “These patients may be on medications to remove water (diuretics) and need to follow their doctor’s orders to keep an appropriate fluid balance for their particular medical condition,” LaBella says.

It’s important, adds LaBella, to always check with your physician before radically altering your fluid intake, especially if you have any medical issues.

The other end of the spectrum
Understand how much hydration your body requires means learning how to prevent dehydration, which can be caused by more than just sweating. “Some water is also lost from the body with every breath you take,” LaBella says. Diarrhea, vomiting, fevers and some medications can cause dehydration. Alcohol can also contribute to it as well.

It’s important to know what signs indicate dehydration. “The easiest way to monitor your hydration level is to keep an eye on your urine,” LaBella says.

Making less urine or darker urine can indicate dehydration or some medical conditions. Other signs of dehydration include:

  • Headache
  • Thirst
  • Dry mouth
  • Lightheadedness/dizziness

“Left untreated, dehydration can cause serious medical issues, and in severe cases, can be life-threatening,” LaBella says.

When your body has the proper amount of hydration, you feel better and your body works better. Drink up!

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  1. Nice write up. Keeping a Nalgene on you will do wonders for keeping you hydrated.

  2. The article does not state how much water you should drink, or did I miss it in the article. My rule of thumb is to drink 1/2 your body weight in ounces of water.

    • Hi, Vera,

      Since it varies with each person, it’s best to just measure your own hydration needs individually. Eight glasses a day is a good rule of thumb, but again, it varies from person to person.

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health enews Staff
health enews Staff

health enews staff is a group of experienced writers from our Advocate Health Care and Aurora Health Care sites, which also includes freelance or intern writers.