True or false: We need 8 glasses of water per day

By The Health News Team | December 15, 2023
Friends drinking water while exercising

Living in San Diego often means outdoor fun, sunshine and hot temperatures — regardless of the time of year. That’s why it’s important to properly fuel your body and look out for early signs of dehydration throughout spring, summer, winter and fall.

The message used to be simple: Drinking water is good and not drinking water is bad. But somehow, this message became complicated. It’s often hard to distinguish hydration facts from myths.

Melissa Hughes, a registered dietitian nutritionist, certified wellness and health coach, and program manager for the Sharp Rees-Stealy Center for Health Management, helps clarify the latest hydration hype.

Why is it important to stay hydrated?
Water is life — almost every system of the body depends on it to function and survive. Water removes toxins from the body, helps regulate body temperature, and aids in many other important functions. During the hot days, it’s especially important to stay hydrated, as we lose water quicker when the sun is out, temperatures rise, and we sweat more.

Do you need to drink 8 cups of water a day?
This is a broad recommendation, but a good goal. The exact amount of water you need to drink varies based on factors such as age, gender, height and weight. People who are pregnant or breastfeeding; very physically active; outside in hot and humid weather; or who have certain medical conditions, including kidney stones, a bladder infection, or an illness that causes vomiting or diarrhea, may need more than 8 glasses of water per day.

Does water flush out toxins from your body?
Yes, water carries waste out from the body. The kidneys use water to filter waste from the blood and carry water-soluble toxins from the liver. These toxins are eliminated in the urine.

Does caffeine dehydrate you?
Caffeine does have a weak diuretic effect, but moderate caffeine consumption does not increase the risk of dehydration.

Does clear urine mean you’re hydrated?
Urine color is an indicator of hydration. Clear urine means you’re eliminating water, which may mean you’re drinking more water than you need. A very light-yellow color means the body is well hydrated. The deeper the color of the urine, the more dehydrated the body. Seek medical attention if urine has a dark amber or brown tint.

Can a person drink too much water?
It’s really difficult to drink too much water. Rare cases of overhydration can cause hyponatremia, which is a critically low level of sodium in the blood. Symptoms are similar to heat exhaustion and include headache, diarrhea, nausea and vomiting.

Is being dehydrated a big deal?
It’s important to stay well hydrated — especially during heat waves. Symptoms of early dehydration include dark urine, weakness, cramping and headache. Moderate symptoms of dehydration include low blood pressure; fainting; a fast, weak pulse; and rapid and deep breathing.

Hughes offers these tips for staying hydrated:

  1. Keep water nearby. Take a refillable water bottle with you — it’s a good reminder to drink water throughout the day.

  2. Infuse your water. If you get tired of plain water, try making spa water by adding fresh fruit, vegetables or herbs to your pitcher, cup or bottle. Chopped watermelon and basil or fresh blueberries and mint make delicious flavor combinations.

  3. Eat your water. While not a substitute for water, some fruits and veggies can help your effort to stay hydrated. Fruits and veggies with high-water content include melons, strawberries, cucumbers and bell peppers.

“The body is made up of about 60% water,” says Hughes. “So staying hydrated is absolutely essential to health.”

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