Written through Kris Gunnars, BSc — median reviewed by Natalie Butler, R.D., L.D. — update on November 5, 2020

Your human body is about 60 percent water.

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The human body constantly loses water transparent the day, mainly through urine and sweat but additionally from continual body attributes like breathing. To protect against dehydration, you require to gain plenty that water from drink and food every day.

There are numerous different opinions ~ above just just how much water you must be drinking every day.

Health experts typically recommend eight 8-ounce glasses, which equals about 2 liters, or half a gallon a day. This is referred to as the 8×8 rule and also is very easy to remember.

However, part experts think that you must sip top top water constantly transparent the day, even when you’re no thirsty.

As with many things, this depends on the individual. Many factors (both internal and also external) ultimately impact how lot water you need.

This post takes a watch at part water intake studies to separate truth from fiction and explains exactly how to quickly stay fine hydrated for her individual needs.

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How lot water you need depends top top a many things and also varies from person to person. Because that adults, the basic recommendation from The U.S. Nationwide Academies that Sciences, Engineering, and Medicine is about:

11.5 cup (2.7 liters) a day because that women15.5 cup (3.7 liters) a work for males

This contains fluids from water, beverages like teas and also juice, and also from food. You get an average of 20 percent of her water indigenous the foods items you eat (1, 2).

You might need more water 보다 someone else. How much water friend need additionally depends on:

The temperature or season. You might need an ext water in warmer months 보다 cooler ones because of perspiration.Your environment. If friend spend more time the end in the sunlight or hot temperatures or in a heated room, you could feel thirstier faster.How energetic you are. If girlfriend are active during the day or walk or stand a lot, you will do it need more water than someone who sitting in ~ a desk. If you practice or do any kind of intense activity, you will should drink more to covering water loss.Summary

Many factors influence how much water you need to stay healthy such as your health, activity, and also environment.

Many civilization claim that if friend don’t continue to be hydrated throughout the day, your energy levels and brain function start to suffer.

There room plenty of studies to support this.

One examine in women verified that a fluid loss that 1.36 percent after practice impaired mood and concentration and also increased the frequency that headaches (4).

Another research in China that complied with 12 males in university found that not drinking water because that 36 hours had actually noticeable effects on fatigue, attention and focus, reaction speed, and also short-term storage (5).

Even gentle dehydration can reduce physics performance. A clinical examine on older, healthy men report that just a 1 percent lose of human body water decreased their muscle strength, power, and endurance (6).

Losing 1 percent of body weight might not seem like a lot, but it’s a far-ranging amount of water to lose. This typically happens as soon as you’re sweating a lot of or in a really warm room and not drinking sufficient water.


Mild dehydration caused by exercise or heat can have negative effects ~ above both her physical and mental performance.

There room many insurance claims that drinking much more water may reduce body weight by enhancing your metabolism and also curbing appetite.

According come a study, drinking more water 보다 usual associated to a decrease in human body weight and body composition scores. (7).

Another testimonial of studies uncovered that chronic dehydration was connected with obesity, diabetes, cancer, and cardiovascular condition (8).

Researchers in an additional older study estimated that drinking 68 ounces (2 liters) in someday increased energy expenditure by around 23 calories every day as result of a thermogenic response, or a quicker metabolism (9). The amount to be incremental but could add up over time.

Drinking water around a fifty percent hour prior to meals can also reduce the number of calories you end up spend (10). This can happen due to the fact that it’s straightforward for the body to mistake thirst because that hunger.

One study proved that civilization who drank 17 ounces (500 mL) that water before each meal lost 44% much more weight end 12 weeks, contrasted to those that didn’t (11).

Overall, it appears that drinking adequate quantities of water, particularly before meals, may give you a an increase in regulating appetite and maintaining a healthy body weight, especially when merged with a healthy eating plan.

What’s more, drink plenty that water has a number of other health benefits.


Drinking water can cause slight, temporary rises in metabolism, and drinking it around a fifty percent hour prior to each meal can assist you eat under calories.

Both the these results can contribute to load loss in part people.

Drinking sufficient water is forced for your body to role in general. Numerous health difficulties may likewise respond fine to enhanced water intake:


Drinking much more water and also staying adequately sign language may aid with some health problems, such together constipation, urinary and bladder infections, kidney stones, and skin dehydration.

Plain water is not the just drink the contributes to your liquid balance. Other drinks and foods can have a significant effect.

One legend is the caffeinated drinks, such together coffee or tea, don’t assist you hydrate since caffeine is a diuretic.

In fact, studies show that the diuretic effect of these beverages is weak, however they can cause extra urination in some world (19). However, even caffeinated drinks help add water to her body overall.

Most foods items contain water in differing levels. Meat, fish, eggs, and also especially fruits and also vegetables every contain water.

Together, coffee or tea and also water-rich foods items can assist maintain your liquid balance.


Other beverages can add to liquid balance, including coffee and also tea. Many foods additionally contain water.

Maintaining water balance is necessary for her survival.

For this reason, her body has actually a advanced system for managing when and also how lot you drink. As soon as your total water contents goes listed below a details level, thirst kicks in.

This is carefully well balanced by mechanisms comparable to breathing — girlfriend don’t have to consciously think about it.

Your human body knows how to balance that water levels and when come signal you to drink more.

While thirst might be a reputable indicator that dehydration, relying on feeling thirsty may not be adequate for optimal health and wellness or exercise performance (20).

At the time thirst strikes, you may be already feeling the results of too little hydration together as fatigue or headaches.

Using your urine color as your guide can be an ext helpful to know if she drinking enough (21). Aim for pale, clean urine.

There yes, really is no science behind the 8×8 rule. It is fully arbitrary (1, 22). The said, details circumstances may call for raised water intake.

The most important one may be throughout times of boosted sweating. This consists of exercise and also hot weather, especially in a dried climate.

If you’re sweating a lot, make certain to replenish the lost liquid with water. Athletes doing long, extreme exercises may likewise need come replenish electrolytes, favor sodium and also other minerals, together with water.

Your water require increases during pregnancy and also breastfeeding.

You additionally need an ext water as soon as you have a fever and when you vomiting or have diarrhea. If you desire to shed weight, think about upping her water input too.

Furthermore, older civilization may must consciously watch your water intake because the thirst mechanisms deserve to start to malfunction with aging. Studies present that adults over 65 year old are at a greater risk because that dehydration (23).


Most world don’t need to emphasis too lot on their water intake, as the body has an automatically thirst signal.

However, specific circumstances do call for increased attention to exactly how much water you’re drinking.

At the end of the day, no one have the right to tell you precisely how lot water girlfriend need. This counts on countless factors.

Try experimenting to watch what works best for you. Some civilization may function better with more water 보다 usual, while for others it only results in much more frequent trips to the bathroom.

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If you desire to store things simple, these guidelines should apply to the majority of people:

Drink often enough throughout the day because that clear, pale urine.When you thirsty, drink.During high heat and also exercise and also other mentioned indications, make certain to drink enough to compensate for the lost or extra needed fluids.That’s it!

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Written through Kris Gunnars, BSc — medically reviewed by Natalie Butler, R.D., L.D. — updated on November 5, 2020