The human body is approximately 60% water. Through sweating, urinating — and even breathing — the body constantly loses water, meaning that we must regularly consume more in drink and food to prevent dehydration

Despite being essential for health and wellness, water is often a neglected part of our diets. Did you know that a mere 22% of American adults drink the recommended amount of water every day? While the USDA recommends 8 to 10 8oz glasses per day, the average person living in the USA drinks only 5.

The 8×8 rule (8 ounces 8 times a day) is easy to remember, but there are many different opinions on how much and how often you should drink water to stay in optimum health.  

Overall, the amount of water a person needs depends on individual factors, including age, weight, health, and lifestyle. This article will take a detailed look at recommendations for water intake and ways to stay hydrated. 

What Are the Standard Water Intake Recommendations?

If you find yourself wondering ‘how much water should I drink,’ the standard guidelines are pretty straightforward. According to the U.S. National Academies of Sciences, Engineering, and Medicine, you should aim for 11.5 to 15.5 cups of water a day. 

What Factors Affect How Much Water I Should Drink? 

water drinkers

While the 8×8 rule or 11.5-15.5 cups rule are both strong starting points when it comes to your individual water intake, how much you should really be drinking depends on several factors. 

Your fitness levels, age, sex, lifestyle, and location will all alter how much water you need every day. Here we take a closer look at some main factors that influence the amount of fluid you should drink. 


Males tend to need more water than females due to their statistically larger body size. According to the Institute of Medicine, females should drink around 95 ounces a day, while males require 131 ounces. 

This isn’t the amount of plain water you should be drinking, but rather the amount of water you should consume overall. Water is found in many foods, which contributes to your overall water intake. 

However, your total should include a large amount of plain water (or water included in beverages rather than food). When it comes to drinking water, females should have around 9 cups a day, while men should aim for 13 cups.


Your age will also play a large part in determining how much water your body needs to stay fit and healthy. These are the current recommendations from the National Academies of Sciences, Engineering, and Medicine for how much water you should drink based on age. 

Male Adult (19 years and above)13 cups (total of 104 ounces)
Female Adult (19 years and above)9 cups (total of 72 ounces)
Young Infant (4-8 years)5 cups (total of 4 ounces)
Child (9-13 years)7 to 8 cups (total between 56-64 ounces)
Teenager (14-17 years)8 to 11 cups (total between 64-88 ounces)

In summary, younger children need less water, and the amount needed gradually increases with age. Adults should aim for around 10 cups of water per day, although a slightly higher amount is needed for men. 

Pregnancy and Breastfeeding

Recommendations change if you’re breastfeeding or pregnant, and it’s important that you take on enough fluid to keep yourself and your child sufficiently hydrated. 

When pregnant, the body has a higher blood volume and needs to support the amniotic fluid and fetus, thus requiring more water. Several studies show that female water intake should increase to 80 ounces a day or 8 to 10 glasses of liquid. 

Breast milk is 90% water, and while studies have suggested that a nursing mother doesn’t need to drink a huge quantity of additional H20, the Institute of Medicine suggests around 13 cups a day.

Breastfeeding mothers often feel thirstier and hungrier anyway, so they are likely to take on the additional fluids without making a conscious effort.


When we exercise, we lose lots more water than usual through our sweat and breathing. Therefore, it’s important to drink additional fluid to maintain hydration. 

According to one expert, you should adapt your water intake when exercising as follows:

1-2 hours pre-workoutDrink 15-20 ounces
15 minutes pre-workoutDrink 8-10 ounces 
During a workout at 15-minute intervalsDrink 8 ounces per 15 minutes

Overall, an additional 1.5-2.5 cups per day should be enough extra water for a workout of an hour or less. 


Illnesses that involve vomiting and diarrhea leave us dehydrated. That’s because the body begins to lose more fluid than it can take on, and many bodily systems cannot function properly. 

When unwell with these symptoms, you should drink lots of water, although the exact amount depends on the severity of the illness and how much fluid you are losing. 

Do note that water alone won’t replenish your body with the salts and electrolytes it needs to maintain balance. When unwell with vomiting and diarrhea, take oral rehydration medications to restore salts to the body. 


Warmer environments require greater water intake due to the simple fact that we sweat more in the heat. 

Some studies have shown that being dehydrated causes the body to store heat, making it less able to deal with heat strain. This means that whether you live in a hot climate or are simply going on vacation, you should drink extra water to account for the heat. 

The good news is that we naturally feel more thirsty in the heat, so your body should give you regular reminders to keep it topped up with water.

What are the Benefits of Staying Hydrated? 


Most people know that they need to drink water to survive and that it’s important to take on extra fluids when in a hotter environment. But, on a day-to-day basis, we might not feel the benefits of having adequate water levels in our systems. 

Simply drinking fluids works wonders for our bodies in several different ways. From skin complexion to dieting, it can help us out in many fascinating and often unexpected ways. Here we take a look at just some of the key benefits staying well-hydrated can offer you. 

Regulating Body Temperature

Hydration is essential in maintaining the correct body temperature. When you get hot, the body sweats to keep you cool. If you do not replace the water lost, your temperature will rise. By staying hydrated, your body can maintain its temperature and keep all bodily systems functioning at optimum capacity.

Preventing Muscle Fatigue

When you don’t have enough water in your system, cells cannot maintain their balance of fluids, and electrolytes begin to shrivel. This results in muscle fatigue, severely impeding performance, and potentially leading to long term injury.

It isn’t surprising that hydration is important for muscle strength and resilience, given that muscle is around 80% water. By maintaining the right fluid levels when exercising, you can help prevent injury and improve performance.

Eliminating Waste Efficiently

Your body uses water to urinate, have bowel movements, and sweat. All of these processes are essential for removing unwanted waste from the body. Adequate liquid intake will prevent constipation, help the kidneys work efficiently to filter our waste through urination, and help you sweat to control your temperature. 

Revitalizing Complexion

The skin is the body’s largest organ, and it requires plenty of water to keep it looking plump, fresh, and healthy. Dehydrated skin often looks wrinkled and dry, but this damage can be reversed by drinking sufficient fluids every day. 

It is also thought that water can help with a range of general skin problems such as acne, although more research is needed on the subject. 

Controlling Calories 

Water is a dieter’s best friend. While it won’t make you lose weight overnight, it is a great substitute for higher-calorie alternatives and can help you stay feeling full.  

Foods that are rich in water offer healthy alternatives to high-calorie foods. They also have a higher volume, require more chewing, and look larger, which all help us feel replete. Vegetables, fruits, beans, oatmeal, and broth are all water-rich foods that provide a healthy meal without the extortionate calorie count. 

  • Further, one study has shown that drinking above-average amounts of water correlated with decreased bodyweight, while another suggests that drinking before eating helps you eat less. Overall, drinking a healthy amount of water is a great way to help you manage your appetite.

What Are the Signs of Dehydration? 

Dehydration is most frequently caused by illness. Not drinking enough (especially when in the heat or exercising) can lead to dehydration. The symptoms of dehydration include: 

  • Feeling excessively thirsty
  • Tiredness and lethargy
  • Dizziness and nausea
  • Sweating less than usual
  • Urinating less than usual
  • Abnormally dark urine
  • Dry mouth
  • Dry skin

Dehydration can be a serious illness, so you must be familiar with the signs and symptoms. Contact a healthcare professional if you may be suffering from severe dehydration. 

The good news is that you can avoid becoming dehydrated (unless caused by illness) by always being conscious of your fluid levels. Why not try a downloadable app on your smartphone to log your water consumption, or try an incremented drinking bottle that keeps track of your fluid intake for you? 

What Are the Signs of Adequate Hydration? 

While dehydration can make you feel unwell very quickly, it’s harder to know whether you’re drinking enough water. The human body has developed a complex system for controlling the amount you drink and how often. Simply put, when your water content is too low, you will begin to feel thirsty. 

However, some experts suggest that thirst alone is not an adequate signal for dehydration, particularly for exercise or optimal health. Ideally, you should try to top up your water levels before thirst kicks in. By the time you are thirsty, you may already be feeling the side effects of low hydration, such as headaches. 

Urine color that is pale and clear is a sign of adequate hydration. However, you should be aware that this is not a universal rule and dark urine isn’t always a symptom of dehydration. We’ll look at this in more detail later on.

The best way to stay hydrated is to consider your individual situation and work from there. You should aim to drink the standard recommendation for your age and sex in the first instance, and then consider other factors that may alter how much you need to drink. 

The most important time you may need to adjust fluid intake is when you experience increased sweating levels. This may be due to regular exercise or being in a hot, dry climate. 

If you’re pregnant or breastfeeding, you’ll need extra water as well, so make sure you factor this in. Illness also depletes our water supplies, so it’s important to up your water intake when unwell. 

Tips to Up Your Water Intake

If you feel you are not drinking enough, fear not. It’s easy to up your water intake to a healthy amount with a little thought and preparation. Instead of wondering, ‘how much water should I drink?’ you can try the following tactics to keep your intake levels high: 

• Use a reusable water bottle and take it wherever you go. Place it in your car, in your bag, or at your work desk to remind you to keep drinking. 

• Have a drink with every meal or snack throughout the day.

• Choose drinks that actually meet your needs, rather than drinking things you don’t like. Opting for beverages you enjoy will make you more inclined to drink. Further, choose drinks that suit your health and lifestyle goals. If you’re looking to lose weight, choose low-calorie options or just plain water.

• Use an app on your smartphone to log your fluid intake. This can motivate you to meet your goals and drink enough liquid. Incremented water bottles with quantities marked on the side can also help you feel motivated to drink the required amount. 

•Up your fruit and vegetable intake. While the body’s main source of H20 is liquid, we also get some of our fluid from foods, and fruit and vegetables have particularly high water content.

Water Intake Studies: Fact or Fiction? 

There is such a wide variety of information about water and health that it can be hard to separate fact from fiction. You may have heard several competing ‘facts’ about how much water you should be drinking when you should drink it, how to tell if you’ve had enough water, and what it can do for you. 

This section takes you through some common beliefs about water and hydration to see what the science says about each one.

Can Drinking Water Help You Stay Healthy? 

Yes, scientific studies show that adequate fluid intake can help a range of bodily systems run efficiently and contribute to your overall health and wellbeing. 

According to recent research, constipation, kidney stones, and urinary tract infections (UTIs) can be aided by adequate fluid levels. Water is also essential for brain function, which we’ll look at in more detail below. 

Is Urine a Reliable Indicator of Hydration Levels?

A popular belief is that you can tell whether you’re hydrated based on your urine color. Darker urine is commonly thought to be a sign of dehydration, and in some cases, this is true.

However, research by the American College of Sports Medicine suggests that this may be misleading. Vitamins, certain foods, supplements, and medications can all alter the color and tone of urine. Further, environmental factors such s the amount of water in the toilet bowl can alter how dark it’s perceived.

Overall, you shouldn’t overthink this. If you know you have been drinking lots of water, but your urine is still dark, it shouldn’t set alarm bells ringing. Aiming for pale urine when you’re already drinking enough could lead to drinking too much. 

Can You Drink Too Much Water?  

Yes, you can drink too much water. A condition called hyponatremia occurs when the blood is over diluted with H20. This results in dangerously low sodium levels and excessively high water levels, leading to cells beginning to swell.

Hyponatremia symptoms include fatigue, headaches, nausea, muscle weakness and cramps, and in severe cases, comas and even death. It is therefore essential to follow standard guidelines for staying hydrated and not drink excessively.

Does Hydration Affect Brain Function and Energy Levels?

It is a common belief that not drinking enough water can negatively impact mood, concentration, and energy levels. Based on the available research, this seems to be a credible belief.  

A recent study of young women suggested that even minor fluid loss during exercise hurt concentration and mood afterward. Meanwhile, a study on university students in China discovered that not drinking water over a 36-hour period affected reaction speed, attention, fatigue, and short-term memory. 


How much water should I drink?

It really depends on your personal circumstances and individual characteristics. Every human is unique, and our H20 intake should be adapted to our body’s needs on any particular day or in any particular circumstance. 

Ultimately, water is not only what sustains human life but is also one of the most important elements of our diet for health and wellbeing. Remember to keep track of how much you’re drinking, drink regularly, and top up fluid levels in high heat or during exercise. 

If you have any concerns about your hydration levels or health-related issue regarding fluid intake, always contact your healthcare professional.