drink water

Water: Staying Safely Hydrated

Water: How much should you drink every day?

Water is essential to good health, yet needs vary by individual. These guidelines can help ensure you drink enough fluids.

How much water should you drink each day? It's a simple question with no easy answers. Studies have produced varying recommendations over the years, but in truth, your water needs depend on many factors, including your health, how active you are and where you live.

Although no single formula fits everyone, knowing more about your body's need for fluids will help you estimate how much water to drink each day.

Health benefits of water

Water is your body's principal chemical component and makes up about 60 percent of your body weight. Every system in your body depends on water. For example, water flushes toxins out of vital organs, carries nutrients to your cells, and provides a moist environment for ear, nose and throat tissues.

Lack of water can lead to dehydration, a condition that occurs when you don't have enough water in your body to carry out normal functions. Even mild dehydration can drain your energy and make you tired.

How much water do you need?

Every day you lose water through your breath, perspiration, urine and bowel movements. For your body to function properly, you must replenish its water supply by consuming beverages and foods that contain water.

So how much fluid does the average, healthy adult living in a temperate climate need? The Institute of Medicine determined that an adequate intake (AI) for men is roughly about 13 cups (3 liters) of total beverages a day. The AI for women is about 9 cups (2.2 liters) of total beverages a day.

What about the advice to drink 8 glasses a day?

Everyone has heard the advice, "Drink eight 8-ounce glasses of water a day." That's about 1.9 liters, which isn't that different from the Institute of Medicine recommendations. Although the "8 by 8" rule isn't supported by hard evidence, it remains popular because it's easy to remember. Just keep in mind that the rule should be reframed as: "Drink eight 8-ounce glasses of fluid a day," because all fluids count toward the daily total.

Factors that influence water needs

You may need to modify your total fluid intake depending on how active you are, the climate you live in, your health status, and if you're pregnant or breast-feeding.

  • Exercise. If you exercise or engage in any activity that makes you sweat, you need to drink extra water to compensate for the fluid loss. An extra 1.5 to 2.5 cups (400 to 600 milliliters) of water should suffice for short bouts of exercise, but intense exercise lasting more than an hour (for example, running a marathon) requires more fluid intake. How much additional fluid you need depends on how much you sweat during exercise, and the duration and type of exercise.
  • Intense exercise. During long bouts of intense exercise, it's best to use a sports drink that contains sodium, as this will help replace sodium lost in sweat and reduce the chances of developing hyponatremia, which can be life-threatening. Also, continue to replace fluids after you're finished exercising.
  • Environment. Hot or humid weather can make you sweat and requires additional intake of fluid. Heated indoor air also can cause your skin to lose moisture during wintertime. Further, altitudes greater than 8,200 feet (2,500 meters) may trigger increased urination and more rapid breathing, which use up more of your fluid reserves.
  • Illnesses or health conditions. When you have fever, vomiting or diarrhea, your body loses additional fluids. In these cases, you should drink more water. In some cases, your doctor may recommend oral rehydration solutions, such as Gatorade, Powerade or CeraLyte. You may also need increased fluid intake if you develop certain conditions, including bladder infections or urinary tract stones. On the other hand, some conditions, such as heart failure and some types of kidney, liver and adrenal diseases, may impair excretion of water and even require that you limit your fluid intake.
  • Pregnancy or breast-feeding. Women who are pregnant or breast-feeding need additional fluids to stay hydrated. Large amounts of fluid are used especially when nursing. The Institute of Medicine recommends that pregnant women drink about 10 cups (2.3 liters) of fluids daily and women who breast-feed consume about 13 cups (3.1 liters ) of fluids a day.

Beyond the tap: Other sources of water

You don't need to rely only on what you drink to meet your fluid needs. What you eat also provides a significant portion of your fluid needs. On average, food provides about 20 percent of total water intake. For example, many fruits and vegetables, such as watermelon and spinach, are 90 percent or more water by weight.

In addition, beverages such as milk and juice are composed mostly of water. Even beer, wine and caffeinated beverages — such as coffee, tea or soda — can contribute, but these should not be a major portion of your daily total fluid intake. Water is still your best bet because it's calorie-free, inexpensive and readily available.

Staying safely hydrated

Generally, if you drink enough fluid so that you rarely feel thirsty and your urine is colorless or light yellow — and measures about 6.3 cups (1.5 liters) or more a day if you were to keep track — your fluid intake is probably adequate. If you're concerned about your fluid intake or have health issues, check with your doctor or a registered dietitian. He or she can help you determine the amount of water that's right for you.

To ward off dehydration and make sure your body has the fluids it needs, make water your beverage of choice. It's also a good idea to:

  • Drink a glass of water or other calorie-free or low-calorie beverage with each meal and between each meal
  • Drink water before, during and after exercise

Although uncommon, it is possible to drink too much water. When your kidneys are unable to excrete the excess water, the electrolyte (mineral) content of the blood is diluted, resulting in low sodium levels in the blood, a condition called hyponatremia. Endurance athletes, such as marathon runners who drink large amounts of water, are at higher risk of hyponatremia. In general, though, drinking too much water is rare in healthy adults who eat an average American diet.


Avoiding High Cortisol Levels, Depression, Heart Disease, Obesity and Interference With Memory And Learning

What is Cortisol?

Cortisol is a hormone released during the body’s “fight or flight” response to stress. Cortisol prepares the body for physical danger by releasing glucose into the bloodstream, improving the brain’s use of glucose, and increasing the availability of tissue repairing substances. Cortisol also curbs bodily functions that are not essential in emergency situations, such as the immune, digestive and reproductive systems. Prolonged high cortisol can be detrimental to almost all of the body’s processes and can have serious consequences such as heart disease, obesity, depression, and interference with cognitive abilities such as memory and learning.

Severe cases of prolonged high cortisol, such as in major depression, can cause neurotoxicity and brain damage. The condition known as hyper-cortisolemia can destroy cells in the hippocampus, amygdala, and cerebellum. Prolonged untreated cases of stress and depression can lead to the onset of more serious conditions such as incurable depression and bipolar disorder. While anti-anxiety and anti-depressant medications are treatments commonly recommended by medical doctors, here are some ways to attempt to lower cortisol levels naturally.

Identify Cortisol Triggers

The first step in reducing cortisol is identifying the particular stressors in your life that are triggering the release of cortisol so that you can eliminate them. Among some common triggers are lack of adequate sleep, over exercising, and dieting.

Consume Protein at Each Meal

The longer you go without food the more your glycogen reserves get depleted, and protein helps to build these reserves. Incorporate protein into each meal. Eat breakfast that contains protein, as your brain is particularly depleted of its glycogen reserves after sleeping.  Also, inadequate protein intake can disturb sleep which can lead to a spike in cortisol.

Eat Healthy

Avoid sugar and refined carbohydrates, which can cause spikes in insulin production and evoke a stress response. Eat balanced meals consisting of protein, complex carbohydrates and good fats like olive oil and flax seed oil. Diets rich in complex carbohydrates keep cortisol levels lower than low carb diets. Don’t buy into fad diets and don’t let food and eating become a source of stress.

Eat Often

Cortisol levels begin to rise after 5 hours without food. Aim to eat 5 or 6 times daily. Do not diet or overly restrict calories or certain foods. Researchers at Yale University and the University of British Columbia found that women with high levels of “cognitive dietary restraint” (putting a lot of mental energy into restricting certain foods) had significantly higher cortisol levels, bigger appetites, increased consumption of sweets, more negative moods, and higher body-fat levels – even despite getting more exercise.

Drink Water

Dehydration can induce a stress response and spike cortisol levels. Drink water first thing in the morning, as you become dehydrated during sleep. Try not to drink water an hour before bedtime in order to prevent waking up to go to the bathroom which interrupts sleep.

Exercise Moderately 

Exercise helps build muscle mass and increase the brain’s output of serotonin and dopamine, brain chemicals that reduce anxiety and depression. But minimize Prolonged Physical Activity. After an hour of exercise your body’s testosterone levels decline and cortisol begins to rise. Keep workouts to under an hour and do not train more than 2 days in a row.

Avoid Stimulants

Do not consume caffeine-containing coffee, tea, green tea, energy drinks, appetite suppressants, or medications such as Excedrin and Midol. Caffeine directly stimulates the adrenal glands to produce cortisol and interferes with sleep. Avoid herbal stimulants such as ma muang, guarana, synaphrine (zhi shi), yohimbe, quebracho, coleus, and of course ephedrine and amphetamines.

Improve Your Sleep

Ensure a regular sleep pattern: be in bed before 10:30pm and wake up at the same time every day. Avoid exposure to light for a two hour period before bedtime, particularly blue light emitted by electronics such as TVs, laptops, iPads, and blackberries. If evening electronics are necessary, use a blue light filter on the screen. If sleep aids are necessary, take natural forms such as chamomile tea and melatonin. Melatonin can help you sleep deeper and lengthen the sleep cycle. For assistance waking, try a light box that simulates the sun rise instead of a jarring alarm clock.

Stress Reducing Supplements Shown to Lower Cortisol


Glutamine is the most abundant amino acid in muscle cells and it preserves muscle by reducing cortisol levels. In addition, it offers other properties such as an increase in muscle cell volume, increased protein synthesis, enhanced immune function, and increased glycogen replenishment after a workout. Take 5 grams 3 times daily, including before and after working out.

Vitamin C

It has been reported that vitamin C exerts a subtle cortisol-reducing effect on the human body. Vitamin C is water soluble so there is little risk in taking large doses. Take 1 gram (1000 mg), 3 times a day, preferably with breakfast, lunch and dinner (should be meals 1, 3, and 5).


The body’s hormonal stress response causes an outpouring of magnesium from cells into the blood. The higher the stress level, the greater the magnesium loss. The lower your magnesium level is initially, the more reactive you will be to stress (the higher your level of hormones adrenalin and cortisol in stressful situations), which causes greater loss of magnesium from cells. Soaking in a bath of Epsom salts may help. The best dietary supplements are the acid salts of magnesium like magnesium chloride, citrate, gluconate or glycinate.


An amino acid derivative commonly found almost exclusively in green tea, theanine is able to cross the blood-brain barrier and induce relaxation without causing drowsiness. Theanine has psychoactive properties and has been shown to reduce mental and physical stress.

B Complex

B vitamins have been shown to directly affect neurotransmitters in the brain, such as serotonin, norepinephrine and dopamine. Evidence suggests that B-vitamins are important in the balance and metabolism of neuro-toxic chemicals that have been linked to anxiety and depression related conditions. B vitamins maintains the adrenal glands and get used up during the “fight or flight” response and when converting food into energy for the body.

Omega 3 Fatty Acids

Omega 3’s have a calming effect on the central nervous system and have been proven effective at reducing cortisol levels. Researchers in France investigated the effects of fish oil, which contains the omega 3 fatty acids EPA and DHA, on mental stress in men and found that fish oil significantly reduce cortisol levels after undergoing a mental stress test that measured blood levels of epinephrine and cortisol (among others).

Phosphatidylserine (PS)

PS is a cortisol blocker that drives nutrients into and remove toxins from your cells. It may be useful in preventing short-term memory loss, age-related dementia and Alzheimer’s disease.

Stress Reducing Lifestyle Choices

Change Your Stress Response 

The mind can exert a direct influence on the immune system. “The brain has the capacity to modulate peripheral physiology,” says Dr. Richard J. Davidson, director of the University of Wisconsin’s Laboratory for Affective Neuroscience, “and it modulates it in ways that may be consequential for health.” Research has shown that humans can “think” themselves in or out of stress and therefore, their state of health.

Examine circumstances in your daily life that elevate heart rate, blood pressure and tension and try to be conscious that these physical responses are unnecessary to alleviate the circumstance at hand. Practice patience, deep breathing, and an outlook of acceptance and surrender. Relinquish the need to control other people and circumstances. View adversity as an opportunity for learning and growth. Books such as Stillness Speaks and the Power of Now by Eckhart Tolle discuss new methods of thinking that can de-clutter the mind and encourage stillness, peace and what he calls “the joy of Being.”

Change Your Outlook

Try allocating 10 minutes each day to either think, discuss, or write down the things and people in your life you are grateful for. Give compliments. Radiate positivity in order to attract positive and supportive people in your life.

Seek Emotional Support

Emotional pain can induce chronic daily stress – the most damaging form. Do not repress or bury emotions, unresolved emotions can resurface as nightmare or manifest into physical illness. Talk therapy with a counselor or psychotherapist, as well as maintaining close personal relationships is important. End stressful relationships and don’t engage in gossip or other negative conversations.

Get Outside

Recently, the antidepressant effect of high-density negative air ions has been observed in patients with chronic depression. Patients can promote their exposure by spending more time where negative air ions are found naturally – in humid, vegetated environments and at the seashore. Negative air ions are lower in urban environments and heated or air conditioned interiors. Studies have reported that access to green space within a mile of one’s residence is associated with improved mental health. Large population studies show that those with the least green space within one mile of home have a 25% greater risk of depression and a 30% higher risk of an anxiety disorder.

Get Organized

Manage time by carefully scheduling each task, chore, meeting, and appointment. De-clutter your office and home environment. Do not procrastinate!

Schedule Time For Relaxation

Incorporate activities such as meditation, massage, and yoga into your daily routine to encourage a regular pattern of de-cluttering the mind. If you have problems keeping commitments to leisure activities, it may take formally scheduling them into your workday, signing up with a friend, or paying for classes in advance.

Reduce your Morning Commute

Studies show higher cortisol levels in people with longer morning commutes. Using public transportation instead of driving can reduce stress induced by traffic jams. Other habits that may help make your commute more fun include carpooling, music, and choosing a slightly longer but less congested route.