What Is Hyponatremia

Hyponatremia, also called water intoxication, is generally the result of drinking excessive amounts of plain water which causes a low concentration of sodium in the blood. Once a rare occurrence at sporting events, it is becoming more prevalent as participation increases and more novice exercisers are entering endurance events.

Prolonged and excessive sweating increases the risk that an athlete will alter the delicate balance of blood-sodium concentration. Because sodium is lost in sweat it is important for those exercising at high intensities for long periods of time to replace any loses.

Research has found that long duration endurance events, such as the Ironman distance triathlons, often have finishers with low blood sodium concentrations. Those at most risk are those who are on the course the longest, because they tend to drink the most water during the event. Runners who drink extra fluids in the days before the race or those who stop at water stop during the race are also at increased risk of hyponatremia. In fact, a study published in the New England Journal of Medicine (April, 2005) found that 13 percent of Boston Marathon runners developed hyponatremia from drinking too much water.

Causes of Hyponatremia
During high intensity exercise, sodium is lost along with sweat. An athlete who only replaces the lost fluid with water will have a decreased blood-sodium concentration. As an example, consider a full glass of salt-water. If you dump out half of the contents of the glass (as is lost in sweat), and replace that with water only, the sodium concentration of in the glass is far less and the water is more dilute. This can occur in the bloodstream of an athlete who only hydrates with water during excessive sweating. The result is hyponatremia.

Adequate sodium balance is necessary for transmitting nerve impulses and proper muscle function, and even a slight depletion of this concentration can cause problems. Studies have shown that high intensity athletes can lose up to 2 grams of salt per liter of sweat. Replacing this during the event is critical to performance and safety.

Symptoms of Hyponatremia
The early warning signs are often subtle and may be similar to dehydration and include nausea, muscle cramps, disorientation, slurred speech, and confusion. At this point, many athletes drink more water because they think they are dehydrated. Unfortunately, water alone will increase the problem of hyponatremia. At the most extreme an athlete may experience seizures, coma, or death.

Treatment of Hyponatremia
At the first sign of symptoms an athlete should drink a sodium containing sports drink or eat salty foods. Ideally, an athlete should plan ahead and estimate his or her fluid loss and need for sodium replacement during the event, and stay on a hydration schedule during the race. If the symptoms are extreme, a medical professional should be seen.

Preventing Hyponatremia
The best way for an athlete to avoid such problems is to plan ahead by training in the same conditions you will encounter during race day. Hydration recommendations include:

How Much Water Should You Drink?.

Calculate your water intake with this simple formula.
Use a sodium containing sports drinks during long distance, high intensity events (more than 60-90 minutes long).
Increase salt intake per day several days prior to competition (except for those with hypertension).
Try not to drink more then you sweat.
During a marathon a good rule of thumb is to drink about 1 cup of fluid every 20 minutes.
In the days before the race, add salt to your foods (provided that you don't have high blood pressure and your doctor has not restricted your salt intake).
Avoid use of nonsteroidal anti-inflammatory (NSAIDS) medicines that contain sodium. Research suggests that these drugs may predispose runners to hyponatremia.
Keep in mind that all athletes respond differently to exercise; fluid and sodium needs will vary accordingly. Foods that provide additional sodium include chicken noodle soup, a dill pickle, cheese, pretzels, and tomato juice.

As always, it is important to consult your physician for special considerations if you have a history of any health problems or are taking any medication for a health condition.

Are there any abnormal conditions which cause us to drink more water?

If you are sitting outside in a humid and warm weather it is likely that you will sweat a lot. If you keep drinking copious amounts water you will so start feeling a bit sluggish because of lowered electrolytes in your body.

Always compensate for the salts lost through your body by consuming food or a saline solution. Sport drinks are becoming popular for this very reason. They compensate the body for electrolyte lost along with water.

If you are continuously drinking water through habit, it can be harmful for the kidneys. The signs of drinking too much water become evident when you have to visit the washroom every few minutes.

Overhydration Vs. Dehydration

Advice about preventing dehydration is especially prevalent during the hot summer months when the amount of fluid lost through sweat can reach dangerous levels. There is another danger related to hydration that is lesser known, hyponatremia, a potentially fatal condition that can result from drinking too much water.

When too much water is consumed, sodium levels can reach dangerously low levels, leading to a condition known as hyponatremia. Endurance athletes are at a particularly high risk for hyponatremia, also called "water intoxication" or  exercise associated hyponatremia. In a 2002 study of 488 Boston Marathon runners, 13 percent had hyponatremia at the end of the race.

How Fast Vs. How Much Water You Drink

The kidneys of most healthy adults can process up to 15 quarts of water a day!

Since most people are never going to drink anywhere near that amount, it is highly unlikely that you are ever going to become water intoxicated.

Dehydration from insufficient water intake and/or water loss affects a much, much higher percentage of people than water intoxication.

The danger of drinking too much water is not so much about how much water you drink, but how fast you drink it, as noted in the case with the California woman.

It is better to have small amounts of water frequently rather than trying to force large amounts of fluid at one time.

Thus, the bottom line is that drinking too much water is not an issue for most people—as long as one’s water intake is spread throughout the day.

Special considerations are noted for infants, athletes or other individuals with medically diagnosed conditions that require limited intake of fluids. As always, follow your doctor’s recommendations.

So how much WATER should you drink to best support your health?

The answer to this question depends on your unique circumstances, including your diet, exercise habits, and environment.


If you eat plenty of foods that are naturally rich in water, such as vegetables, fruits, and cooked legumes and whole grains, you may not need to drink very much water at all. If you do not use much or any salt and other seasonings, your need for drinking water goes down even further.


Conversely, if you do not eat a lot of plant foods and/or you add substantial salt and spices to your meals, you may need to drink several glasses of water every day.


Regardless of what your diet looks like, if you sweat on a regular basis because of exercise or a warm climate, you will need to supply your body with more water (through food and/or liquids) than someone who does not sweat regularly.


Ultimately, the best guidance I can provide on this issue is to follow your sense of thirst. Some people believe that thirst is not a reliable indicator of how much water you need, since many people suffer with symptoms related to dehydration and don't seem to feel a need to drink water on a regular basis. My experience has been that most people who are chronically dehydrated have learned to ignore a parched mouth. If you ask such people if they are thirsty and would like a piece of fruit or a glass of water, they will almost always realize that they are indeed thirsty.


Some people suggest observing the color of your urine as a way of looking out for dehydration. The idea is that clear urine indicates that you are well hydrated, while yellow urine indicates that you need more water in your system. While this advice is somewhat useful, it is important to remember that some chemicals (like synthetic vitamins) and heavily pigmented foods (like red beets) can add substantial color to your urine. Thumbs down for synthetic vitamins, and thumbs up for red beets and other richly colored vegetables and fruits.


The main idea that I wish to share through this article is to beware of mindlessly drinking several glasses of water per day without considering your diet, exercise habits, climate, and sense of thirst. And when you do find yourself in need of water, remember that you can get it from liquids and/or whole foods.


Please share this article with family and friends, as many people are regularly misinformed on this topic by mainstream media and health practitioners.

Why Drinking Too Much Water Is Dangerous?

On January 12, 2007, a 28-year old Californian wife and mother of three children died from drinking too much water. Her body was found in her home shortly after she took part in a water-drinking contest that was sponsored by a local radio show. Entitled "Hold Your Wee For A Wii," the contest promoters promised a free Wii video game machine to the contestant who drank the most water without urinating.

It is estimated that the woman who died drank approximately 2 gallons of water during the contest. When she and other contestants complained of discomfort and showed visible signs of distress, they were laughed at by the promoters and even heckled.

This tragic news story highlights the importance of understanding why drinking too much water can be dangerous to your health.

Whenever you disregard your sense of thirst and strive to ingest several glasses of water a day just because you have been told that doing so is good for your health, you actually put unnecessary strain on your body in two major ways:

1. Ingesting more water than you need can increase your total blood volume. And since your blood volume exists within a closed system - your circulatory system - needlessly increasing your blood volume on a regular basis puts unnecessary burden on your heart and blood vessels.
2. Your kidneys must work overtime to filter excess water out of your circulatory system. Your kidneys are not the equivalent of a pair of plumbing pipes whereby the more water you flush through your kidneys, the cleaner they become; rather, the filtration system that exists in your kidneys is composed in part by a series of specialized capillary beds called glomeruli. Your glomeruli can get damaged by unnecessary wear and tear over time, and drowning your system with large amounts of water is one of many potential causes of said damage.

Putting unnecessary burden on your cardiovascular system and your kidneys by ingesting unnecessary water is a subtle process. For the average person, it is virtually impossible to know that this burden exists, as there are usually no obvious symptoms on a moment-to-moment basis. But make no mistake about it: this burden is real and can hurt your health over the long term.

Forcing your body to accept a large amount of water within a short period of time - say, an hour or two - as several contestants did during the "Hold Your Wee for a Wii" contest can be fatally dangerous to your health. Here's why:

If you force large amounts of water into your system over a short period of time, your kidneys will struggle to eliminate enough water from your system to keep the overall amount at a safe level.

As your circulatory system becomes diluted with excess water, the concentration of electrolytes in your blood will drop relative to the concentration of electrolytes in your cells. In an effort to maintain an equal balance of electrolytes between your blood and your cells, water will seep into your cells from your blood, causing your cells to swell.

If this swelling occurs in your brain, you'll experience increased intracranial pressure i.e. your brain will get squeezed because the flat bones that make up your skull don't provide much give. Depending on how much water your drink in a short period of time, you could experience a wide variety of symptoms, ranging from a mild headache to impaired breathing. And as occurred recently in the tragic water-drinking contest, it is quite possible to die if you drink enough water in a short enough period of time.

This information is particularly important for parents to pass on to their children. Foolish water-drinking contests are not uncommon among high school and university students, especially while playing cards.