Summer is the time for outdoor fun and activities, but as temperatures rise, staying properly hydrated becomes even more important. Even if you are not engaged in strenuous activity, you will sweat more in the heat and humidity. Even mild activity will increase your body temperature and your body’s need to sweat.



All of this water needs to be replaced, but remember that when you sweat, you are not just losing water, you are losing minerals such as sodium and potassium which also need to be replaced. This is why athletes and runners drink sports drinks like Gatorade rather than just water. Replacing water without sufficient sodium can quickly produce hyponatremia, a potentially fatal condition.



Hyponatremia symptoms are similar to those of heat exhaustion and heat stroke and are often overlooked. Sometimes people drink more water when they start having these symptoms and end up making their condition worse. Symptoms range from mild to severe and can include nausea, muscle cramps, disorientation, confusion, seizures, coma and death.



There have been several cases of illness and even deaths from hyponatremia over the past several years. According to the British Medical Journal, 16 runners have died as a result of too little sodium and over-hydration, while another 1,600 have become seriously ill. It is true that water intoxication is more commonly seen among extreme athletes, but older individuals are also at high risk for several reasons.



Ideally, anyone engaging in outdoor activity in the heat or even an indoor exercise program should drink eight to 12 ounces of fluid every 15 to 20 minutes during a session. If exercising exceeds an hour, a beverage that contains salt and an energy carbohydrate is far superior to plain water. The recommended concentration of salt in a fluid replacement beverage is a quarter teaspoon per liter. Most sports drinks contain salt, although the amount is not quite that high. Anyone can make an alternative to commercial fluid replacement beverages easily by adding a quarter to a half teaspoon of salt per liter or 32 ounces of water.