Too Much Water Is Worse Than Not Enough

It’s likely you’ve heard of the “8X8 rule” — the belief that you should drink eight 8-ounce glasses of water a day to stay hydrated. While that “rule” is not backed by scientific evidence, staying hydrated is still important. Making up around two-thirds of our body weight, water carries nutrients and waste products around our bodies, regulates our temperature, acts as a lubricant and shock absorber in our joints and plays a role in most chemical reactions happening inside us. However, too much fluid consumption can become serious. Over the last decade, there have been at least 15 cases of athletes who have died from over-hydration during sporting events. These cases are partly because we’ve become distrustful of our own thirst mechanism and think we need to drink more than our bodies are calling for to avoid dehydration. Too much fluid causes a dilution of sodium in the blood, which creates a swelling of the brain and lungs as fluid shifts to try to balance out blood sodium levels. The maximum a person in the hottest possible heat in the middle of the desert might sweat is two liters in an hour. When going through your normal daily routine, including gym workouts, you’re never going to get hot enough to sweat at that rate, even if you’re dripping with sweat. Most experts agree that our fluid requirements vary depending on a person’s age, body size, gender, environment and level of physical activity, but it’s important to remember that our thirst mechanisms lose sensitivity once we’re over 60. As we age, we may need to be more attentive to our fluid consumption habits to stay hydrated. Still, there is no set amount we need to be drinking. Our bodies will signal us when we’re thirsty, just like they do when we’re hungry.