Lewis
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Do you really need 8 glasses of water a day?
This is in 2 posts
How much water do we really need? You may think six to eight glasses per day because you have probably read many articles and had discussions with your doctor to support that. But a Scottish physician has blasted that standard in a British Medical Journal article, stirring the debate about how much water we should drink and how much is too much and bad for our health.
Dr. Margaret McCartney argues there is no quality scientific evidence to support the recommendation, which she says can lead to over-hydration problems for some people.
Here's what you need to know to sort hydration hype from good health advice.
Don't skimp
The eight-glass formula doesn't fit for everyone. It depends on your gender, size, and level of activity, other studies note. The Institute of Medicine calls for adult men to drink 13 cups of fluid daily (which totals three liters, or a little more than four tall reusable water bottles) and women to have nine cups (2.2 liters, or about the amount found in three reusable water bottles). That number changes according to lifestyle. The more active a person is, the more they will need to replace fluids. Larger people, pregnant and nursing women, and those who take dehydrating medications also will likely need to account for that by adding more water to their diet.
If you are active, it's also important to account for your environment when calculating how much fluid you need. If you are exercising in temperatures that are very hot (likely leading you sweat more) or very cold (which can stunt your ability to sense dehydration), are an endurance athlete, or are active in a high-altitude area, you will probably need to up your water intake.
Related: How much exercise do you really need?
Don't overdo it
The debate about how much water we really need to be drinking is centered around the risk of hyponatremia, or taking in more fluid that the body loses while sweating. It is a serious condition that occurs when there is not enough sodium (or salt) in the body fluids outside of the cells. This can cause swelling, including of the brain. Hyponatremia happens when a person sweats excessively in one stint, does not eat, does not urinate enough, and drinks a great deal of water. Symptoms include confusion, headaches, muscle spasms, vomiting, convulsions, and fatigue. In the worst cases, hyponatremia can lead to seizures, coma, and even death.
There are exceptions for medical conditions and other situations, but athletes are often watched for signs of hyponatremia, especially those participating in endurance events like a marathon or triathlon.
This is in 2 posts
How much water do we really need? You may think six to eight glasses per day because you have probably read many articles and had discussions with your doctor to support that. But a Scottish physician has blasted that standard in a British Medical Journal article, stirring the debate about how much water we should drink and how much is too much and bad for our health.
Dr. Margaret McCartney argues there is no quality scientific evidence to support the recommendation, which she says can lead to over-hydration problems for some people.
Here's what you need to know to sort hydration hype from good health advice.
Don't skimp
The eight-glass formula doesn't fit for everyone. It depends on your gender, size, and level of activity, other studies note. The Institute of Medicine calls for adult men to drink 13 cups of fluid daily (which totals three liters, or a little more than four tall reusable water bottles) and women to have nine cups (2.2 liters, or about the amount found in three reusable water bottles). That number changes according to lifestyle. The more active a person is, the more they will need to replace fluids. Larger people, pregnant and nursing women, and those who take dehydrating medications also will likely need to account for that by adding more water to their diet.
If you are active, it's also important to account for your environment when calculating how much fluid you need. If you are exercising in temperatures that are very hot (likely leading you sweat more) or very cold (which can stunt your ability to sense dehydration), are an endurance athlete, or are active in a high-altitude area, you will probably need to up your water intake.
Related: How much exercise do you really need?
Don't overdo it
The debate about how much water we really need to be drinking is centered around the risk of hyponatremia, or taking in more fluid that the body loses while sweating. It is a serious condition that occurs when there is not enough sodium (or salt) in the body fluids outside of the cells. This can cause swelling, including of the brain. Hyponatremia happens when a person sweats excessively in one stint, does not eat, does not urinate enough, and drinks a great deal of water. Symptoms include confusion, headaches, muscle spasms, vomiting, convulsions, and fatigue. In the worst cases, hyponatremia can lead to seizures, coma, and even death.
There are exceptions for medical conditions and other situations, but athletes are often watched for signs of hyponatremia, especially those participating in endurance events like a marathon or triathlon.
