Is there such a thing as “drinking too much water”? You might be surprised to learn that there really is.
Even though our bodies are (usually) made up of between 45% and 65% water, you really can overdo it when it comes to chugging down the good stuff.
While plenty of people have the opposite problem and find themselves mysteriously thirsty at the end of the day, it’s worth remembering that you can flood your body by drinking too much H2O – although it’s rare for healthy adults to do this.
It may occasionally happen with athletes after exercising, as well as anyone who struggles with schizophrenia, or who takes diuretics, antipsychotic drugs or MDMA.
People who suffer from congestive heart failure, liver disease, kidney problems, uncontrolled diabetes or syndrome of inappropriate antidiuretic hormone (SIADH) are also at a higher risk of being over-hydrated.
According to US-based website Healthline, when you drink too much water, your kidneys end up struggling to remove the excess (this can also happen if you have a kidney condition where they retain too much water).
This is known as water toxicity or water poisoning, and is a severe form of hyponatremia (where there’s an electrolyte imbalance in the body).
If the amount of sodium in your blood can become too diluted, it can be life-threatening.
With decreased sodium levels, fluids move inside your cells, leading to inflammation – this can mean a major problem for your brain.
As Healthline explains: “Ultimately the swelling of brain cells will cause your central nervous system to malfunction. Without treatment, you can experience seizures, enter into a coma, and ultimately die.”
If untreated, it could cause permanent brain damage and death.
What are the symptoms of over-hydration?
- Colourless urine
- Nausea and vomiting
- Headache due to pressure on the brain
- Changes in mental state (eg. confusion or disorientation)
- Drowsiness
- Muscle cramps
Don’t let this put you off drinking your daily dose, though.
You still need water to get rid of waste in your body, regulate your temperature, protect your joints and tissues – and you’ll be seriously dehydrated without it.
You can judge your own hydration levels by your urine colour – it ought to be a light yellow.
Urologist Dr Austin DeRosa told The Healthy that a possible sign you’re drinking more than your body needs is if you find yourself urinating more than 10 times a day.
Healthline recommends anyone who might be worried about over-hydration speaks to a doctor to get advice which is just right for them.
How much water do you need?
Estimates vary, with some experts recently debunking the claim you need to drink two litres a day. They suggested instead we should be aiming for 1.5 to 1.8 litres per day.
The US-based Mayo Clinic recommends sticking to the common rule of thumb that you need to drink eight glasses of water a day, while Healthline suggests drinking nine to 13 cups (between two and three litres) a day.
But this might need to change if you exercise, are in a difficult climate, are pregnant or breastfeeding, or you’re currently ill.
Healthline suggests: “The amount of water you need to drink can vary and should roughly equal the amount your kidneys release. Children and adolescents may have lower requirements than adults.”
This amount you need can also depend on your height, weight, age and health status.
About 20% of the liquid in your body comes from food (like fruit and vegetables) and the rest from drinks.
Don’t panic, though, if you don’t like water. Milk, juice, herbal teas, and even caffeinated drinks all count as fluids your body can use, too.