Some years ago, Kidney Health Australia (KHA) put out a position statement on water. The statement, called ‘Drink Water Instead’, highlighted the importance of water in maintaining kidney health. This is because without adequate water, our kidneys suffer and cannot properly function.
What is the function of the kidneys?
The kidneys perform a role that is rather like a very efficient waste disposal unit. Without kidney function, we would die within a matter of days – which is clearly why we have two of them! Even if one fails, the other one can continue the job as long as it is healthy.
The main role of the kidneys is to filter out and collect waste materials – such as unwanted chemicals, excess fluid and unneeded nutrients – and combine them with water to create urine for elimination via the bladder. This filtering process can happen hundreds of times a day and yet most of us probably never give it a second thought – that is until we develop an uncomfortable problem such as a kidney stone, or a urinary tract infection!
The kidneys also have a number of other roles, including balancing the volume of minerals and fluids in the body, and producing hormones and enzymes that make red blood cells and are involved in the control of blood pressure and maintenance of bone health.
Looking after our kidneys
We tend to hear a lot about looking after our heart health and taking care of our skin and bones, but not much about the kidneys – even though our lives depend upon them!
Keeping well hydrated is essential, especially as between two and three litres of water is lost every day through elimination and also through the skin and lungs. Water is considered preferable to sugar-based drinks, as the latter may affect dental health and are also associated with Chronic Kidney Disease (CKD) when taken to excess.
How much water should we drink?
As long as we are generally healthy, there are no set rules about how much water we should drink. It depends upon a number of factors such as environment and lifestyle. For instance, if someone lives in a tropical region, or does strenuous work or exercise, their fluid needs are going to be higher than those of someone living in a more temperate zone with a sedentary occupation.
At one time it was stated that all adults should drink at least two litres of water per day. However, the KHA position is that we should drink according to thirst, and that caffeinated and sugared drinks should be limited. There are some exceptions to this – for instance if someone has had a kidney stone, it is recommended that they drink at least two litres per day to reduce the risk of another one.
People with certain health conditions – including end-stage renal failure – may need to reduce their fluid intake in accordance with their doctor’s advice.
As well as getting adequate water each day, maintaining a healthy lifestyle through diet and exercise and quitting smoking if necessary can also help keep the kidneys in good health. Alcohol should be limited as it has a dehydrating effect on the body, and reducing salt may help to lower the risk of kidney stones.
If you suffer from kidney stones you should see your doctor or a kidney stone specialist to discuss treatments such as kidney stone removal and measures to reduce your risk level.