Stay hydrated! Forget the myths and stick with these tips
THE old adage of drinking at least eight glasses of water a day is out the door. Instead, an expert advises we should consume as much as our body needs.
Nephrologist and Transplant Physician at St Vincent's Hospital Melbourne and Deakin University School of Medicine deputy head, Professor Karen Dwyer, said there are many variables to consider when determining just how much water we need each day to quell our thirst and keep us healthy.
"Your body is finely tuned to regulate your fluid and you need to respond to the cues that your body initiates," Professor Dwyer said.
Some of those variables are age, weight, gender, amount of activity, the climate where you live in and the presence of one or more diseases or disorders.
People with health problems such as chronic liver disease, cardiac disease or diarrheal issues - all need to have their fluid intake considered on an individual basis.
The cues for needing to drink more can be you feel thirsty or a bit dizzy, or have a headache, you are hardly going to the toilet during the day or your urine is dark yellow. The cues for drinking less may be that you are running to the toilet many times during the day or your urine is clear or light colour.
"It's responding to your cues and looking at what your body is trying to tell you," Professor Dwyer said.
When working out how much water your body needs, don't forget to consider all the different forms water comes in - tea, coffee, and through rice and pasta, fruit and vegetables, for example. While the base amount of water you need each day is probably around two litres, while consuming these drinks and foods you are taking in a lot of that recommended fluid amount.
Water will always be the first and prime recommendation. However, "A cup of coffee or tea is still a significant amount of fluid that is being replaced," Professor Dwyer said. "And yes, you will wee some of that out due to the mild diuretic effect. You are unlikely to become dehydrated just by drinking coffee, for example."
Why drink water?
Since 60 per cent of our lean body mass is made up of water, it's a very important to our body's functions. When you become dehydrated you will lose fluid initially from outside the cells, but eventually the cells will also lose fluid and that's when your body stops working properly.
Our kidneys keep busy
The kidneys regulate the salt content in our blood. "If you reduce your fluid intake, the kidneys will concentrate and not wee out so much fluid so that you maintain this concentration in the blood," Professor Dwyers said. "If you take a heap of fluid in, it's going to wee it out."
Can you drink too much?
For the average person it's reasonably safe to drink as much water as you like during the day. "The kidney is quite a sophisticated organ and has a high regulatory capacity so that it varies your output according to your intake," Professor Dwyer said.
"We lose fluid through sweat, our lungs and bowel, but that is probably a minimal amount unless we are in a really hot climate and we are doing a lot of exercise. On a day-to-day basis, our fluid balance is regulated by our kidneys. If you drink a heap, you are going to week a heap out."
Knowing when to drink?
It's particularly important to remain aware of the hydration needs of people with dementia whose perception of what they need and what is affected by their cognitive decline.
"For people with comorbidities there may need to be some encouragement to ensure that they are drinking, and thinking about things like constipation which may be a symptom that they are not drinking enough fluids," Professor Dwyer said.
"The body's cues will change with time and they become subtler as someone ages which is consistent of the ageing body."