The human body is made up of 50-75% water and cannot survive without water more than a few days. Water forms the basis of blood, digestive juices, urine and perspiration, and is contained in lean muscle, fat and bones. Babies and the elderly are vulnerable to lack of water or dehydration. Not drinking enough water increases the risk of kidney stones and, in women, urinary tract infections.
Importance of water:
Water is needed for most body functions, including to:
- maintain the health and integrity of every cell in the body
- keep the bloodstream liquid enough to flow through blood vessels
- help eliminate the byproducts of the body’s metabolism, excess electrolytes (for example, sodium and potassium), and urea, which is a waste product formed through the processing of dietary protein
- regulate body temperature through sweating
- moisten mucous membranes such as those of the lungs and mouth
- lubricate and cushion joints
- reduce the risk of cystitis by keeping the bladder clear of bacteria
- aid digestion and prevent constipation
- moisturise the skin to maintain its texture and appearance
- carry nutrients and oxygen to cells
- serve as a shock absorber inside the eyes, spinal cord and in the amniotic sac surrounding the fetus in pregnancy.
So how much Water does the body need?
The biggest problem is that our bodies cannot store water so we need to replenish the water stores with fresh supplies every day to make up for losses from the lungs, skin, urine and faeces. Traditional knowledge suggests that eight to ten eight-ounce glasses of water (over half a gallon of water) need to be consumed by humans every day. Many diet experts proclaim that the US population is highly dehydrated and face a lot of health issues due to poor water intake. Are we at risk if we do not abide by the “recommended” intake figures?
Well, the general rule is your body needs to replenish the water it has lost, which is about 2.5 to 3 litres (85 to 100 Oz) a day. So replenishing this water store is critical to maintain the balance. The general rule is if you are thirsty, drink water. But most of us, due to our hectic lifestyle and stress, fail to understand our body signals and drink lesser and later than the body needs. The amount we need depends on our body size, metabolism, the weather, the food we eat and our activity levels.
Who needs more fluids?
People need more than the recommended dose if they are:
- on a high-protein diet
- on a high-fibre diet, as fluids help prevent constipation
- pregnant or breastfeeding (the fluid need is 750-1,000 ml a day above basic needs)
- vomiting or have diarrhoea
- physically active
- exposed to warm or hot conditions.
An interesting video titled “How Much Water Do We Really Need to Drink?” gives a frank perspective on how you can understand how much water you actually need.