Why Hydration is Important

The Role Of Water In Adults 

Water as a compound (H²O) makes up around 40-62% of the human body (Perrier et al., 2021).

Thereby, it only makes sense that its consumption is vital in sustaining a healthy life, where its absence can even have lethal effects within days (Perrier et al., 2021).  

Within this blog, we will highlight arguably 5 of the most important roles of water in the human body. 

#1 Transportation of nutrients and oxygen 

Water promotes the transportation of nutrients and oxygen through the capillaries in the intestines. The nutrients are then directed towards the blood and circulatory system to nourish vital tissues and organs. 

#2 Regulating Core Body Temperature

Water regulates the body’s temperature by reducing heat and sweating. Dehydration increases the risk of hyperthermia and heatstroke. 

#3 Aiding the Digestive System

Water helps decompose food in the stomach and softens the stool. 

#4 Protecting Organs 

Water helps remove toxins from the liver and supports the functions of the kidneys, thereby placing less burden on these organs and lowering the risk of damage. 

#5 Lubricating joints 

A liquid substance called synovial fluid lubricates joints and reduces friction.  Synovial fluid is primarily made up of water, so it’s important to stay hydrated to maintain healthy lubricated joints. (Perrier et al., 2021)

How Much Water Do Adults Need? 

Water requirements can vary depending on the days that you exercise. 

#1 Sedentary 

According to the British Dietetic Association, an adult male should have at least a net water intake of around 2L (8 glasses) per day and a female adult should consume around 1.6L (6 glasses) per day.

#2 Exercising 

People who exercise would need more water as 1-2% of the bodyweight is excreted through heat/sweat. So it’s important to top up with an additional 500-1L of water. (BDA, 2020)

The Importance Of Hydration In Later Life 

Maintaining a good hydration status is especially important for older adults.

Certain variables put them at risk of dehydration, like increased fluid loss and decrease intake from a lower sense of thirst (Heung et al., 2021).

Although older adults are more prone to the effects of dehydration, the recommended daily allowance remains the same throughout the adult life span (BDA, 2020).

Here are 3 of the most detrimental risk factors of dehydration amongst older adults. 

#1 Kidney Health 

The kidneys are two bean-shaped organs located towards the lower back. Their main function is to filter out the waste products from the blood and excrete it through the urine. 

Moreover, they help maintain fluid and electrolyte balance in the body. You could expect a decline in these kidney functions in older adults. 

For this reason, it’s important to stay well hydrated as this will put a lesser burden on the kidneys to remove the waste, and in turn, may help maintain kidney functions.

#2 Brain Health 

If the brain cells become dehydrated, cognitive functions and coordination could become impaired. In older adults, this can also mimic dementia. 

Just another reason why older adults need to stay hydrated. 

#3 Urinary Tract Infection

Another effect of dehydration amongst seniors is UTI, which can lead to many complications such as confusion and falls, followed by subsequent blunt force injuries.  (Heung et al., 2021)

The Importance Of Hydration In Prenatal Women 

Prenatal women are more likely to become dehydrated due to morning sickness so they must not forget to top up the water. 

According to the British Dietetic Association, an additional 300ml of water is recommended to prenatal women or simply 1 additional glass. So we’re looking at a total of 1.9L of water intake per day.

Let’s highlight two important reasons for prenatal women to maintain sufficient hydration. 

#1 Forming Amniotic Fluid 

Water is an essential component in forming the amniotic fluid surrounding a baby in the womb.

#2 Importance for blood volumes

Water promotes adequate blood volume and helps form the baby’s tissues. (BDA, 2020)

The Importance Of Hydration In Postnatal Women

Postnatal women require more water than prenatal women. 

It’s recommended to get an additional 6-700ml of water (2 glasses) equating to a total of 2.2-2.3L daily. The reason for this is that postnatal women often lactate, which decreases hydration levels. (BDA, 2020)

How To Boost Water Consumption?

Other than drinking water directly, hydration status can be maintained by consuming water-dense foods like; 

  • Fruit
  • Vegetables
  • Prepared soups 
  • Prepared oats
  • Juices
  • Teas 
  • Coffees
  • Carbonated beverages (BDA, 2020)


Water intake is one of the most important nutritional interventions to maintain good health.  

The recommended intake is 1.6L for women and 2L for men of all ages.

Older adults are more prone to the negative effects of dehydration, including; decreased kidney health, decreased brain health and increased risk of UTI. 

Water intake differentiates between pre and postnatal women due to morning sickness and lactating. 

Prenatal women are recommended +300ml and postnatal women are recommended +600-700ml from the 1.6L for adult women. 

Water intake is not limited to a glass of water, you can also stay hydrated with foods with high water content like; fruit, vegetables and soups. 


British Dietetics Association (2020). Fluid (Water and Drinks): food fact sheet [Online]. Available from: https://www.bda.uk.com/resource/fluid-water-drinks.html [Accessed 25 February 2022] 

Heung, V., NG, T., Yee, T., et al. (2021). ‘Understanding Dehydration in the Elderly’  Centre Aging and Healthcare Management and Research  1(1): 1-10 

Perrier, E.T., Armstrong, E.T., Peronnet, F., et al. (2021). Hydration for health hypothesis: a narrative review of supporting evidence. European Journal of Nutrition 60(1): 1167-1180

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