Benefits of staying hydrated: why it could help you age healthily

A simple glass of water could be key to keeping you on top form.

The human body is made up of 55% to 70% water, depending on your age. So it’s not surprising that drinking enough and staying hydrated is crucial to keep your body functioning at its best.  

And as we age, this could be more important than ever for helping us to live a longer and healthier life.  Results from a recent study suggest that people who are sufficiently hydrated may be less likely to develop chronic illnesses or show signs of ageing.

Woman in a yellow waterproof coat drinking from a matching coloured bottle to ensure she is staying hydrated during her walk.Credit: Shutterstock/DisobeyArt

Researchers analysed sodium levels in the blood of 15,700 adults, aged 45-66, for 25 years. Drinking water is important for maintaining normal sodium levels, so the amount of sodium in someone’s blood can be used to measure how hydrated they are. 

Findings showed that people who had the higher end of a normal range of sodium in their blood had a 39% greater chance of developing chronic illnesses. They were also 50% more likely to have biological markers of age older than their chronological age. Chronological age is the number of years you’ve been alive, while biological age refers to the physical age of your cells and tissues. 

Lesley Carter, a registered nurse and programme lead at the Malnutrition Task Force, which is supported by Age UK, agrees. She explains that not having enough fluid can cause an imbalance of electrolytes, such as sodium, which can affect your overall health. “Drink around six to eight glasses or 1.5 litres of fluid per day,” she says. Your fluid needs can vary and depend on a variety of factors, including your age, lifestyle, body size and climate. 

Authors of the study did note the need for more studies to confirm the link between hydration and ageing. 


Our top tip for staying hydrated 

Download a water tracking app to keep tabs on how much you’re drinking. Water Tracker – Water Reminder is available on Android and Water Tracker – Drink Reminder is available on Apple devices. 

Benefits of staying hydrated – and what counts

Person's hand holding a glass being filled with water from a tap, with sun beams shining down on it.Credit: Exceptional
Staying hydrated can help to reduce sleep disturbances.

Staying hydrated can provide many benefits for your health.  

  • It can help prevent urinary tract infections – by diluting your urine and ensuring you pee often. This allows bacteria to be flushed from your urinary tract before an infection can begin 
  • It can ease constipation – drinking enough helps to keep stools soft and makes them move through the bowel and pass more easily. Carter explains this is especially important for people on certain medications that can contribute to constipation. 
  • Research shows increasing water intake can reduce or prevent headache pain. 
  • Boost cognitive function and mood – studies show that drinking water can have positive effects, particularly by maintaining visual attention and increasing alertness. 
  • Better breathing – Carter says drinking enough fluids means your blood will be well oxygenated, which will help you to breathe well.  
  • It can improve sleep – there is increasing research into the link between hydration and sleep. According to the Sleep Foundation, staying hydrated can reduce sleep disturbances. 

Carter says: “Fluid is not just about water. If you don’t like water and the thought of drinking eight cups is beyond you, you could have soup or custard.” She also suggests a cup of tea or coffee, or a stew with gravy, as alternatives. 

“Make it work for you. Have things that you enjoy and you can manage.” 

Hydration FAQs

While there is no need to panic, it’s important to be aware that not drinking enough can lead to serious consequences for your health. 

Carter says that it can take just two days for an older frail person to show lots of signs and symptoms associated with becoming really dehydrated. 

  • Feeling dizzy or lightheaded – “If you’re older and feel dizzy as you get up, you could find yourself on the floor and break a bone,” says Carter. 
  • Dry mouth, lips, tongue or skin – if you have dry skin and catch yourself somewhere, Carter says, it could make it bleed and lead to complications, such as an ulcer. 
  • Thirst – feeling thirsty can be the brain’s way of telling you that you need to drink more, according to NHS Scotland 
  • Dark yellow, strong-smelling pee – your urine is a good indicator as to whether you’re hydrated. The NHS urine chart can help you to check the colour of your pee to see whether you’re drinking enough. 
  • Peeing less often than usual can be a cause of dehydration. Your kidneys try to keep as much urine as possible to combat this. 

Drinking fluids regularly throughout the day, aiming for at least six to eight glasses. Having a glass when you first wake up and before each meal can be a good way to help with this.

Carter provides support on how you can do this, whatever your lifestyle or age. 

  • Make drinking water a habit – remind yourself to drink, says Carter, for example by drinking a glass every time you sit down to watch your favourite TV programme. 
  • Take a bottle of water with you when you go out – there are lots of bottles small enough to fit in your bag. Here are a few options from Amazon. 
  • Limit caffeine before bed – “If you’re worried about peeing too much during the night, there’s no need to reduce the amount of fluid you’re drinking. Instead, cut out caffeine later in the day.” She also suggests avoiding alcohol in the evening. Alcoholic drinks or drinks containing caffeine can cause your kidneys to produce more urine. 
  • Eat hydrating foods, such as watermelons, oranges and cucumbers. 
  • Little and often is okay – “If the thought of having a big glass is too much, spread it out over an hour. Every 15 minutes, drink a quarter of a cup.” 

Research has suggested that milk could be a better hydration fluid than water. However, experts say these studies have limitations, such as small numbers of participants and unreliable ways of measuring hydration. Milk does contain calories, which is worth bearing in mind if you’re trying to control your weight. More research is needed to confirm whether milk rehydrates better. Meanwhile, tap water is cost-free and calorie-free. Carter says drinking water isn’t the sole solution to staying hydrated and that any fluid counts. 

Why some people struggle to stay hydrated

Older woman trying to stay hydrated by drinking water from a glass.Credit: Shutterstock/JLCo Ana Suanes
Staying hydrated can be a challenge as you age because you might not feel as thirsty.

Some older people or those with chronic illnesses, such as dementia, can experience issues with drinking enough fluid. 

Carter says: “As you age, you don’t necessarily feel as thirsty or the need to drink as much as you did when you were younger. 

“Some people don’t realise how important being hydrated is.”  

Another issue, she says, is that those with a weak bladder may worry about being incontinent and choose not to drink so much because of that. But Carter explains the idea that reducing fluid intake will reduce the amount you’re peeing is a myth. 

“When you drink less, your kidneys overact, and this can make you pee even more.” 

Carter says people with dementia may have forgotten that they haven’t had a drink or that they need to drink throughout the day. “If they’re living alone and they haven’t got any reminders, they won’t drink.” 

Carter’s top hydration tips for older people or those with chronic illnesses 

  • Use a straw – “Some people’s throats can get a bit restricted, so they find it difficult to swallow large mouthfuls. Sucking the fluid through a straw helps it trickle down more easily,” says Carter. 
  • Create drinking prompts if you or someone you know has dementia – Carter suggests placing a sticky label, with a reminder to drink on it, above the tap or on the cupboard, or setting a phone alarm. 
  • Make sure fluids are easily accessible – she says if you or someone you know is less able, make sure that a drink is available and within reach. 

Alzheimer’s Society has more tips on supporting a person with dementia to drink enough. 

Carter’s top takeaway? Get your equivalent of six to eight glasses of fluid per day. “If you don’t reach eight glasses one day, don’t beat yourself up. Start again tomorrow.” 

The Malnutrition Task Force has more advice on managing hydration 

Lesley Carter is a registered nurse and clinical lead for Age UK. She works in Health Influencing and leads Professionals and Practice and the Malnutrition Task Force. Previously, she worked within the Department of Health as the London Lead for the development and implementation of the National Dementia Strategy. 

Gemma Harris

Written by Gemma Harris she/her


Gemma Harris has been a journalist for over seven years and is a self-confessed health and wellbeing enthusiast, which led her to specialise in health journalism. During her career, she has worked with top editors in the industry and taken on multiple high-discipline fitness challenges for certain outlets. She is particularly passionate about nutrition; after being diagnosed with irritable bowel syndrome in 2016, she discovered her fascination for gut health and founded – a dedicated space for providing a hopeful outcome for people with gut issues. Gemma’s core aim is to help others through her writing.

  • instagram
  • linkedin