The importance of drinking enough water has been widely documented. Our body is composed of 60% water and due to normal bodily functioning and exercise, we are constantly losing water that needs to be replenished. The human body can only survive a few days in the absence of water. We all know the basic components of hydration, but do we know the importance of proper hydration: how much water should I drink?
The commonly quoted recommended intake is 8 glasses of water per day (or the 8 x 8 rule) is often challenged, where did this value even come from? Is it even an accurate rule or just an arbitrary number? How about tea and coffee – do these contribute to water intake? Also, can you drink water to lose weight? Before we resort to our historical bro-science knowledge to demystify these queries, let’s see what the research says.
Importance of hydration – health
Water is considered a miracle nutrient that aids in general health and well-being. Adequate hydration promotes healthy functioning of organs, especially the kidneys; dermatologists and skin care professionals constantly advocate the importance of hydration for skin. Hypohydration is linked with many adverse effects, including a decline in mental performance, increased risk of chronic diseases such as hyperglycemia – diabetes, heart disease and strokes. It can also lead to confusion as the body feels hunger when in fact the body is thirsty.
Benefits of proper hydration include:
- Helps produce saliva
- Assists in digestion of food
- Assists in weight loss
- Aids in regulating food cravings
- Prevents constipation
- Helps boost energy levels
- Helps improve mood
Importance of hydration – exercise
Proper hydration is a fundamental requirement to achieving peak performance during a workout. During exercise, fluid is lost through the processes of sweating, excretion and breathing. Generally, athletes underestimate their fluid loss and so fail to adequately rehydrate during exercise to replenish lost fluids. Even minimal dehydration is linked to reduced performance. It can affect power, strength and endurance.
Mental and physical decline have also been documented as adverse effects of suboptimal hydration. Research has demonstrated that a reduction in water (equivalent to 2% body weight) exerts increased pressure on the heart and exacerbates how difficult a workout feels, particularly during activities in hot environments. Depending on intensity, climate and personal factors, water loss during exercise can range anywhere from 750ml – 2L per hour. Dehydration is something which the body can never be trained to acclimatise to and so efforts should be taken to replenish lost fluids; for some athletes, this means replenishing lost electrolytes too. Rehydrating during exercise helps prevent the risk of heat stress, performance decline and fatigue.
Am I drinking enough water?
Achieving the correct balance of drinking enough water can be difficult to conquer. The effects of not drinking enough water are evident from the previous paragraphs. However, the signs you’re not drinking enough water can be somewhat difficult to pinpoint as they could be attributed to other factors. Some of the signs of dehydration in adults and children include:
- Dark coloured urine
- Feelings of thirst
- Feelings of hunger
- Less frequent urination, <4 times per day
Unfortunately, merely prescribing an 8 glasses of water per day quota is not an accurate representation of what each individual needs to adequately hydrate.
The National Academies of Sciences, Engineering, and Medicine identified the below as adequate daily fluid intake targets:
Men: About 15.5 cups (3.7 litres) of fluids
Women: About 11.5 cups (2.7 litres) of fluids
However, each individual has personal and environmental considerations which can alter their requirements. These include:
- Body size
- Personal sweat rate
- Personal health conditions, e.g. diarrhoea/constipation
- Work activity level
- Exercise duration and intensity
- Environmental temperature
Ok, so you’re thinking that still hasn’t answered your question? Let me offer you two simple methods of estimating hydration levels, both of which have no cost and are simple to interpret!
Our bodies are primed with various organs and systems to enable survival. As such, since water is such a fundamental requirement to live and since it constitutes such a huge proportion of our body, it makes sense that each person is fitted with a regulator to aid in maintaining water balance. The simple rule is that if you feel thirsty, drink (preferably water) until your don’t feel thirsty anymore.
2. Urine colour
The colour of your urine can help determine if you’re consuming sufficient fluids. You should aim to have light yellow or clear urine. The more concentrated the colour, the more dehydrated you’re likely to be. If it’s a dark colour, you probably need to drink up!
Warning: Caveat – proceed with caution!
While thirst is an indicator that you may need to consume fluid, relying solely on thirst can be a poor indicator of when liquid should be replenished. Thirst regulation can be affected as people age, so elderly people may need to remind themselves to rehydrate. Additionally, athletes and personnel engaging in strenuous work/exercise and sweat may need to replenish lost fluids sooner.
Drinking water before, during and after exercise helps
ensure optimal hydration levels are maintained
All this being said, it’s worth considering that hyperhydration is also the other end of the spectrum and is linked with adverse effects. Want me to do an article on excess water consumption or other fluid-related topics? Comment below!
Do other drinks count towards water intake?
Contrary to popular belief and misleading information, caffeinated drinks and even some beers may count towards your daily water intake. That said, a diet composed primarily of fizzy drinks, alcohol and caffeinated beverages isn’t recommended. Water should be the fluid of choice before opting for teas and coffees. In addition to these, many foods also contain water, e.g. watermelon, tomatoes, apples, broccoli all contain upwards of 80% natural water content. Other foods that also contribute to water intake include meat, fish and eggs. So before you go chugging gallons of water on top of you copious cups of tea, take into consideration the different foods and drinks consumed throughout the day that can add to your daily water targets.
So now you know how to hydrate your body optimally, why not learn how to eat healthily too and find out the Top 5 healthy & unhealthy eating habits – are you guilty of them?
- Fluid intake differs between individuals, there is no single formula for recommended daily water intake.
- The 8 x 8 rule may be a good target to aim for, but it’s not necessarily an accurate reflection of water intake requirements.
- Urine colour and thirst levels are good indicators of hydration levels.
- Drink when you’re thirsty, stop drinking when your thirst is quenched.
- If you’re sweating a lot, or working in a hot area, extra efforts should be taken to rehydrate frequently.
- Besides water, caffeinated drinks and food also contribute to daily hydration and should be accounted for.
- While caffeinated drinks do contribute to total water intake, aim to make water your go-to drink.
What are you still doing here? Go grab some water!
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