From a young age, we have been conditioned by the media, health professionals, and our schools to drink 8 glasses of water or two liters of water per day.
There may be plenty of contradictory health advice these days, but this is the one piece of health advice there seems to be a consensus on among medical professionals. If you read any article or advice column about losing weight, you can be guaranteed that there is a line somewhere that says;
‘To aid your body with fat or weight loss, be sure to drink plenty of water’
This is not entirely surprising, considering that water constitutes 60% of your body composition. So, there’s no doubt that drinking an adequate amount of water is crucial to maintaining a healthy diet.
However as with any health or diet advice, there isn’t a one-size-fits-all approach to water consumption.,
Personally, I have found the 2-litre or 8-glass water rule to be a bit excessive. Each of our biological makeup is different and as a result, we all have different nutritional needs. The amount of water that needs to be consumed depends on a variety of factors such as body weight and the rate that your body is losing water.
The importance of drinking an adequate amount of water
Along with protein, water is an essential building block in your body. In fact, it is the main chemical constituent in your body.
Water is an essential component of all cells, tissue and pretty much anything in our body. Here are some of the other crucial roles water plays in the body:
Metabolism and energy levels
Drinking an adequate amount of water ensures that your cells function as smoothly as possible. Water is crucial to metabolism, a series of chemical processes that convert stored chemical energy derived from food into energy needed for cellular processes in the body.
It’s so important that if your hydration drops by even 1%, that is enough to slow down metabolic processes significantly in the body. This is what is meant when people say that water ‘boosts’ energy. When metabolic processes slow down, you will feel drained of energy.
Low water levels can affect brain function
There are some studies that support the claim that reduced water intake or water loss affects people mentally.
One study showed that in a group of women, a 1.36% fluid loss following exercise increased the number of headaches, and worsened mood and concentration.[source 1, source 2]
Water is crucial in controlling body temperature
Through mechanisms like sweating, your body regulates temperature. Water ensures that the body doesn’t become overheated due to extreme weather or during intense physical exercise.
So, a reduced water intake can lead to poor body temperature regulation. As a result, there is a chance that poor water intake can hinder your physical performance.
The research on this is conflicted though. One study showed that among athletes, small changes in water consumption had little effect on their athletic performance. These studies were done on athletes and not regular people, so it’s hard to draw conclusions from that study.
Water helps with the elimination of toxins in the body
Your cells produce waste toxins all the time and these need to be eliminated properly. The body’s biggest toxin is blood urea nitrogen, a waste product that’s water-soluble.
It passes through the kidneys and eliminated through urine. Adequate consumption of water can help run this waste elimination process as smoothly as possible.
You’ll probably notice that on days that you don’t drink enough water, the urine will be darker, in lower quantity with a stronger odour. [source]
Water is important in healthy digestion
Sufficient water intake can help partially digested food move along in the digestive tract. Poor water intake can lead to digestive problems like constipation or irregular bowel movements.[source]
Signs that you aren’t getting enough water
You can tell if you’re not getting enough hydration when:
- You feel fatigued with frequent headaches
- Your physical performance is not up to its usual levels
- Your urine is dark, in small quantities and with a strong odour
- Your skin can appear dull, dry or wrinkled
- You have digestive issues like constipation
Factors that affect how much water you should drink daily
The rate of fluid loss
If you’re engaging in heavy physical exercise where you’re sweating a lot, you will obviously have to drink more water to replace the lost fluids. If you live in a hot climate, you will also need to drink more water as you will sweat more.
Fluid intake from food
If you consume a lot of fresh vegetables and fruit, you may need to consume less water. Our bodies can derive as much as 20% of the water intake from our food.
Salt intake
If you consume salty foods frequently, you will tend to feel thirstier and will need to consume more water. The increased water intake will be needed to flush out the extra sodium in the salt.
Body weight
If you have a small frame and have a lower body weight than the average person, you wouldn’t need to drink as much water as the average person. The 2-litre rule is for the average adult and doesn’t account for differences in body weight.
How much water should I drink then?
The best way to determine how much water you should drink is to experiment with different dosages and find the optimal amount.
The 2-litre rule is a good place to start. See how this level of water consumption affects your cognitive, digestive and physical performance.
If you’re getting too much water, your urine will be very light in colour. If you’re not getting enough you will experience some of the symptoms mentioned previously, and you should increase your daily water consumption.
The conclusion is that you need to listen to your body. Sometimes, people will confuse feelings of hunger and thirst. You may think you’re feeling hungry, but you’ll notice that drinking enough water will leave you feeling less ‘hungry’ throughout the day and as a result, it will prevent you from consuming too many calories too.[source]