Our bodies are around 60% water, give or take.
It is commonly recommended to drink eight 8-ounce glasses of water per day (the 8×8 rule).
Although there is little science behind this specific rule, staying hydrated is important.
Here are evidence-based health benefits of drinking plenty of water.
Water Helps to Maximize Physical Performance
Dehydration can have a noticeable effect if you lose as little as 2% of your body’s water content. However, it is not uncommon for athletes to lose up to 6-10% of their water weight via sweat.
This can lead to altered body temperature control, reduced motivation, increased fatigue and make exercise feel much more difficult, both physically and mentally.
Optimal hydration has been shown to prevent this from happening, and may even reduce the oxidative stress that occurs during high intensity exercise. This is not surprising when you consider that muscle is about 80% water.
Hydration Has a Major Effect on Energy Levels and Brain Function
Your brain is strongly influenced by hydration status.
Studies show that even mild dehydration (1-3% of body weight) can impair many aspects of brain function.
Drinking Water May Help to Prevent and Treat Headaches
Dehydration can trigger headaches and migraines in some individuals.
Several studies have shown that water can relieve headaches in those who are dehydrated.
Drinking water can sometimes help relieve headache symptoms, especially in people who are dehydrated.
Drinking More Water May Help Relieve Constipation
Constipation is a common problem, characterized by infrequent bowel movements and difficulty passing stool.
Increasing fluid intake is often recommended as a part of the treatment protocol, and there is some evidence to back this up.
Drinking Water May Help Treat Kidney Stones
Higher fluid intake increases the volume of urine passing through the kidneys, which dilutes the concentration of minerals, so they are less likely to crystallize and form clumps.
Water may also help prevent the initial formation of stones, but studies are required to confirm this.
Drinking More Water Can Help With Weight Loss
Drinking plenty of water can help you lose weight.
This is due to the fact that water can increase satiety and boost your metabolic rate.
In two studies, drinking half a liter (17 ounces) of water was shown to increase metabolism by 24-30% for up to 1.5 hours.
This means that drinking 2 liters of water every day can increase your total energy expenditure by up to 96 calories per day.