Many good students rush to private tutors after school and are unwilling to rest at night, but their test scores are still not as good as expected. This is because they ignore the most basic elements for the brain to function. Besides sleep, another thing that is often overlooked is hydration. From 2009 to 2012, a study in the United States investigated whether 4,000 children and adolescents aged 6 to 19 drank enough water. The study measured the concentration of their urine and found that more than half of them did not drink enough water, especially boys.
Over 75% of the brain is water, so to keep the mind active, enough water must be absorbed. In 2012, the Journal of the American College of Nutrition published an article that explored the relationship between insufficient water in the body and cognitive ability. It turns out that losing even 2% of your body weight in water is enough to significantly reduce cognitive abilities. The three most impaired cognitive abilities are precisely the ones that are crucial to test performance: 1. Attention; 2. Psychomotor skills; 3. Immediate memory.
For example, during the entire listening test, our attention function allows us to focus 100% on the test questions and shut out the background noise in the classroom; psychomotor skills enable us to write down what we hear quickly and accurately; and immediate memory allows us to remember a conversation of more than ten seconds in our mind, and then answer a question regarding that conversation. This shows that dehydration is detrimental to the whole academic endeavor, especially when taking exams.
According to the Centre for Health Protection, each person should drink at least 6 to 8 glasses of fluids (each glass is about 240 ml) every day, and more under hot weather. However, please note that it is better to drink less sugary drinks. How can we remember to drink enough water but not too much amid our busy schedule? The answer is to establish a daily water-drinking rhythm. For example, drink a glass of water for breakfast, bring a 500 ml water bottle to school, and drink up the water in the bottle across two separate moments in the morning; at lunch, refill the bottle and drink it up before school is over; after getting home, drink yet another glass of water.
Written by: Dr. William Chui
Originally posted on: HKEJ Health
Translated by: Cheuk Long Chan
