• Ryan C. Warner, Ph.D., CRC

Drinking Water May Improve Your Decision Making

Updated: Jan 18, 2021

Dr. Ryan C. Warner Blog Post

So what can we do to make better decisions in life? For answers, one place we can look is to the world around us. The most vast and essential compound on this planet is water. It is no secret that all living organisms require water for survival. The human body is made up of around 70 percent water, and drinking enough safe water daily helps boost our physical and mental health. Did you know it can also contribute to improved decision making?

For instance, in a recent study adult participants took tests on their cognitive performance after having fasted from the night before. Those who drank 500ml of water before testing later demonstrated improved performance on tasks measuring cognitive reflection in judgment and decision making. Additionally, in subjects between the ages of 18 and 30, experts found that drinking water improved memory and focus.

Improper Hydration

There are many adverse impacts improper hydration may have. For instance, over-hydration can cause the electrolyte levels in the body to become unbalanced and cause sodium levels to drop dramatically. Without sodium, your brain cannot initiate the electrical impulses your nerve cells require for proper communication. Without proper communication, decision making and judgement will be impaired.

Although over-hydration can be harmful, nearly 80 percent of individuals report that they don't drink enough water. One impact mild dehydration may have is the possible suppression of blood flow to the brain. Having proper blood flow to your brain is important for healthy cognitive function. Circulating blood supplies your brain with the oxygen and essential nutrients it needs to function properly. Furthermore, dehydration has been shown to increase the release of the stress hormone cortisol. Elevated cortisol levels have been associated with impaired cognitive function and decision-making difficulties. For instance, a 2018 study randomly assigned 56 participants to a social stressor. Participants in the stress condition responded with higher heart rates, reported more negative moods, and on the decision-making task made less advantageous choices. Ultimately, adequate hydration may assist with peak cognitive performance.

Sipping Towards a Better You