Hydration and the Brain (Part 1): How Water Affects Your Brain

3 Mins
Hydration and the Brain (Part 1): How Water Affects Your Brain

We all know water is important. We’ve all heard that we should drink at least eight 8-ounce glasses per day. But... why? Is water really that important. Yes! Find out why here...

  • Your body is at least 50% water.
  • Your brain is comprised of 75% water. That in and of itself should tell you how critical hydration is to the brain and body.
  • While we often think of food and nutrients as critical to life (they are), water is even more so. The average person can live only three to five days without water. Most can survive about three weeks without food.

Now that we’ve established water is important, let’s look at how it impacts you.

Hydration and Mood

When you are dehydrated, your brain actually shrinks in volume a bit. (It’s 75% water, remember?) This can cause a dehydration headache.

Dehydration also impacts your mood. In fact, one of the earliest signs of dehydration is grumpiness.

A 2013 study of 20 healthy women in their mid-20s were deprived of all beverages for 24 hours. After just 24 hours, all participants reported:

  • Moodiness
  • Fatigue
  • Confusion
  • Decreased alertness
  • Increased sleepiness

Within just 20 minutes of rehydrating, these effects began reversing.

Hydration and Cognition

Proper hydration can not only prevent headaches, it also prevents poor decisions. Dehydration impacts performance of the brain’s ability to process information, form new memories, and make correct decisions. It affects visual-spatial processing and other cognitive functions.

If you go into a business meeting dehydrated, chances are higher that you will feel that sluggish brain sensation. Your brain doesn’t have the balance of fluids to operate at full efficient capacity. When you have brain fog, you are slower to process data, and slower to act on that information.

Dehydration can also have a significant impact on performance activities, such as driving. Professor Ron Maughan at Loughborough University in the UK lead a study in 2015 to evaluate the impact of dehydrated driving. 

The study provided volunteers with 200ml of water on the hour the first day and had them complete a two-hour continuous driving simulator. The next day, the same simulation was repeated, but subjects were only given 25ml on the hour.

Professor Maughan found that the drivers made twice as many mistakes when dehydrated than when properly hydrated, including lane drifting, late braking and crossing the rumble strip.

“To put our results into perspective, the levels of driver error we found are of a similar magnitude to those found in people with a blood alcohol of .08%... in other words drivers who are not properly hydrated make the same number of errors as people who [drive intoxicated].”

Dehydrated driving is as dangerous as driving under the influence of drugs or alcohol.

Dehydration and Performance

Whether you are running, playing tennis, baseball, basketball or weightlifting, whether you are participating in team or individual activities, your hydration level impacts your performance. Having sufficient water in the body improves your reaction time and equilibrium (balance). 

A two percent level of dehydration leads to a 10 percent drop in athletic performance. And as you exercise, hydration is compromised. It’s especially important to stay hydrated as you exercise. In addition, dehydration slows your metabolism.

Hydration Matters.

Hydration matters to every aspect of brain and body. Using a tool like the Vortex Mixer Bottle can make hydration even easier and tastier to hydrate. (You can also incorporate vitamins and brain boosting supplements in your water.) Want to start staying hydrated throughout the day? Stay tuned for Part II on Hydration and the Brain, which will include some pointers to help you change your habits!

Read Part Two