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Water on the Brain

It is no secret that drinking plenty of water is great for your body, but does it do anything for your decision performance? Boy, does it.

If you want your decision making engine - your brain - to be as effective as possible, it needs big doses of these four ingredients: sleep, exercise, healthy diet, and the subject of this article - the elixir of life - water. And since water actually enhances how well your body responds to the other three ingredients, let’s dive right in!

We naturally crave water since it makes up 50-70% of our bodies. Sadly, 29% of the world population do not have access to safe drinking water. Those of us that do need to appreciate our good fortune and take advantage of it.

I was never a huge water drinker myself until a blood lab report showed that my kidneys were not functioning as well as they should be. My doctor recommended 2 things: 1) reduce salt intake, 2) increase hydration. I took her advice to heart (and kidney!).

The physical benefits of increased hydration not only include improved kidney function but it has helped with my weight loss goals as well. Water improves metabolism and digestion and increases satiation, making me feel less hungry.

While those are awesome benefits, I had no idea how much my brain would benefit as well.

Brain boost

These brain functions are essential to effective thinking and decision making:

- memory

- focus and attention

- information processing speed

As many studies have shown, dehydration can adversely affect each of those.

In one study by Dr. Caroline Edmonds of the University of East London School of Psychology and her team, subjects who drank water before a cognitive test had 14% better reaction time and reported feeling less confused and tense than those who did not drink water.

An analysis of 33 studies with over 400 participants found that dehydration was associated with significant impairments on attention, executive function, and motor coordination.

Another study showed that increasing daily H2O intake by just a few glasses per day can lead to positive emotional changes and increased energy.

Get your water

How much do we need? The commonly cited “8 glasses (8 oz.) a day” rule does not appear to have scientific backing and the amount needed varies by a number of factors, from where you live to your activity level and the time of year. However, 8x8 is easy to remember so if it helps you remember to drink more water, great.

The U.S. National Academies of Sciences, Engineering, and Medicine says that in general men need about 125 ounces of fluid daily and women about 91 ounces. That includes other sources of fluids besides water, primarily other beverages and food.

Some of the best water rich foods include melon, oranges, berries, lettuce, and cucumbers.

If you are looking to burn calories, ice cold water burns about 8 calories more per glass than room temperature water. It’s a small benefit but could be helpful depending on how much you drink.

A good rule of thumb is to watch your urine color. Notice how often you are thirsty.

I start every day with about 20 ounces of water. Since I don’t eat until mid-day, that fluid intake helps me stave off hunger and avoid temptation until lunchtime.

So cheers to water - drink up!

- Steve Haffner

Want to learn more about improving your decision performance?

Click here for my free book, 7 Strategies for Making Better Decisions


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