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The Incredible Powers of Hydration

Hi everyone!

I’ve been meaning to write about this topic for awhile now, it is SO important. How many little “ailments” do you experience that can’t be improved by taking a few deeps breaths and drinking a nice tall glass of water?

I’m not claiming water is a miracle cure-all, but staying hydrated can help optimize our day-to-day functioning.

The Incredible Powers of Hydration

Here are a few of the incredible powers of hydration (and by a few I mean there are more than just what’s in this list!):

1) Attention + Alertness

Brain fog? Try drinking some water. Mild dehydration can cause impaired cognitive functioning. Studies have shown a decrease in concentration, alertness, and short-term memory due to mild dehydration in children + adults.

2) Energy

Fatigue is one of the most prolific ailments of American adults. Who isn’t tired? Fatigue is one of the symptoms of dehydration (fatigue is also a symptom of countless other health issues, so you may not be cured with H2O). Drinking a glass of water and taking a stretch break (getting some sunshine + movement with it is even better) is an easy, cheap first option to combating that afternoon slump.

3) Mood

Irritability + fatigue are two dehydration symptoms that often present together. Mood swings have been tied to dehydration, particularly in women. This may also coincide with headaches.

4) Hunger

You might think that thirst and hunger are entirely separate bodily indicators, but it turns out that we may be confusing them. Remember all the stuff about brain fog, fatigue, and crankiness? That could mean your body needs fuel, but if you’ve recently eaten a balanced meal, your body might just be in need of water, not food. Drinking a glass of water when hunger strikes between meals + snacks can be an effective tool for those trying to lose weight, too.

5) Cellular + Organ Function

The importance of hydration cannot be overstated, especially when it comes to overall body function and health. Even mild dehydration has been linked with chronic diseases. Your body just needs water to function properly, short and sweet.

We’ve all heard that our bodies are mostly water. The cells in our bodies are mostly water too (there’s not just a bunch of free water sloshing around inside of us). Down to the microscopic level, the amazing, tiny machinery in our bodies depend on water to carry out countless chemical reactions and help make up important compounds. The chemistry of water is absolutely fascinating.

The kidneys (control fluid balance)  and heart (master of pumping blood + helps control blood pressure) in particular are affected by dehydration. Your body works very hard to keep tight control on the volume and contents of your blood, and when you’re dehydrated, that can throw off the delicate balance. Staying hydrated helps your heart not have to work so hard.

I’m a dietitian, so I never pass up a chance to talk about the GI system. Water helps make up the necessary enzymatic secretions for the digestion process–like your saliva and gastric juice. Not to mention, dehydration is a major cause of constipation. Keep hydrated to keep regular! Note: as you increase fiber intake, likewise increase fluid intake to help keep things smooth.

6) Physical Performance

If athletes are just slightly dehydrated. their performance can suffer immensely. Hydration is no joke when it comes to sports + athletic performance. Check out the ACSM link below for specific hydration guidelines for the athlete.

So there you have it. Next time you’re feeling cranky, sluggish, dried out, hungry, or just plain BLAH, try taking a moment to yourself and drinking some cool, fresh water before reaching for a bottle of pills (or chocolate cake or a cigarette or whatever). Bonus if you can manage to get outside and get some fresh air and activity too!

How can you tell if you’re well-hydrated? It’s pretty simple–the urine test will do the trick. Lightly colored urine, and lots of it are a sign of good hydration status.

How much water should you be drinking? A rough rule of thumb is 1 mL / kcal. This means for every calorie you eat, you should be consuming 1 mL of fluid. For example, if you eat 2,000 calories, you should consume 2,000 mL, or 2 L of fluid each day. Children and adolescents need a bit more than this though. 

Remember that foods that contain water like all beverages (even coffee), soups, fruit, jell-o, and ice contribute to fluid intake.

Please beware that drinking too much water can cause serious health issues and be potentially fatal (i.e. your kidneys can’t excrete the water fast enough and it dilutes your blood). This sometime happens with athletes who are just trying to prevent dehydration and go wayyy overboard. A good rule of thumb is that when you’re training, weigh yourself before and after your workout. For every pound lost, you need to replace it with 20 fl oz of water.

Here is an awesome resource from the American College of Sports Medicine (ACSM) that provides specific guidelines for hydration before, during, and after exercise:
Selecting and Effectively Using Hydration for Fitness.

More resources:

Water & Nutrition from the CDC

Water: How Much Should You Drink Every Day? from Mayo Clinic

Staying Hydrated – Staying Healthy from American Heart Association

Popkin BM, D’Anci KE, Rosenberg IH. Water, Hydration and Health. Nutrition reviews. 2010;68(8):439-458. doi:10.1111/j.1753-4887.2010.00304.x.

Water Physiology: Essentiality, Metabolism, and Health Implications via Nutrition Today




Are you sold by the power of hydration? Share your thoughts in the comments to this post!


  1. […] Hydration has profound effects on how we function, both mentally and physically. In order to maintain focus + energy at work, we must stay hydrated. The easiest way to achieve this is to keep a container of fresh water at your work station at all times. For some people this is an easy habit, but for others, you may have to set alarms to remind yourself to drink up. […]