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One Major Side Effect of Not Drinking Enough Water, Says Study

If you’re not one to drink water throughout the day, you may be experiencing this.

If you've spent any time on social media, it's highly likely you've come across some kind of health or fitness buff who is preaching to you how important it is to be drinking enough water throughout the day. And while we know our bodies need water to properly function and survive, the truth is, if you're not drinking enough water during the day, there is one serious side effect you need to be aware of—and that's how water can affect your mood.

It's true, the science is there. Drinking water is scientifically linked to help you feel awake, keep you alert, and even keep you in high spirits, according to a study from PLOS One. Here's how, and for even more healthy tips, be sure to check out our list of The 7 Healthiest Foods to Eat Right Now.

Not drinking water will put you in a bad mood.

In the specific study by PLOS One, researchers evaluated what happened when they asked two different groups to drink different amounts of water. The first group represented high-volume water drinkers, who were asked to decrease their usual amount every day. The second group represented low-volume water drinkers, who were asked to increase their usual amount.

The results of the study showed that mood was significantly affected based on water intake for both groups. Typical high-volume water drinkers experienced a "decrease in contentedness, calmness, positive emotions, and vigor/activity" when asked to drink less water than usual after three days. Typical low-volume water drinkers experienced the opposite when asked to drink more water than usual during those three days, experiencing a "decrease in fatigue/inertia, confusion/bewilderment, and thirst and a trend to lower sleepiness."

The group that drank a smaller amount of water during the three-day trial period complained of headaches, thirst, sleepiness, and difficulties in concentration. So whether you're being encouraged to drink more water from a fitness influencer or not, take this as a sign to fill up your water bottle ASAP.

How much water should you drink for a positive mood?

If you look at the study, the group that experienced an improvement in their mood drank 2.5 liters of water a day, which is around 10.5 cups of water. The group that didn't feel as good and experienced a decrease in their mood only drank 1 liter of water during the day, which is only 4 cups of water during the day.

It's also important to note that every single body is different and the amount of water your body needs will be different compared to others. An easy way to determine how much water you should drink in a day is through a simple calculation. Simply divide your body weight in half and drink that number in ounces. So if you're 160 pounds, you should be drinking 80 ounces of water a day—which equates to 10 cups. Here's more to know on how much water you should be drinking every day.

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Kiersten Hickman
Kiersten Hickman is a senior editor at Eat This, Not That!, with a main focus on food coverage, nutrition, and recipe development. Read more
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