Do you sometimes feel more irritable, anxious, or tired than usual, for no apparent reason? Perhaps the cause isn’t as deep or complex as you imagine. Perhaps you don’t have to delve into your subconscious for some latent conflict or hidden trauma. The problem could be brain hydration, and the solution could be as simple as paying more attention to how much water you’re drinking, because your mental health depends on it too. And that’s not an exaggeration.
In a world where we constantly talk about taking care of our mental health, we continue to overlook such an essential factor as water. It’s not only vital for your body, it’s also crucial for our minds. But since almost no one reminds us of this, we tend to overlook its influence. Spoiler alert: your brain won’t be very happy.
The body asks for water, the mind too
Before you head out to find the next guided meditation to reconnect with your inner self, ask yourself: Have I drunk enough water today? Because your brain, like any other organ, needs to be hydrated to function properly. And if it isn’t, the consequences will soon become apparent.
The problem is that we often misinterpret these signals.
We think we’re “stressed” because of a demanding job, because we have a thousand tasks pending, or because we’ve had an argument with someone. And yes, that may be true. But if we’re not well hydrated on top of that, everything is amplified. A small problem feels like a tragedy. A neutral comment feels like an attack. A simple task seems like a mountain. Sound familiar?
A study conducted at the University of Valladolid found a correlation between mild dehydration and anxiety. In fact, more than 90% of participants did not drink enough water to replace what they lost throughout the day. Of these, approximately 97% had trait anxiety levels above 85%.
Interestingly, the researchers noted that “participants reported feeling calmer and more alert immediately after drinking water.” Their results, in line with other research, suggest that hydration can affect neuronal function and our mood.
In fact, another study conducted at the University of Isfahan found that not drinking enough water (less than two glasses a day) is linked to a higher risk of developing depression and anxiety. Furthermore, French researchers also confirmed that hydration directly influences our level of satisfaction, calmness, and emotional state.
The mental health consequences of not drinking enough water
The brain is largely composed of water (75%, to be exact). Therefore, it needs it to perform many of its basic functions, from regulating body temperature to maintaining concentration, transmitting nerve impulses, and regulating emotions.
When you’re not well hydrated, your cortisol (the stress hormone) levels increase. This not only creates a state of hyperarousal, but also discomfort and nervousness. Furthermore, it has been observed that the plasma availability of some hormones, such as norepinephrine, which plays an important role in depression, varies.
In fact, a 1% drop in hydration is enough to cause cognitive functions such as attention, short-term memory, and thinking to deteriorate by approximately 5%.
The catch? The sensation of thirst doesn’t appear until we’re 1–2% dehydrated. But by that point, dehydration has already begun to take its toll on our mind and mood. Therefore, it’s best to drink even if you’re not particularly thirsty, to ensure you maintain an adequate level of hydration. Your brain will thank you for it.
One last reminder
Sometimes we look for complex solutions to simple problems. If you’re feeling down, anxious, irritable, or have brain fog that prevents you from thinking clearly, check the basics first. Eat well, get enough sleep, and… drink water. Because your emotional well-being doesn’t depend solely on your thoughts. It could also be in your water bottle.
Seems too simple? Maybe. But if you don’t tend to drink much, you might not need a therapist but something much simpler: a glass of water—or several.
References:
Castro-Alija, M. J. et. Al. (2023) Association between Anxiety Status and Hydration Status in Spanish University Students. Nutrients; 16(1): 118.
Zhang, N. et. Al. (2019) Effects of Dehydration and Rehydration on Cognitive Performance and Mood among Male College Students in Cangzhou, China: A Self-Controlled Trial. Int J Environ Res Public Health; 16(11): 1891.
Haghighatdoost, F. et. Al. (2018) Drinking plain water is associated with decreased risk of depression and anxiety in adults: Results from a large cross-sectional study. World J Psychiatry; 8(3): 88-96.
Pross, N. et. Al. (2014) Effects of changes in water intake on mood of high and low drinkers. PLoS One; 9(4): e94754.
