Did you know that the adult human body is actually 60 percent water? Or that blood is 90% water? Well one thing is for sure, everyone knows it is important to stay hydrated. What many of us don’t realise is just how the positives of drinking water goes beyond simply the physical health benefits. Hydration has an impact on the brain and research has shown that even mild dehydration can have a negative impact on energy levels and moods. Here is how.
Studies have found that our brains are strongly influenced by our hydration status. Even mild dehydration, such as the loss of 1–3% of body weight, can impair many aspects of brain function. In a study in young women, researchers found that fluid loss of 1.4% after exercise impaired both mood and concentration. The same research team conducted a similar study in young men. They found that fluid loss of 1.6% was detrimental to working memory and increased feelings of anxiety and fatigue. While that may seem like a strange way of talking about dehydration, it equates to about 2 litres of water, and could easily take place through normal, daily activities. It doesn’t take much to feel the negative impacts.
When it comes to the negative impacts of dehydration, there are some significant links to depression; in fact, one resulting symptom of chronic dehydration actually turns out to be depression. Not drinking enough water impedes energy production in our brain, which in turn effects the brain’s functions. The resulting mood disorders that result from this type of dysfunction can be categorised with depression. Further to this, dehydration impedes your brain’s serotonin production. Depression is frequently related to subpar levels of serotonin, which is a critical neurotransmitter that heavily affects your mood. Serotonin is created from the amino acid tryptophan, but sufficient water is needed for this process.
If reducing levels of stress is important, regularly staying hydrated is going to help achieve that. Researchers have found a link between production of cortisol (the stress inducing hormone) and low levels of hydration. In fact, it’s a self-perpetuating cycle: when we are stressed, our adrenal glands produce extra cortisol, the stress hormone, and under chronic stress, our adrenal glands can become exhausted, and result in lower electrolyte levels. Therefore, drinking sufficient water can help reduce the negative psychological and physiological impacts of stress.
As with depression, dehydration rarely causes anxiety as a cause by itself, but not drinking adequate water puts us at risk for increased anxiety symptoms now, and possibly the development of higher anxiety levels in the future. In short, dehydration causes stress, and when our body is stressed, we experience depression and anxiety as a result. Therefore, we want to ensure we are properly hydrated daily, especially if we are naturally anxiety-prone.
If drinking lots each day is going to benefit us this much, what about all those cups of coffee and tea? Can they count towards daily water intake to feel the benefits? Well, it turns out that they are contributing in a positive way. Whilst it is widely discussed that increased levels of caffeine in the bloodstream can lead to heightened anxiety, the water within each drink we consume, adds a net positive to our level of hydration and thus can be considered to contribute in a good way. Does that mean you should only be drinking these in a day? No, sadly not.
When it comes to exercise, and the summer months, it becomes even more important to consume greater levels of water in a day. The fundamental reason for this: sweat. With increased perspiration, we lose more fluids from our body to regulate our temperature and therefore need to take more water on.
So, while there is no universally agreed quantity of water that should be consumed daily (although two litres is most often the guide), the commitment to drinking enough each day will positively affect your mental wellbeing. The potential to avoid unnecessary stress, the reduction in anxiety triggering hormones and alleviating the affects of depression are justification enough to grab a glass and fill it up. Even if it does mean a few more visits to the toilet a day…
Want to know more about ways in which you can improve your overall wellbeing? Have a read of Kate's article which discusses the importance of sleep, and ways to maximise the benefits.