Most of us are aware of the dehydration that happens in the hot days of a year and in the occasion of certain illnesses, such as diarrhoea and fever. Although those are great causes of dehydration, we are not aware of less dramatic causes of it.
During our daily lives we often neglect the adequate intake of water, especially during the busy work days, work out sessions and sauna evenings. At offices we might drink plenty of coffee and tea, which act as mild diuretics and therefore do not add to the daily liquid intake. Instead, drinking coffee and tea might even have a negative effect on the hydration levels as we are supposed to drink a matching amount of water with it, which doesn't always happen
Keeping in check with the proper hydration increases your mood and general wellbeing, and since we often spend the majority of our waking hours at work, it would make sense to invest in making it as pleasant and efficient as possible, not mentioning the time you spend after work which also suffers from the symptoms of the less than optimal mood.
Moreover, especially in Finland where many of us love taking saunas it is very likely that we don't hydrate adequately. Many even drink alcoholic beverages during a sauna session and might even eat salty foods, such as sausages, with it. In the occasion of the sauna being over 80 degrees celsius and the bathing sessions are longer, the need for rehydration gets critical. Some people love to take a sauna after a work-out which makes it really easy to dehydrate yourself which contributes to a non-optimal state of being afterwards.
Summarizing, remember to keep yourself hydrated - even in the winter time!