"The Water we get from food rarely exceeds 20% of our total water intake. Even if your diet is extremely high in fruits and vegetables and soups you will rarely exceed probably 30 to 40% of your total water intake. So the answer is no, it is practically impossible to stay hydrated if you just wait to get your water from solid foods. So this is definitely a big myth."

"Drinking water in the morning is a very good idea since for, I would say at least 6-8 hours per day, during our sleep, we do not drink anything. So when we wake up in the morning our body has very low levels of water and it's a very good idea to start your day by drinking some water. So I would say drinking water in the morning can probably by the first step to start your day, energize your day, and help you stay hydrated throughout the day. So I would say this is a fact, and drink water in the morning. "

"The short answer is no, because the swimmer is less at risk than other athletes. The reason for this is that it's much easier to lose the heat produced during exercise to the surrounding water for the swimmer, than to the surrounding air for the runner or the cyclist.

Because of that, actaully the swimmer is much more at risk of becoling hypothermic than hyperthermic during exercise.

So he needs to drink less than, for example, runners or other athletes. So it is a myth to believe that the swimmer needs to drink as much as other athletes."

"Well...stress is generally related to negative feelings, but from a psychological point of view we know that there is good stress, or well-being, and bad stress. And we recently demonstrated in our studies that good hydration has a positive influence on stress. Well hydrated people generally report to be more happy, less focussed and more alert.  On the other hand, dehydrated people generally report to be less content, less calm, more confused and less happy. 

Consequently, we can say that good hydration has a positive influence on stress, and wellbeing. On the other side, dehydration has a negative influence on stress and induces bad stress. So, good hydration has an influence on stress. This is a fact."

"The short answer is yes, because their main ingredient is water, and to be hydrated you need water. But the long answer is that these drinks not only contain water, but also minerals and sugar, and this is not always appropriate to remain hydrated.

These drinks contain minerals and sugar because during prolonged exercise this can be beneficial because the loss of minerals is important and sugar can improve endurance performance. But for a regular fitness exercise session, mineral loss is small, and adding sugar may add unwarranted calories and it’s probably not optimal. For this reason the idea that sports drinks are efficient to stay hydrated in all circumstances is probably a myth."

"Does being hydrated help burn calories?  Well it is a fact that if you hydrate you will be able to burn more fat, and in some studies we see that it can help people burn more calories but it's only under certain situations where we see that. 

And when you drink water instead of something else you’re burning, basically,  the calories that you have on board and that helps with weight management. When you are drinking other beverages, the calories that come in the beverages are burned before the calories that you already have on board. So, in terms of what beverage to pick for hydration, definitely water it's a fact, drinking water will help burn fat and calories."

"It’s interesting that in the 1930’s there was a small study done on medical students that showed that when they consumed caffeinated drinks, their output of urine for a few hours increased. However, the researchers in that study did not investigate total body water and did not look at markers of hydration status. So, to counter that study, about eight years ago university students were studied in our laboratory in the United States. We looked at the question of what would happen if 500 mg of caffeine were consumed each day, or about half of that amount, roughly 250 mg. Or if 0 mg of caffeine were consumed each day. And indeed we found by looking at over 20 biomarkers of hydration state, that they were not dehydrated. This explains why we don’t see millions of people in emergency rooms of hospitals who are dehydrated because they consumed caffeinated beverages. So in my opinion, it is a myth that caffeinated drinks cause dehydration."