Water is by far the best liquid that we can give to our bodies, as it is free of additives and calories. Even natural fruit juice can be bad for you if you drink too much of it, because of the high sugar content. Sports drinks and soda have lots of added sugars/syrup too so water is the best way to keep your body hydrated.
I religiously drink a big glass of warm water first thing in the morning, as that improves blood circulation (drinking hot water helps your arteries expand and carry blood more effectively), soothes the digestive tract and activates metabolism. I sometimes add a squeezed lemon to it for vitamin C and to give it some flavour.
Throughout the day, I try to drink at least 1l of water in addition to other fluids I might intake. I would practically have to live in the toilet if I drank more than 1.5l. Unfortunately, I think drinking water is an active choice - since it has no flavour it's not something most people would crave. A water bottle really helps I feel. I like this one that has markings - this is how much you should have by 11am, this is how much you should have by 5pm etc. Makes it feel like a competition and you really want to get there
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