Myth: You have to drink eight cups of water per day

You hear it so often that eight cups of water a day is necessary for everything from weight control to cleansing the body that it seems it must be truth, but the reality is there is no good evidence to support this claim. In fact, this age-old myth is believed to have originally stemmed from a 1970s textbook that made the statement that the human body needs a bit more than two litres (8 cups) of fluid per day from all sources, including coffee, tea, milk, juice, pop and, yes, even alcohol. While we have sadly learned since then that alcohol is not good for hydration, we do know that virtually all fluids do hydrate us, including caffeinated drinks such as tea and coffee, so long as you are habituated to them. When it comes to weight, remember some drinks, such as pop and juice, contain quite a few calories, so sticking to water is usually best. Some individuals, including athletes, those at risk for kidney stones, and pregnant and breastfeeding women, might require extra fluids, but for everyone else, it's all about finding the right amount of fluids for you.

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Gallery: Addressing four common nutrition myths