evidence: You can buy water with electrolytes, minerals or completely "purified." You can buy it with the pH changed to make it alkaline. You can purify your own tap water or even add nutrients back into it. But after seeing a video of a pricey, high-tech filter (about $400 U.S. on sale) that you can monitor with your phone, we wondered, how much of our water filtration fixation is healthy, and how much of it is hype? [...] Another confusing water option lining the shelves of grocery stores is alkaline water. Alkaline is a fancy way of saying "basic," and this water's pH is a bit higher than standard tap water. Some proponents say this water can neutralize acid in your bloodstream or help prevent cancer and heart disease, but there's not a lot of research to back that up. [...] "Those things are really worrying," Fenton says. "When there's no health benefits, it's really questionable why anyone would want alkaline water."