A: In short, for most people, plain water is better. But first, it’s important to understand the definition of alkaline water. Scientists use pH to describe how acidic or basic a substance is, with a range from 0 to 14. Pure water has a pH of 7, meaning it’s neutral. Fluids with a pH under 7, such as coffee and soda, are acidic. Substances with a pH over 7, such as baking soda, are basic, or alkaline.
Alkaline waters have a pH around 8 or 9. Some vendors use water that has a naturally higher pH, while others say that they create alkaline water through an ionization process.
Alkaline water companies make a host of claims, saying it’s better at rehydrating the body, and that it will detoxify and “balance” your body, help you lose weight, and prevent or even treat cancer. However, there’s little credible research showing that alkaline water benefits your health in any important way. In general, be wary of promoted research on alkaline water, as some of these studies are small or funded by alkaline water companies.