Alkaline water - water that has been treated to have a higher pH level than the 6.5-7.5 pH range - is experiencing a surge in popularity.

There are a variety of alkaline water brands on the market. One brand achieved a pH of 9.5 after putting regular water through an ionizing process that removes acidic components.

Marketing claims behind alkaline water are based on the acid-ash hypothesis. The idea is that eating certain foods, like meat, dairy, and eggs, results in acid ash in your body, which increases your acid levels and causes health problems.

While there are some poorly designed studies that suggest alkaline water confers health benefits, there is no rigorous scientific evidence to support this belief.

You can't change the pH of your body by drinking alkaline water. Your body regulates its blood pH in a very narrow margin. If your pH varied too much, you wouldn't survive. 

However, your diet does affect the pH of your urine. Most people's urine is about 6, which is acidic and not a problem. Alkaline may make your urine less acidic, but it doesn't make a difference to your health.

Alkaline water is so popular because it is a sciency-y idea that sounds plausible. There is a thirst for unique strategies for maximizing health and avoiding disease.

Alkaline water is also part of a rising connoisseurship around water. Bottled water became the number one drink in the US for the first time in history. Those who feel healthier are probably drinking more water than they were before, which is a good thing.