What is alkaline water? — Explainer video

Transcript

What is alkaline water? The pH value, simply explained.

Alkaline water has a pH above 7. At 7 a solution is neutral; below that, it is acidic. Lemon juice sits at around pH 2, soapy water around 9.

On its way, water dissolves substances from air and rock. Carbon dioxide forms carbonic acid and lowers the pH. Hydrogen carbonate from the rock raises it and buffers it: the value stays stable, even when a little acid is added.

Naturally alkaline water forms slowly in the rock. Buffered by minerals, it holds its pH. Water ionisers split tap water by electrolysis: the alkaline part can reach pH 9 or more, but it is weakly buffered and falls again once the water absorbs carbon dioxide from the air.

Does alkaline water de-acidify the body? No. The body keeps the pH of the blood between 7.35 and 7.45 on its own. Buffers in the blood, the lungs and the kidneys take care of this, regardless of what a person drinks.

In the stomach, every glass of water first meets gastric acid at a pH of roughly 1.5 to 2. A genuine shift in the acid-base balance belongs in the hands of a doctor. Anyone with a kidney or metabolic condition is best advised to talk to a doctor about their drinking and eating habits.

Why do people drink alkaline water anyway? Water rich in hydrogen carbonate tastes mild and soft. Water from limestone-rich rock brings calcium and magnesium, which the body needs every day.

The water of Piz Sardona seeps into the ground at more than 2,000 metres above sea level and travels through the rock for around twelve years. Along the way, it takes on its natural pH of 8.0, together with 540 milligrams of minerals per litre.

More on this in the Piz Sardona Academy.