Earlier this week, former Victoria's Secret Angel and all-round mega babe Miranda Kerr announced her love for alkaline water.
"I follow an alkaline-based diet and drink between two to three litres of alkaline water every day to stay hydrated," she revealed.
Cue, a gazillion flustered fans taking to Google to find out what on earth alkaline water is.
And - shock horror - it might not actually be that great after all.
We can reveal that alkaline water isn't something you find in a volcanic lake or in science class. It's just water that's less acidic than tap water, because it has fewer hydrogen ions.
Alkaline water is rich in calcium, silica, potassium, magnesium, and bicarbonate, says nutritionist John Berardi.
There have been various health claims that the likes of alkaline water could reduce cancer risk, improve gut health, benefit diabetes patients and generally stave off illness. But, Refinery 29 reports this simply isn't the case.
There are also claims that alkaline water can neutralise acid in your bloodstream, which provides a balance to all the crap you consume such as fatty foods and sweets. But, again, there's no evidence.
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According to Charles Mueller, clinical associate professor of nutrition at New York University, eating or drinking anything that's alkaline isn't going to change your blood's acidity, because your body already has specific PH ranges that aid digestion.
"The pH in your stomach is so acidic that it completely obliterates anything that you’ve had to drink or eat," Dr Mueller told Refinery 29.
"When the food moves into your small bowel, bicarbonate obliterates the acidic nature of the contents coming out of your stomach."
In a blog on The Huffington Post, nutritionist John Berardi says that our bodies do "a fantastic job of maintaining blood pH within each respective range".
He adds: "Secondly if your pH is out of balance, it's important to get to the underlying cause. Without knowing the cause, you can't determine whether alkaline water will really help you."
"What's more, focusing on the pH level of our water is sort of besides the point. Because if alkaline water is helpful, that might be due to the minerals it contains rather than its pH level, per se."
Until the health benefits are scientifically backed up, maybe it's best to just save your money and stick to tap water.