My friend Tim Caulfield, a Canada Research Chair in Health Law and Policy at the University of Alberta, author of “Is Gwyneth Paltrow Wrong About Everything?: How the Famous Sell Us Elixirs of Health, Beauty & Happiness” (Beacon, 2015) and host of “A User’s Guide to Cheating Death” on Netflix (that’s a long bio) writes for NBC News, humans need water but the marketing of water as a detoxifying, energizing, health-enhancing, miracle beverage has become a lucrative business. Over the past few years the booming wellness industry (aka Big Wellness) has coopted this most basic of biological needs to sell products and promises of miraculous improved health. But is there any evidence to support the hydration hype?

Before I dump on the water business, let’s give a nod to the positives. There is growing recognition that sugary beverages are not a good choice, nutrition wise. Evidence suggests that consumption of sugary beverages, especially soft drinks, is associated with a range of health issues, including obesity and heart disease. As a result, there is a broad consensus among nutrition and public health experts about the value of limiting the consumption of these calorie-dense and relatively nutrition-free beverages.

So, in this context, the shift to water is a very good thing. But that doesn’t mean we have to buy what the “premium” water market is selling.

But before we get to the fancy packaging, we need to talk about volume. Do you actually need to drink eight glasses of water a day? In a word: Nope.

This strange and incredibly durable myth seems to have emerged from a misinterpretation of a 1945 US Food and Nutrition Board recommendation. That document suggested a “suitable allowance of water for adults is 2.5 litres daily” (i.e., roughly eight glasses a day). But what is almost always overlooked is that the recommendation — which was not based on a robust body of research — also noted “[m]ost of this quantity is in prepared foods.” In other words, you already get the bulk of your needed water from the food you eat.

In reality, there is no magical amount of water. We do need to stay appropriately hydrated, of course. And as our climate and activities change, so does the amount of water we lose through sweating etc. But our bodies are good at telling us how much and when we should drink. (Thanks, evolution.) And all liquids — coffee, tea, that weird fluid inside hotdogs — count toward your daily consumption of water. My body can’t tell if an H20 molecule came from a fresh-water spring on the side of a remote Himalayan mountain or from a cup of gas station java (which isn’t, despite conventional wisdom to the contrary, dehydrating).

But even if water is found in a lot of foods and beverages, pure bottled water is still better for us, right? Wrong again.

Yes, drinking plain water is almost always a better choice than some other, sugar-infused, beverage. But the water you drink doesn’t need to come out of a plastic, glass, or 24-karat gold (yes, that is a thing) bottle.

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Studies have shown that some people believe bottled water is healthier than tap water. That perception is wrong. In fact, tap water in the U.S. and Canada is almost always the best, cheapest and most environmentally friendly choice. Bottled water can be essential during emergencies that disrupt the supply of clean water. And there have been scary examples of contaminated public water — the Flint, Michigan water crisis being only one recent example.

We also need to be vigilant to ensure our public water supply remains clean. But in most places in the United States and Canada, tap water is tightly regulated and safe. Not only that, but tap water can have less contaminants than bottled water. A study from Canada, for example, found that 70 percent of the tested bottled water brands contained high levels of bacteria and generally had more bacteria than tap water. A 2019 Consumer Report investigation concluded “that in some cases bottled water on store shelves contains more potentially harmful arsenic than tap water.”

But bottled water tastes better, you say! Actually, blind taste tests have consistently found that to be untrue too. To cite just one example, only one-third of the participants in a Boston University study, were able to correctly identify tap water. One third thought it was bottled water and one third couldn’t tell the difference.

But bottled water tastes better, you say! Actually, blind taste tests have consistently found that to be untrue too.

And now we get to what is probably the biggest scam. Wellness wonks have been pushing absurd diets, supplements and potions for decades. Now that same thinking has come to water, with alkaline, hydrogen, gluten and GMO-free water brands hitting the supermarket and health food store shelves near you.

Nope, nope and — sigh — nope.

Alkaline water is part of the larger multimillion-dollar alkaline diet fad embraced by celebrities like New England Patriots quarterback Tom Brady. Proponents claim that humans can become too acidic and, as such, we need to consume foods and beverages that will lower the pH of our bodies. By doing so, we will improve our health and reduce the incidence of disease and cancer, the theory goes.

Problem one: There is little evidence to support the entire premise that adjusting the pH of your food will have an impact on our health. And the studies that have explored the claim have found little benefit to this dietary approach, outside of the diet’s push to eat more fruits and vegetables. (Eating more fruits and vegetables is of course good for you hand can help you stay healthier for longer.)

Problem two: You can’t change the pH of your body through food and beverages. So the entire premise is scientifically absurd. Your body tightly regulated the pH of your blood. It doesn’t need the help of overpriced bottled water.