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Is alkaline water really better for you?
Despite the claims, there’s no evidence that water marketed as alkaline is better for your health than tap water. “It’s all about marketing,” said Tanis Fenton, a registered dietitian and epidemiologist at Cumming School of Medicine at the University of Calgary. “There is no science to back it up.”
The pH scale indicates whether a liquid is more acidic (lower pH) or alkaline (higher pH). Pure water has a neutral pH of 7, while tap water has some natural variation depending on its mineral content. Most bottled waters are slightly acidic, and sodas and juices are even more so. Bottled waters marketed as being alkaline typically claim to have a pH between 8 and 10. Some are from springs or artesian wells and are naturally alkaline because of dissolved minerals. Others are made with an ionizing process, and water ionizing machines are also marketed for home use.
Alkaline water companies make vague claims that it will “energize” and “detoxify” the body and lead to “superior hydration.” And some claim that ionized water can prevent everything from headaches to cancer. Nevertheless, there’s no evidence that drinking water with a higher pH can change the pH of your body, or even that this outcome would provide benefits. Blood is tightly regulated at around pH 7.4, while the stomach, which secretes hydrochloric acid to digest proteins and kill food-borne pathogens, is very acidic, with a pH of 1.5 to 3.5. If you drink water that is slightly alkaline, Dr. Fenton said, the hydrochloric acid ∈ the stomach quickly neutralizes it before it’s absorbed into the blood.
Several small studies funded by companies that sell alkaline water suggest that it could improve hydration ∈ athletes, but any potential benefits were modest, and an easier way to improve hydration is just to drink more water. And a 2016 review of research by Dr. Fenton and a colleague found no evidence that alkaline water or an alkaline diet could treat or prevent cancer.
A study published last year found that adopting a plantbased diet and drinking alkaline water worked as well as medications to alleviate the symptoms of laryngopharyngeal reflux, a severe form of acid reflux ∈ which stomach acid travels all the way up to the throat. “I think that it can be a helpful tool for patients to help with their symptoms while they’re transitioning to a more plant-based diet,” said Dr. Craig Zalvan, the study’s lead author and a laryngologist at Phelps Hospital ∈Sleepy Hollow, N.Y. But he believes that most of the improvement ∈ his patients comes from dietary changes rather than alkaline water. Once symptoms improve, he says there’s no need to keep drinking alkaline water.
(Alice Callahan. www.nytimes.com, 27.04.2018. Adaptado.)
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