No, the alkaline diet doesn’t cure cancer

Anyone confronting a cancer diagnosis is eager to find information that might help their prognosis. But the internet can be a tricky resource, with some less-than-accurate advice for people desperate for ways to stay healthy.

A recent Facebook post falls into that misleading category, claiming that "alkaline foods" can heal a number of ailments, as vague as pain as serious as cancer.

The post was flagged as part of Facebook’s efforts to combat false news and misinformation on its News Feed. (Read more about our partnership with Facebook.) 

The so-called alkaline diet sometimes comes up in connection with cancer treatment and prevention strategies. It’s based on the theory that some foods cause your body to produce more acid, which is harmful. 

Because some studies have shown that cancer cells thrive in highly acidic environments, the idea behind this diet is that consuming certain foods and drinks can change your body’s acid level, making it inhospitable for cancer. 

But there are a couple big catches. 

Featured Fact-check

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stated on March 18, 2024 in a Facebook post

Image shows a Princess Kate “stunt double.”

First, according to the MD Anderson Cancer Center, the studies that suggest acidic environments help cancer cells grow relied on cells in a dish — "they do not represent the complex nature of how tumors behave in the human body." 

Second, "there’s no way the foods you eat can alter the pH level of your blood," senior clinical dietitian Maria Petzel says on the center’s website. 

UC San Diego Health nutrition expert Traci Roberts said on the university’s website that the lungs and kidneys are largely responsible for controlling the pH levels of our blood.

What that all means is that while the diet can improve your overall health, and even help lower your cancer risk — it encourages healthy eating like consuming more vegetables and fruits, drinking lots of water and cutting back sugar, alcohol, meat and processed foods — it won’t heal your body of cancer, as the post claims.   

There’s no one diet or food that can cure cancer, according to MD Anderson. But what you eat can affect how you feel with or without a cancer diagnosis. 

We rate the claim that an alkaline diet can cure cancer False.