What was claimed
Cancer is caused by cells being 'bathed in acid' and eating alkaline foods ensures cancer cannot thrive.
Our verdict
False. You cannot change the body’s pH by eating alkaline foods and the acidic environment surrounding cancer cells is a byproduct of cancer, not the cause.
AAP FACTCHECK - Cancer is caused by cells being “bathed in acid” and eating alkaline foods can change the body’s pH, ensuring cancer and disease cannot thrive, according to social media posts.
This is false. Eating alkaline food does not change the body’s pH, and while cancer cells are found in acidic environments, this is a byproduct of cancer’s growth, not the cause.
The claim appeared in an Instagram post that states “Cancer and disease cannot thrive in an alkaline environment”.
“How do we do that ? By eliminating the things that cause an imbalance in our PH levels like excessive processed sugars, excess grains, excess alcohol, processed meats, stress and excess caffeine.”
It goes on to suggest that consuming more alkaline foods “like lime, cucumber, chickpeas” can act as cancer remedies.
The post includes a video clip of a man who says “every cause of cancer, the root cause, is the cell being bathed in acid”.
This video is taken from an almost hour-long presentation on YouTube, which promotes a machine that supposedly makes water more alkaline. The presenter claims drinking alkaline water has a range of health benefits.
Experts told AAP FactCheck that it’s not possible to change the body's pH level by consuming certain food and drink, and that an acidic environment isn’t the root cause of cancer.
University of Otago cancer researcher Professor Margreet Vissers called the Instagram post “the worst kind of misinformation, where a grain of truth is bent, misinterpreted and exaggerated until it becomes a nonsense”.
She said that cancer cells expel lactic acid as they grow, which can make the surrounding environment acidic.
“However, this (mildly) acidic environment is NOT the cause of the cancer, it is the result of the cancer,” Prof Vissers said.
“The acid does not feed the tumour, and removing the acid will not shrink the tumour."
Consuming alkaline foods or drinks has no impact on tumour growth, she said.
“Hence there is no evidence whatsoever to suggest that there is any basis for supporting the claim that drinking alkaline water will help cancer patients at all,” Prof Vissers added.
University of Auckland cancer researcher Petr Tomek agreed that acidic environments don’t cause cancer, but are a byproduct of the rapid growth of cancer cells.
Dr Tomek also said it’s not possible to change the body’s pH by having an acidic or alkaline diet.
“The body has very robust systems for regulating pH that cannot be easily overridden” Dr Tomek told AAP FactCheck.
The Australian Cancer Council stated online that while it’s possible to change the pH of urine by eating foods that are acidic or alkaline, the pH of the body is tightly regulated and unaffected by diet alone.
It said there’s “no good evidence” that eating alkaline food can prevent or treat cancer.
Cancer Research UK added that eating an alkaline-rich diet may lead to malnourishment, as this diet may lack iron, calcium, zinc, vitamin B12 and vitamin D.
A 2016 systematic review, published in the medical journal BMJ, found there was a lack of evidence that the pH level of food or water could cause or prevent cancer.
The authors concluded that “promotion of alkaline diet and alkaline water to the public for cancer prevention or treatment is not justified”.
The Verdict
False – The claim is inaccurate.
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