Your Diet and Cancer: pHacts and pHiction

This is a companion article to the feature Not so Basic After All: The Role of pH in Cancer Therapy.

Based on your reading of the article above, you may be wondering if an acidic diet can cause cancer, or if you can prevent cancer with a basic diet. While the results of the baking soda study might make it seem that way, science points to a more nuanced reality. 

First, although the acidic pH of a tumor helps cancer cells to multiply, it does not create cancer cells out of nowhere.  For this reason, increasing the pH surrounding a tumor can slow the rate at which a tumor grows, but it cannot prevent the tumor from forming in the first place.  Therefore, consuming a basic substance to neutralize the acidic tumor environment around a tumor can be therapeutic, but it doesn’t prevent cancer. 

Many health food stores sell high-pH water, but you’re better off saving money and drinking from the tap!

It’s also important to note that the therapeutic potential of this approach is limited to very specific foods or drinks.  You’ve probably seen high-pH water at health food stores that claims several health benefits, including that it’s effective against cancer.  However, this water behaves differently than baking soda, and is far less effective.  Baking soda is a special base, in that it takes up protons from the acidic environment of a tumor, but not from the rest of the body.  Baking soda remains like a dry sponge as it travels throughout the body, until it reaches the tumor, where it starts to soak up protons.  In contrast, the high-pH water takes up protons from anywhere in the body.  This base is already like a saturated, dripping sponge by the time it gets to the tumor, and cannot soak up any more protons.  Therefore, baking soda and other specifically-designed substances are much better than high-pH water at neutralizing the acidic tumor environment for cancer therapy.  In conclusion, the pH of your diet will not prevent cancer, and only certain basic foods or drinks may help to treat it!

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Sarah Anderson is a PhD candidate in the chemistry department at Northwestern University.


  • Sarah Anderson is a PhD candidate in the chemistry department at Northwestern University and a science communication enthusiast. Check out her Twitter page @seanderson63 to read more of her science writing.