What Happens to Hydrogen Peroxide in the Digestive System?

I don’t know, but I have a lot of questions!

I’ve just recently encountered the idea that hydrogen peroxide might help cure many ailments, including COPD. Now, there is absolutely no evidence supporting the idea that ingesting (diluted) hydrogen peroxide will do anything but irritate your stomach. And anyone claiming to have any cure-all is blowing smoke up your a…er…anatomy. The websites claiming to tell you how to use hydrogen peroxide as a cure are: badly formatted, copy-and-pasted from each other, misusing scientific vocabulary, and asking for money.

Because this ‘hydrogen peroxide cure’ claim is so outrageous, no-one has attempted to see what drinking diluted hydrogen peroxide might do to a person. And I think that’s fine. Except that people ARE following this internet advice and drinking hydrogen peroxide. What might it be doing to these people?

At first glance, I thought that the answer might be simple. But I’ve spent way too much time on this question, and there is no obvious answer.

At first, I thought that it was possible that hydrogen peroxide could make it down into the gut, and get absorbed into the bloodstream from the gut. Once in the bloodstream, perhaps hydrogen peroxide decomposes into water and oxygen. I’ve read just this argument from those pushing hydrogen peroxide as a cure. Mostly they say that hydrogen peroxide breaks down into oxygen, and oxygen is especially toxic to cancer cells, so hydrogen peroxide will help kill cancer cells. Well. There are so many uncertainties around this argument that I’m having a hard time knowing where to start. But start I will. Here I go…

Is hydrogen peroxide absorbed by the digestive system? The digestive system is one continuous tube through the body, and the only way molecules are absorbed into the body is if they pass through the cells lining the intestines. Cool, you say. Hydrogen peroxide is a tiny molecule (only four atoms big) it can diffuse through the intestine lining. Smart answer, I say. I’d thought of it too (aren’t we all so clever here). Turns out movement of hydrogen peroxide through cells is highly regulated (it’s a toxic byproduct of metabolism, and is also used in cell-signalling and to breakdown pathogens). Cell membranes probably do not allow the passage of hydrogen peroxide, at least not through simple diffusion, or in significant quantities.

Does hydrogen peroxide breakdown into water and oxygen in the bloodstream? There are small amounts of catalase (the enzyme that facilitates the decomposition of hydrogen peroxide) in the bloodstream, but hydrogen peroxide will also react with other components of the blood. If hydrogen peroxide did get into the bloodstream, some (if not most) of the compound might undergo reactions that don’t create oxygen. Now, some people inject themselves with hydrogen peroxide, and it’s just as well that it doesn’t immediately, or entirely, decompose into oxygen and water, as the oxygen would form bubbles and greatly increase the risk of these injectors dying of or being crippled by embolisms.

Does hydrogen peroxide exist long enough in the digestive tract to be absorbed into the bloodstream? Maybe not. I suspect that the food present in the digestive tract would react with the peroxide long before it got absorbed. And if hydrogen peroxide was to be consumed with an empty stomach, it might just react with the outer layer of cells of the mouth, throat and stomach. We know that hydrogen peroxide does react with our cells, because high concentrations of hydrogen peroxide (35+ percent) burn the skin. Skin is mostly epithelial tissue, the same tissue your digestive tract is lined with.

What causes hydrogen peroxide to burn skin? I found an answer on Quora suggesting that peroxide burns are little oxygen bubbles in the capillaries of the skin. I doubt this mechanism causes the burns, as hydrogen peroxide would have to be absorbed into the bloodstream and decomposed into oxygen, and we’ve covered why these occurrences are unlikely. I suspect that, as a strong oxidiser, hydrogen peroxide reacts with the compounds in the outer layers of the skin.

Could hydrogen peroxide possibly cure ailments? Our bodies produce and breakdown hydrogen peroxide constantly. It’s very hard to see how exposing ourselves to more would do anything for us at all. One, very far out possibility, is that the body has receptors that detect the products of compounds oxidized by hydrogen peroxide, and that some of these receptors might send signals to the immune system. Perhaps the triggered immune system would then be more likely to detect and destroy disease-causing cells. The possibility is so far out there, and such an uneducated guess, I hesitate to even mention it. If you take this conjecture and do anything with it other than scientific research, don’t. I will find you.

If you are a biochemical student or medical student looking for a thesis topic, you are welcome. Anyone else… why are you still reading this? Thanks, I guess!