If something online promises to cure everything, it's probably too good to be true.
One of the most dangerous examples? Chlorine dioxide is often marketed under names like "Miracle Mineral Solution (MMS)" or "aerobic oxygen", buzzwords that hint at health and vitality.
But in reality, these products can make you violently ill within hours – and in some cases, they can be fatal.
Despite what the name suggests, MMS is not just bleach. Bleach contains sodium hypochlorite, whereas MMS contains sodium chlorite – a different but equally toxic chemical.
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When ingested, sodium chlorite can cause methemoglobinemia, a condition where red blood cells lose their ability to carry oxygen. It can also trigger haemolysis (the rupture of red blood cells), followed by kidney failure and death.
When sodium chlorite mixes with acid (such as stomach acid), it converts into chlorine dioxide, a bleaching agent. This compound has strong antimicrobial properties: it can kill bacteria, fungi and even viruses like SARS-CoV-2.
For that reason, it's commonly used in sanitising dental equipment and hospital tools like endoscopes. Its effectiveness at killing over 400 bacterial species makes it useful in cleaning – but not in humans.
While the mouth and oesophagus are lined with multiple cell layers, offering some protection, the stomach and intestines are far more vulnerable. These organs have a single-cell lining to absorb nutrients efficiently – but this also means they're highly sensitive to damage.
That's why ingesting chlorine dioxide often leads to nausea, vomiting, abdominal pain, and diarrhoea. In extreme cases, the chemical can burn through the gut lining, leading to bowel perforation – a medical emergency with a high risk of death.
Using MMS as an enema is equally dangerous. Chlorine dioxide can trigger an overproduction of reactive oxygen species – unstable molecules that damage cells and contribute to chronic gut conditions. This cellular stress may explain both the immediate symptoms and the long-term injuries seen in reported cases.
It doesn't make a good mouthwash, either
Some sellers claim MMS can be used safely in the mouth because it's found in dental cleaners. But clinical trials show it's no more effective than other mouthwashes, and its oxidising power doesn't distinguish between harmful microbes and healthy cells.
Yes, it may temporarily reduce bad breath, but it also disrupts protein synthesis, damages cell membranes, and harms the gut microbiome – the collection of helpful bacteria we rely on for digestion and immune health.
Chlorine dioxide doesn't just attack the gut. It also affects the cardiovascular system. Documented risks include low blood pressure, fainting, and cardiac damage – including stroke and shock.
In some cases, it causes a dangerous blood disorder called disseminated intravascular coagulation (DIC). This condition causes abnormal clotting, followed by severe bleeding and potential organ failure, stroke and death.
Chlorine dioxide is also a respiratory irritant. Inhalation can inflame the nose, throat and lungs, and in severe cases, cause respiratory distress – particularly with repeated exposure in workplaces.
Studies of factory workers show that even low doses can lead to nasal inflammation, coughing and breathing difficulties. And some patients who drank chlorine dioxide to "treat" COVID-19 ended up with severe chemical lung injuries.
Risks to the brain, hormones and skin
Animal studies suggest chlorine dioxide can harm the nervous system, causing developmental delays, reduced movement, and slower brain growth. It also appears to affect the thyroid, potentially causing hormonal disruptions and delayed puberty.
It doesn't stop there. Some people who consume chlorine dioxide also develop cerebral salt wasting syndrome, a condition where the kidneys lose too much sodium, leading to excessive urination, dehydration and dangerously low blood volume.
Skin contact isn't safe either. Chlorine dioxide can irritate the skin, and lab studies show it can kill skin cells at high concentrations. People who've used it to treat fungal infections have ended up with chemical dermatitis instead.
Chlorine dioxide can be useful for disinfecting hospital tools, dental equipment and water supplies. But that doesn't mean it belongs in your body. Many of its supposed "benefits" come from lab studies or animal research – not from safe, approved human trials.
There's no evidence that drinking it cures any disease. There's overwhelming evidence that it can harm or kill you.
So, if you're tempted by a product that promises miracles with science-y language and zero regulation, take a step back. The risks are very real – and very dangerous.
Adam Taylor, Professor of Anatomy, Lancaster University
This article is republished from The Conversation under a Creative Commons license. Read the original article.