Welcome to Bad Science on the Internet! In this series, we highlight some of the crazy, funny,  and downright dangerous stuff people post online – then we give you the facts.  

The Bad Science: Ozone Therapy

What do they claim?  Suggested uses include treatment for all types of infectious diseases, arthritis, Alzheimer’s, cancer, and numerous other conditions

Are they trying to sell you something?  Yup, you need a special machine to generate the ozone and the “treatments” will cost $100-$150 per session.  Multiple sessions are generally recommended.

Is any of this true?   Surprisingly, ozone therapy has been studied in some medical settings.

There is no doubt that ozone has anti-microbial properties, and that it can be used to sterilize instruments or rooms at sufficiently high concentrations.  While not approved in the US, it has been used in elsewhere in the world to treat localized infections when dissolved in a liquid and applied to the wound.  Several groups are also studying the effects of localized ozone delivery to reduce herniated disc swelling or to active the body’s anti-oxidant defenses when given along with investigational new drugs.

However, none of these uses have been proven in large clinical trials, and the US FDA has not approved ozone therapy for the treatment of any of these conditions.  In fact, the FDA takes a very negative view of ozone therapy, saying: “Ozone is a toxic gas with no known useful medical application in specific, adjunctive, or preventive therapy.”  I know there are folks out there who don’t trust the government or the FDA, but it is the FDA’s job to independently verify the safety and efficacy of new therapies.  Ask yourself this – if ozone therapy really worked, wouldn’t someone try to get it FDA-approved in order to sell it and make a boat-load of money?  Yes, they would, and it turns out they have tried – there have been several ozone therapy clinical trials in the US.  None have been able to demonstrate that this therapy is safe and efficacious to the FDA’s standards.  Read the the FDA’s full position on the safety of ozone here.

Is any of this dangerous?  Oh yes, I’m afraid so.  You have probably heard of the ozone layer, which protects us from solar radiation, but down here on the earth’s surface, ozone is not very good for your lungs.  It can cause chest pain, coughing, airway irritation/inflammation, and can worsen bronchitis, emphysema, and asthma.  Remember the Beijing summer Olympics?   Many athletes were worried about the air pollution, and ozone is was one of the major concerns.  The EPA standard for acceptable levels of ozone in the air we breathe is 0.075 parts per million (ppm).  That is very low – much, much less then would be used in ozone therapy.

Ozone causes lung and tissue damage the same way it kills bacteria – it acts as an oxidant.  Oxidants produce harmful reactive oxygen species which can damage cells, and too many reactive oxygen species overwhelms and kills cells.  You have probably heard of anti-oxidants, and we know these are good for you.  The reason you need anti-oxidants in your diet is to fight the oxidants.  So, perhaps purposely exposing yourself to a oxidant is not the best idea?  (It’s not.) There is a clear consensus that ozone is a broad-spectrum cytotoxic agent – toxic to all cells (yours as well as bacteria) and the reason it’s not used as an anti-microbial therapy in the medical setting is that we generally prefer anti-microbial agents that are more toxic to bacterial/fungus etc than they are to our own cells.

I focused on the danger to the lung, because this is how people are generally exposed to ozone (a gas). The only way you would reasonably be exposed to large doses of ozone in other ways is ozone therapy, which sometimes involves vaginal, rectal, intramuscular, subcutaneous, and even intravenous (!) administration. Ozone is cytotoxic by any route, though this may manifest  differently, since different organs and tissues will be damaged. Please don’t let anyone convince you it is a good idea to inhale or inject ozone into your body. With high enough doses, this can be fatal.

What’s the bottom line?  Ozone therapy is not approved for use to treat any condition. There is simply no proof of efficacy or safety.  Ozone is also a cytotoxic oxidant that you generally want to avoid.  It is very harmful to the lung, and is a regulated and monitored environmental pollutant.  If your doctor recommends ozone therapy, it might be time to find a new doctor.

Some references:

https://www.epa.gov/ozone-pollution/ozone-basics#effects

https://fas.org/sgp/crs/misc/R41062.pdf