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Manuka Honey

Question
I have read a paper explaining that Manuka honey could not work in CF patients because it can not be inhaled and when taken orally, it would not reach the lung. I am not scientist, hence perpaps this is a silly question, but why can manuka honey not reach the lung when taken orally, but oral antibiotics can?
Answer
Dear questioner,
Mankua honey is a natural product, that contains hydrogen peroxide that has antiseptic properties, but is an instable molecule. Furthermore, it contains the substance methylglyoxal (MGO), that is a stable molecule with antibacterial properties that could be proven in vitro (that means in the laboratory, not in the human being) especially against Staphylococcus aureus and E. coli. The MGO concentration as antibacterial agent can be measured in the honey, an investigation from the technical university of Dresden, Germany, revealed that the content of MGO in different honeys varies from 20-800mg/kg honey. At the moment, the honey is used in medicine mainly for the treatment of wounds (not uncontroversially, depending on what kind of wounds, however), as you can bring the active agent MPO with this treatment directly to the place of action.
With bringing MPO to the lungs, it is totally different. If you eat Mankua honey, MGO has first of all to pass the gastric acid without being destroyed, then has to be taken up by the bowel epithelium to be released in the blood, then has to pass the liver without being destroyed and after all this, a final “blood concentration” of MGO will result and this MGO concentration in the blood reaches the lung, but has again to be transported from the lung bloodstream to the inflammatory tissue. I did not find any studies on human beings that investigated the blood concentration of MGO after oral intake of Manuka honey. One would assume, that the amounts that you have to eat of this honey would be very much too high, in order to achieve an antibacterial MGO blood concentration (probably kilograms of honey per day). Furthermore, even if you could get a blood concentration that would be high enough to kill bacteria, one would expect also side effects of this MGO concentration; in the literature, the efficacy and toxicological harmlessness of MGO is discussed controversially.
In summary, large studies at first with animals, then with human beings, would be needed in order to find out about dosages, blood levels and side effects of MGO before one could say anything about its antibacterial property when taken orally in form of Manuka honey.
For antibiotics, all these studies have been done before their usage has been considered to be safe and effective, and indeed, not all antibiotics are suitable for the oral intake. As mentioned above, they are not absorbed from the gut or are destroyed by the liver, therefore, those antibiotics can only reach the blood and then the lung if given directly into the veins.
Be also aware of deception: especially in England, there are many “Manuka honeys” on the market that are not real Manuka honeys, as they do not contain MGO.
Best regards,
Dr. Daniela d’Alquen (Coordinator of the Central English Archive)
01.04.2014