The Festive Duality of Mistletoe

Each Christmas many households across the globe can be found putting mistletoe in their doorways and many singles at Christmas parties can be found lingering beneath some in the hopes of finding their next significant other. However, this is not the only use of Mistletoe currently. Recently the alternative uses of mistletoe have been analysed and it has been found to be effective in the treatment of cancer.

As a society we are becoming more and more aware of the different dangers that surround us and thus we have become more aware of mistletoe poisoning. The mistletoe berries are known to be the poisonous component of the evergreen plant as they have Phoratoxin and Viscotoxin which are poisonous proteins which, according to lovethegarden.com, may cause:

• Blurred vision

• Fever

• Hallucinations

• Diarrhoea

• Nausea

• Stomach pain

• Vomiting

• Drowsiness

• Slowing of the heart rate

• Heart problems

• Miscarriage in pregnant women

when ingested. However, as you can see, it is very rare for the symptoms to be lethal so therefore all of our worries are unfounded? Although the affects of the berries are seemingly insignificant in the grand scheme of poisons it is still an unpleasant experience which will inevitably be exacerbated in the instance of children and pets.

However, mistletoe berries have been used in cancer treatments in Germany, the berry extracts are used as an adjuvant therapy, which is the stage which follows the primary treatment to reduce the chance of the cancer cells from returning. And is usually administered by injection under the skin or into the tumour itself in some rare cases. Most of the clinical trials on the use of mistletoe berry extract have been conducted in Europe however the efficacy of these trials is unclear as they have not had large enough samples, a lack of patient information, a lack of dose information and the structure of the trials themselves has been disputed. Putting these issues aside they did find:

• In a seven year study (on colorectal cancer) they found that, although there was no declared difference in effectiveness of the mistletoe compared to chemotherapy but the patients treated with mistletoe did experience fewer adverse affects, their symptoms were less extreme and improved disease-free survival.

• In a similar study released in 2013, which focused on advanced pancreatic cancer, showed that the patients who had been given the mistletoe treatment had improved survival and reduced symptoms than those who did not.

There have of course been other studies which have had results to the same effect. In the same way there have been very few serious side effects of this treatment. There have been instances of inflammation and soreness at the site of injection as well as headaches, fevers and chills. There have also been some cases where anaphylactic shock has been induced via an allergic reaction but this is a regular response to an injection and is no surprise and there have been cases of damage to the liver which is easily reversed. On the up side the use of the mistletoe treatment has not caused the immune system to weaken which is significantly better than other treatments.

Mistletoe is fairly easy to find, especially in winter when coniferous trees have lost their leaves and the evergreen mistletoe remains. It can be found on the branches of trees such as hawthorn, poplar, lime and apple trees (which are the most common place they are found in the UK). They can be found in Wales, the West Midlands and the South of England but their range has been expanding due to the rise of continental blackcaps from Germany, which is a type of bird which eat the mistletoe berries and then spread the seed elsewhere.

To conclude it is clear that in certain circumstances mistletoe could be detrimental to the comfort of anyone who makes the mistake of ingesting the berries, but while in use as a decoration in doorways and other high up places the danger of this is seemingly nil. On the more clinical side mistletoe has also been used as an effective adjuvant therapy in the treatment of cancer but the studies on this have not been extensive enough to allow for the treatment to become widely used.

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References:

• "what happens if you eat mistletoe", from lovethegarden.com, accessed 21/12/2020 https://www.lovethegarden.com/uk-en/article/what-happens-if-you-eat-mistletoe

• "where does mistletoe grow?", from the national trust website, accessed 21/12/2020 https://www.woodlandtrust.org.uk/blog/2018/12/where-does-mistletoe-grow/

• "Mistletoe Extracts (PDQ®)–Patient Version", from the National Cancer Institute, accessed 21/12/2020 https://www.cancer.gov/about-cancer/treatment/cam/patient/mistletoe-pdq#:~:text=Most%20clinical%20trials%20using%20mistletoe,effective%2C%20weaknesses%20have%20been%20reported.

• "definition of adjuvant therapy", from the National Cancer Institute, accessed 21/12/2020 https://www.cancer.gov/publications/dictionaries/cancer-terms/def/adjuvant-therapy

• Image via "why do we kiss under the mistletoe", from BBC newsround, accessed 21/12/2020 https://www.bbc.co.uk/newsround/16164453

• "Molecules at an exhibition" by John Emsley, Oxford University Press 1999, page 70