Living with a forest fir tree for a number of weeks could lead to Christmas tree syndrome.
Mould can grow on Christmas trees, which are released as spores into the home.
The spores can cause a number of symptoms, similar to hay fever.
In asthma patients, the spores could lead to lethal asthma attacks, according to charity Asthma UK. Thousands of patients are admitted to hospital every year in December due to asthma attacks, it added.
Asthma UK’s in-house GP, Dr Andy Whittamore, said: “Most of the time mould is obvious in the home, but many people don’t realise that mould also naturally grows on Christmas trees.
“This is made worse when people turn their heating on, as the warmer temperature encourages mould to grow faster.
“Mould can be a real problem for the 5.4 million people with asthma in the UK, causing allergic reactions that can trigger asthma symptoms and, in some cases, life-threatening asthma attacks.”
Asthma patients should take their preventative inhalers, as prescribed, to minimise risk of Christmas tree syndrome, Whittamore added.
A US study in 2011 claimed Christmas trees could harbour up to 53 different types of mould.
Pollen from other trees could also get lodged in the bark of Christmas trees, which are also subsequently brought into the home.
Airborne allergies expert, Max Wiseberg, said: “Decorating the Christmas tree should be a fun time, but for those suffering with Christmas tree syndrome, this can trigger some decidedly un-festive reactions including sneezing, sniffling and general hay fever-like symptoms.
“However, there’s no escape even if you’ve cheated with an artificial one as these can harbour dust which may trigger dust allergy reactions,” said Wiseberg, who is also creator of the HayMax allergen barrier balm.
Plastic, fake Christmas trees could give off toxic fumes, according to Functional Health Coach, Fran McElwaine.
“Plastic on the other hand, gives off toxic fumes, is unsustainably in-destructible and feeds into the false narrative that convenience and cookie-cutter good looks are all that counts.
But, one research claimed natural Christmas trees had beneficial effects on people.
University of Surrey Environmental Psychologist, Dr Birgitta Batersleben said people living near nature have reported higher wellbeing and satisfaction with life.