The festive fir in the corner of your living room harbours mould, which can aggravate the lungs.
Leading charity Asthma UK has urged people to be vigilant over the Christmas period.
Their data shows around 300 people are admitted to hospital on Christmas Day each year, suffering severe attacks, that could be linked to the festive favourite.
Mould that naturally grows on your tree can multiply in the warm temperatures of your living room.
And fake trees aren’t the safe alternative they may seem to be, gathering dust and mould in the loft, that can aggravate the lungs.
But, those with allergies as well as asthma sufferers should be alert to the dangers, Asthma UK urged. The moulds are naturally occurring on the trees, but flourish when they are inside our toasty warm homes in the winter.
But the charity also warns that both real and fake trees can also pose a threat.
Fake trees are a great alternative if the allergens that form on a real tree cause you too many breathing difficulties.
But artificial trees, and decorations, can gather dust and mould when they are kept in storage for the year which can cause a flare-up of symptoms when you put it up.
So it’s a good idea to wipe them down when you pull it out of storage and wrap them in plastic to keep the dust at bay when you put them away again.