Choose carefully! How your Christmas tree can reduce stress levels

Christmas brings with it a rich tapestry of aromas—and one in particular has been scientifically proven to boost your health. 

Sadly, it's not the saccharine waft of a freshly unwrapped Celebration (make mine a Bounty, please), it's the smell of pine, the zingy, nasal scent which cuts through the air like a rickety sledge down a snowy slope.

Many plants release compounds called phytoncides which protect them from insects, bacteria, and fungi, which in the case of thyme, rosemary, eucalyptus and mint, are harvested and used to make essential oils. 

Similarly, trees in the conifer family—pine, cedar, fir and cypress—release a phytoncide called alpha-pinene which has been proven to reduce stress levels, and is the foundation of the Japanese wellness practice of Shinrin-Yoku.

Also known as forest bathing, it involves taking time out from the city or an urban area and embracing nature—hugging trees is optional, but encouraged—letting the ambiance of the woodland wash over you as you take in lungfuls of its heady smorgasbord of smells.

In Japan—where the life expectancy is around 85 compared to the UK's 81—spending time walking through the forest is regarded as being part of a healthy lifestyle, and is promoted as way to relax and manage stress. 

And a 2024 study which looked at previous investigations into the effects of phytoncides confirmed it works. 

Researchers found that exposure to phytoncides increases the levels of natural killer (NK) cells in the body, which are a type of white blood cell which act as a first line of defence against viral infections and cancer. 

Furthermore, the plant compounds were found to reduce levels of cortisol, adrenaline and noradrenaline, proving that they have the potential to calm the parasympathetic nervous system—the network of glands and hormones which control our emotions and sense of wellbeing. 

Dr Mohammed Enayat, a GP and founder of London longevity clinic HUM2N told the Daily Mail that opting for a real Christmas tree over an artificial one is 'festive biohacking at its simplest.' 

He explained: 'The scent from a real Christmas tree is rich in natural antimicrobial compounds called phytoncides. 

'These compounds, released by pine, spruce and fir trees as part of their own immune defence, are biologically active, and when we inhale them, they don’t just ignite our senses, they interact directly with our nervous system to offer health and wellness benefits.' 

He added that they can have a similar calming effect on our nervous system as 'meditation or deep breathing'.

'That instant sense of grounding you feel when you walk into a room with a fresh Christmas tree is your biology responding,' he said.

'The aromatic oils released by evergreens travel through the olfactory system, which has a direct line to the limbic brain (the centre responsible for emotion, memory, and the regulation of stress hormones). 

'It’s a powerful reminder that scent is one of the fastest ways to influence mood and physiological state.

'In many ways, this is festive biohacking at its simplest—using a natural sensory cue to reduce mental load, support relaxation and even prime your body for deeper sleep during what is typically an overstimulating, highly stressful season.' 

But the potential benefits aren't just found at home, they can begin from the moment you go out to choose the perfect tree for your home. 

Alex Manos, Functional Medicine Expert at exclusive London longevity clinic The HVN, shared some insights with the the Daily Mail that might make you see your trip to the Christmas tree farm in a new light.  

'One of the things we're starting to understand about forest bathing is that it is innately healing for us,' he said.

'The essential oils emitted by the trees influence Natural Killer cell activity, which in turn boosts our overall immune system. 

'Because it's causing an increase in our NK cells, and the proteins within them, some scientists have argued that forest bathing has a preventative effect on diseases such as cancer.' 

He added that the physical nature of forest bathing also improves cardiovascular health, which in turn can protect against other life-limiting illnesses. 

'What we see in forest bathing are also things like improvement in blood pressure and a reduction in cortisol, our key stress hormone.

'However there is little research to establish if the benefits of forest bathing can be replicated from inhaling the extracted essential oils that trees such as pine produce.'

Another big question which remains to be answered is if a cut tree still release phytoncides, and if they do, how long for once the plant has effectively been killed. 

Manos said: 'Most Christmas trees do not come with their roots, they are not living in a pot, so we're dealing with a dying tree, which is really sad. 

'Obviously you still get the aroma,  and therefore I can only assume you are getting some of the compounds, but they're probably declining quite rapidly.' 

Sadly, not everyone has an easy time during the festive season because 'real' trees have the potential to cause hay fever like symptoms.

Dr Donald Grant, GP and Senior Clinical Advisor at The Independent Pharmacy said that Christmas trees can cause eczema breakouts and allergic reactions, leading to sneezing, coughing, streaming eyes and disrupted sleep.

'The main trigger is through sap and oils found on these trees. Many trees contain rosin, causing contact dermatitis and irritating sensitive skin.

'This phenomenon is labelled ‘Christmas Tree Syndrome’ and consists of dust, pollen and terpenes causing respiratory issues and allergic reactions.

'To minimise its effects, treatments such as Benadryl Allergy Relief can be effective at reducing symptoms and is a popular medication for hay fever in summer.

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'Certain trees can provide a higher allergy risk than others, fir trees are typically less reactive than pine, meaning they could be a better choice for households with skin conditions or respiratory concerns.'

However, even if the sight of a Christmas tree brings you out in hives, there is a hypoallergenic way to benefit from the power of pine. 

Pycnogenol is an extract of the French maritime pine tree (Pinus pinaster) which has long been heralded for its antioxidant and anti-inflammatory properties. 

Pharmacist Deborah Grayson, who posts as The Godmother of Pharmacology on TikTok, says she recommends it to patients 'at least once a day'.

She told the Daily Mail: 'It is one of my favourite supplements as it has many uses and can be helpful for a number of health issues due to its anti-inflammatory action. 

'I have used it for many things for clients and for myself, including lowering eye pressure in glaucoma, menopause, endometriosis, eczema, asthma, hay fever, poor circulation, high blood pressure and metabolic health. 

'There is not a day when I don’t recommend it at least once.

'It does, however, impact blood clotting and should be avoided in patients who are on blood thinning medication.'